M ECHANISMS
OF CONTROLLING
COLOUR AND AESTHETIC
APPEARANCE OF THE
P HOTOGRAPHIC S ALT
PRINT
A thesis submitted in fulfilment of the requirements for
the degree of Master of Applied Science (Photography)
Eleanor (Ellie) D. Young
School of Applied Sciences
Science, Engineering and Technology Portfolio
RMIT University
February 2008
D E C LARAT ION
Th i s
th esi s
con tai n s
no
mat er i al
wh i ch
h as
been
accepte d for th e awar d of an y o th er degr ee or di pl oma
i n an y u n i ver si ty an d, to th e best of my kn o wl edge an d
bel i ef,
con tai n s
no
mater i al
pr evi ou sl y
pu bl i sh ed
or
wr i tten by an oth er per son , ex cep t wh er e du e r efer en ce i s
made i n th e t ex t of th e th e si s. Th i s th esi s con tai n s n o
wor k
th at
was
per for med
p r i or
to
th e
offi ci al
com men cem en t date of th i s r esea r ch pr oject.
Eleanor (Ellie) D. Young
ii
CONTENTS
DECLARATION ..................................................................................... II
LIST
OF
FIGURES ................................................................................. IV
LIST
OF
CHARTS.................................................................................. VI
LIST
OF
TABLES .................................................................................. VI
A C K N O W L E D G E ME N T S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIII
ABSTRACT ......................................................................................... 1
INTRODUCTION ................................................................................... 3
BACKGROUND ..................................................................................... 6
R E S E A R C H D E S I G N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
CH AP T ER 1 T H E FO RM U L AS ................................................................ 15
CH AP T ER 2 T H E P AP ER ....................................................................... 28
CH AP T ER 3 CO AT ING T H E P AP ER ......................................................... 38
CH AP T ER 4 T H E NEG AT I V E .................................................................. 45
CH AP T ER 5 EX P O S ING T H E P RINT ........................................................ 60
CH AP T ER 6 P RO C ES S ING T H E P RINT ..................................................... 71
CH AP T ER 7 D IS CU S S IO N ..................................................................... 84
CH AP T ER 8 CO NCLU S IO N .................................................................... 89
A P P E N D I X 1 S A L T F O R M U L A S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
A P P E N D I X 2 T O N E R F O R M U L A S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
APPE ND IX 3 DEVE LOPER
AND
FIXER
FORMULAS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
G L O S S A R Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
R E F E R E N C E S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
A T T A C H M E N T 1 C D : M I S C E L L A N E A P H O T O G E N IC A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
A T T A C H M E N T 2 T H E S A L T P R I N T M A N U A L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
iii
LIST
OF
FIGURES
Figure 1- 1 Sodium Chloride + silver nitrate ............................................... 17
Figure 1- 2 Ammonium Chloride + silver nitrate ......................................... 17
Figure 1- 3 Sodium Chloride + silver nitrate + sodium citrate. ..................... 17
F i g u r e 1 - 4 A m m o n i u m C h l o r i d e + s i l v e r n i t r a t e +s o d i u m c i t r a t e . . . . . . . . . . . . . . . . 1 7
Figure 1- 5 Sodium Chloride + silver nitrate + Potassium Dichromate ........... 17
Figure
1-6 Ammonium Chloride + silver nitrate + Potassium
Dichromate ................................................................................... 17
Figure 1- 7 Silver chloride % diff eren ces .................................................... 20
Figure 1- 8 0.2% Gelatin Binder ................................................................ 23
F i g u r e 1 - 9 2 % Ge l a t i n B i n d e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3
Figure 1- 10 Arrowroot ............................................................................ 23
Figure 1- 11 Albumen .............................................................................. 23
Figure 1- 12 Binder surfaces ..................................................................... 24
Figure 1- 13 Measles ................................................................................ 26
Figure 1- 14 Silver Nitrate Variances .......................................................... 26
Figure 2- 1 Bergger Paper High Magnifications ............................................ 32
Figure 2- 2 Talbot Paper High Magnif ications ............................................ 33
Figure 2- 3 Arches Platine High Magnifications ........................................... 33
Figure 2- 4 Fab riano Artistico High Magnifications ..................................... 33
Figure 2- 5 Buxton Paper High Magnif ications ............................................. 33
Figure 2- 6 Bergger Paper ......................................................................... 34
Figure 2- 7 Talbot Paper ........................................................................... 34
Figure 2- 8 Arches Platine ......................................................................... 34
iv
Figure 2- 9 Fab riano Artistico ................................................................... 34
Figure 2- 10 Buxton Paper ......................................................................... 34
Figure 3- 1 Glass Rod ................................................................................ 39
Figure 4- 1 A Negative and B Salt Print ....................................................... 49
Figure 4- 2 PMK Tones in Digital Negatives ................................................ 55
Figure 4- 3 Spectral Negatives ................................................................... 57
Figure 5- 1 Cut- off Filter T ests ................................................................. 61
Figure 5- 3 Bronzing Surface Detail ........................................................... 68
Figure 5- 2 Self Masking ........................................................................... 68
Figure 5- 4 Bronzing high Magnification ..................................................... 69
Figure 6- 1
Sod ium Chloride – no Toner ................................................... 75
F i g u r e 6 - 2 S o d i u m C h l o r i d e – Go l d B o r a x T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5
F i g u r e 6 - 3 S o d i u m C h l o r i d e - Go l d T h i o c y a n a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5
Figure 6- 4 Sodium Chloride – Platinum ..................................................... 75
F i g u r e 6 - 5 S o d i u m C h l o r i d e - Go l d B o r a x a n d P l a t i n u m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5
Figure 6- 6 Ammonium Chloride + Gelatin - No Toner ................................. 75
F i g u r e 6 - 7 A m m o n i u m C h l o r i d e + G e l a t i n - Go l d B o r a x T o n e r . . . . . . . . . . . . . . . . . . . . . 7 6
F i g u r e 6 - 8 A m m o n i u m C h l o r i d e + Ge l a t i n
- Gold Thiocyanate ................... 76
Figure 6- 9 Ammonium Chloride + Gelatin - Platinum Toner ........................ 76
Figure
6 - 1 0 A m m o n i u m Ch l o r i d e + Ge l a t i n
- Go l d B o r a x a n d
Platinum ....................................................................................... 76
F i g u r e 6 - 1 1 A m m o n i u m C h l o r i d e + G e l a t i n - Go l d A c e t a t e . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6
Figure 6- 12 Ammonium Chloride + Gelatin
- Palladium Toner ..................... 76
Figure 6- 13 A lbumen No Toner ................................................................. 76
F i g u r e 6 - 1 4 A l b u m e n Go l d B o r a x T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7
Figure 6- 15 A lbumen Platinum Toned ........................................................ 77
Figure 6- 16 A lbumen Palladium Toned ...................................................... 77
F i g u r e 6 - 1 7 A l b u m e n Go l d A c e t a t e T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7
v
F i g u r e 6 - 1 8 A l b u m e n Go l d T h i o c y a n a t e T o n e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7
F i g u r e 6 - 1 9 A l b u m e n Go l d B o r a x a n d P l a t i n u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7
F i g u r e 6 - 2 0 A l b u m e n Go l d T h i o c y a n a t e a n d P l a t i n u m T o n e d . . . . . . . . . . . . . . . . . . . . . . . 7 7
Figure 6- 21 Heat Toned High Magnification ............................................... 79
Figure 6- 22 Heat Toned............................................................................ 80
Figure 6- 23 Result of Heat T on ing ............................................................ 80
LIST
OF
CHARTS
Chart 4-1 Film Density Read ings .............................................................. 51
Chart 4-2 Film Print Comparison ............................................................. 52
Chart 4-3 Film Transmission .................................................................... 58
Chart 5-1 Silver Chloride S ensitivity ......................................................... 62
Chart 5-2 Cut-off Filters .......................................................................... 62
Chart 5-3 Film Transmission .................................................................... 64
Chart 5-4 UV Tube Wavelenghts ................................................................ 66
Chart 6-1 Albumen Toning ....................................................................... 78
Chart 6-2 Sodium Chloride Toning ............................................................ 78
Chart 6-3 Ammonium Chloride and Gelatin ................................................ 78
LIST
OF
TABLES
Table 1-1 Chlorides and Additives ........................................................... 18
Table 1-2 Other chlorides ....................................................................... 21
Table 1-3 Binders ................................................................................... 23
Table 2-1 Pap er Colours .......................................................................... 35
Table 4-1 Film Density Readings ............................................................... 50
Table 5-1 Exposure Tomes ....................................................................... 65
Table 6-1 Heat Toning ............................................................................. 80
vi
vi i
A C K N O W L E D GE M E N T S
Th e au th or wi sh es to th an k th e fol l o wi n g pe opl e wh o gave
en or mo u s con ti n u al su pp or t du r i n g th i s pr oject.
A ssoci ate
Pr ofe ssor
Gal e
S pr i n g :
R M IT
A ppl i ed
S ci en ce
(Ph otogr aph y)
Ph r ed Peter se n : R M IT A ppl i ed S ci en ce (Ph otogr aph y)
A l an E l l i ott : Con su l ti n g ch emi st.
Dr
S tu ar t
Hen der son :
Ul tr aviol et
R adi ati on
S ecti on
of
S ecti on
of
A R PA NS A.
Dr
Joh n
Javor n i cz ky:
Ul tr av i ol et
R adi ati on
A R PA NS A.
D r M i ch ael War e : Con su l ti n g ch emi st
Ph i l l i p Fr an c i s: M an ager , R M IT M i cr oscop y & M i cr oan al ys i s
Faci l i ty
A ppl i ed Ph ysi cs
James R ei l l y : D i r ector , Image Per man en ce In sti tu te R och e ster
In sti tu te of Tech n ol ogy R och e ste r , NY
Pr ofessor M al col m M cC or mack : R M IT Un i ver si ty
Tr i sh an d War r en S i mpson : S i mpson Gr aph i cs
L oth ar Hu ber : B on d Imagi n g , R i chmon d
D an i el l e E dwar ds : A u sti n R epatr i ati on Hospi tal , Hei del ber g
M i ch ael Gr ey : For mer Cu r ator of Ph otog r aph y at th e Fox Tal b ot
M u seu m UK . (Gr ey i n tr odu ced th e sal t pr i n t to th e au th or in
1 9 99 )
vi i i
M ECHANISMS
OF CONTR OL LING COL OUR AND AEST HETIC
P HOTOGR APHIC S ALT
APPEARANCE OF THE
PRINT
ABSTRACT
Th e sal t pr i n t i s an i mp or tan t pa r t of ph oto gr aph y , both i n i t s
h i stor i c val u e an d i n th e t on al r an ge i t can pr ovi de. Th i s ton al
r an ge i s gr eater th an an y oth er ph otogr aph i c pr i n ti n g pr oc ess
avai l abl e to date attr i bu ted to th e i n h er en t mas ki n g abi l i ty of
th e metal l i c si l ver . Ho wever t h e i n tr i n si c pr odu cti on pr obl e ms
h ave
made
it
a
„for gotten ‟
p r ocess.
Th e r e
ar e
fi ve
key
pr obl ems .
1 . Th e
di ffi cu l ti es
in
ach i evi n g
the
poten ti al
ex ten si ve
ton al r an ge .
2 . Th e var yi n g col ou r of th e pr i n t .
3 . S tai n i n g th at appear s i n th e p r i n t, du r i n g an d after
pr ocessi n g.
4 . In stabi l i ty an d l on gevi ty o f th e s al t pr i n t .
5 . Con tr adi ctor y
an d
i n accu r ate
i n for mati on
in
m ater i al
pu bl i sh ed on th e sal t pr i n t.
A l th ou gh t h e emph asi s o f th e r esear ch i s on ex pl or i n g an d
con tr ol l i n g th e col ou r an d ton al r an ge , th e stai n i n g pr obl ems
an d stabi l i ty of th e pr i n t ar e a l so addr essed .
Th e mater i al s u se d for con t act n egati ves to day var y i n b oth
captu r e an d
tr adi ti on al
ou tpu t,
wet
f r om
an al ogu e fi l m
dar kr o om to a
pr oces sed
var i ety of
in
tr an spar en t
th e
fi l m
pr i n ted fr om di gi tal fi l e s . In ade qu ate den si t y an d ton al r an ge
can
affect
ex posu r e
all
ti me
type s
for
of
th e
n egat i ves .
sal t
p r i n ts
To
pr ovi de
ex ten ded
su ffi ci en t
ton al
r an ge
adju stm en ts to th e n egati ve wer e n ecessar y . L on g ex posu r es
ar e n ecessar y to con ver t su ffi ci en t si l ver sal ts to th e i mage
1
maki n g
me tal l i c
si l ver .
Th i s
m ax i mi ses
th e
i n tr i n si c
s el f -
maski n g pr oce ss .
Ul ti matel y th i s r esear ch h as u n c over ed ways t o con tr ol col ou r
an d ton al r an ge an d cer tai n aesth eti c qu al i ti es of th e sal t
pr i n t , wh i l e si mu l tan eou sl y r esol vi n g some of th e con fl i cts i n
pu bl i sh ed i n for mati o n . A ccu r ate an d c on si sten t me th ods of
pr ocessi n g el i mi n ate stai n i n g , pr ovi di n g s ome stabi l i ty to th e
pr i n t . Th e acti vi ti e s an d step s ca r r i ed ou t to make a sal t pr i n t
ar e
man u al ;
pr eci se
du pl i cati on
is
th er efor e
al most
u n attai n abl e. Never th el ess, a l th ou gh test s on a den si t ome ter
may di spl ay n u m er i c di ffer en ces , vi su al di ffer en ces ar e bar el y
n oti ceabl e.
2
INTRODUCTION
Th e sal t pr i n t wa s di sco ver ed i n 1 83 3 by Wi l l i am Hen r y Fox
Tal bot
(1 8 0 7
–
1 87 7 ).
Th i s
two- step
pr oce ss
for m s
l i gh t
sen si ti ve pap er . Fi r st, th e paper i s coated wi th a sal t sol u ti on .
Th en , si l ver n i tr ate sol u ti on sen si ti ses th e pap er by cr eati n g
si l ver ch l or i de. E x posu r e to l i gh t ch an ges th e si l ver ch l or i de
to i mage ma ki n g me tal l i c si l ver . Th i s s ame pr oces s occu r s i n
al bu men pr i n ti n g. A l bu men pr i n ti n g h ad an en or mou s i mpact
for an ex ten si ve per i od of ti me i n th e 1 9 t h cen tu r y. It i s o ften
tr eated as a di ffer en t pr oce ss bu t essen ti al l y i t i s a sal te d
paper pr i n t wi th an al bu m en bi n der . Th i s was th e r ati on al e f or
i n cl u di n g
th e al bu men
pr i n t
in
th i s r esear ch .
A l bu men
is
n or mal l y made fr om th e wh i t e of h en ‟ s eggs.
A l th ou gh
th e
sal t
pr i n t
is
q u i te
si mpl y
t wo
ch e mi cal s
combi n ed on paper to ma ke th e l i gh t sen si ti ve si l ver ch l or i de,
i t i s fr au gh t wi th pr obl em s. Th es e pr obl ems can i n ter fer e wi th
th e appear a n ce an d th e stabi l i ty of th e sal t pr i n t. Wi th few
ex cepti on s mos t pr i n ted tex ts t oday pa y l i ttl e r egar d to th e
compl ex i ti e s of th e pr oc ess an d th e i n tr i n si c pr obl em s. S al t
pr i n ts can pr ovi de a wi d e r an ge of col ou r s an d ton e s. Ho wever
th ese c ol ou r s can be d i ffi cu l t to pr edi ct or c on tr ol . It i s
th er efor e
n ecessar y
to
u n der st an d
h ow
di ffer en t
ch emi cal
sol u ti on s an d var i ou s pr oces ses an d meth ods i n fl u en ce th e
ou tcom e of th e pr i n t. Th e sal t pr i n t h as an ex tr aor di n ar y ton al
r an ge wh i ch i s n ot ach i evabl e i n an y ot h er ph otogr aph i c pr i n t
pr ocess. Th i s t on al r an ge can on ly be gai n ed by n egati ves wi th
speci fi c qu al i ti es th at can u ti l i se th e u n i qu e sel f - mas ki n g
abi l i ty of pr i n ti n g -ou t si l ver ch l or i de.
A IM A ND S COPE
Th e ai m of th i s stu dy i s t o ex p l or e an d de vel op meth od s of
con tr ol l i n g col ou r wh i l e over co mi n g man y of th e i n h er ent
pr obl ems i n th e pr oces si n g. B ec au se to th e en or mou s var i ety
of
paper
avai l abl e,
tes ti n g
for
pr i n ti n g
was
n ar r o we d
to
pr i mar i l y 1 0 0 % cotton paper s.
3
Th e n egati ve was cr i ti cal i n r eal i si n g th e fu l l p oten ti al o f th e
sal t
pr i n ts
ton al
r an ge.
Th e
fi l m
teste d
was
l i mi ted
by
avai l abi l i ty i n th e A u str al i an market. Th e r esear ch i n to var i ou s
fi l ms to cr eate di gi tal ou tpu t n e gati ves pr oved to be co mpl ex
an d ti me con su mi n g. It be came c l ear th at an i n -dep th stu d y i n
th i s ar ea wou l d di st or t th e bal an ce of th i s th esi s. Th er efor e
on l y a sel ecte d n u mber of fi l m ou tpu t type s wer e ex ami n e d.
D i gi tal captu r e wa s n ot i n cl u de d du e to th e c ompl ex ch an gi n g
mar ket pl ace of di gi tal camer as.
For mu l as, addi ti ves an d bi n der s ar e an al ysed i n th e fi r st
ch apter ex ami n i n g h ow th e y affec t th e col ou r , ton al r an ge an d
aesth eti c app ear an ce of th e sal t pr i n t. B oth th e L *a. b. col ou r
syste m an d Pan ton e® col ou r ch arts i den ti fy an d as si st wi th
col ou r compar i s on s.
Th e n eed to u n der stan d p aper c ompo si ti on an d pr odu c ti on i s
h i gh l i gh ted, ex pl ai n i n g wh i ch t ypes to u se an d th e col ou r
di ffer en ces th ey mak e i n sal t pr i n ti n g. D i ffer en t meth ods an d
th e pr obl em s fa ced wh en ap pl yi n g for mu l as to th e pap er s ar e
ex ami n ed.
Compl ex i ti es an d ob stacl es i n fi n di n g su i tabl e n egati v e fi l m
mater i al s ar e di scu sse d, i n cl u di n g th e var i ou s for ms an d h o w
each of th ese affects th e ou tco m e of th e sal t pr i n t. Th e effects
th at u l tr a vi ol et (UV ) an d var i ous wa vel en gth s of vi si bl e l i gh t
h ave
on
th e
pr i n t
ar e
ex ami n ed
i n cl u di n g
th e
effec ts
of
ex posu r e ti me, i n ten si t y, h eat a n d h u mi di ty du r i n g ex posu r e.
A n i n vesti gati on of th e effects of pr ocessi n g of th e pr i n t was
car r i ed
pr acti ces
fol l o wed
ou t.
ar e
by
Th i s
is
wh er e
compar ed,
an
over vi e w,
hi stor i cal
an al y sed
an d
i d e n ti fyi n g
an d
con temp or ar y
acces sed.
pr obl em s
Th i s
an d
is
th ei r
sol u ti on s. Th e eval u ati on s an d dedu cti on s of th e pr evi ou s
ch apter s ar e pu l l ed toge th er fo r a di scu s si on an d th e fi n al
con cl u si on s .
T h e Sa l t P r i n t Ma n ua l copy i s pr o vi ded i n A ttach men t 2 of th i s
th esi s. Th i s i s th e ou tcome of t h i s r esear ch , compr essed an d
4
si mpl i fi ed i n to th e for m of a pr acti cal u ser s gu i de. A bou n d
pu bl i cati on i s sch e du l ed for pr i n ti n g by ffotof fi l m p u b l i sh i n g ,
B r i gh ton , UK after th e assessmen t of th i s paper .
A
CD
pr ovi des
an
i l l u str ati ve
compar i son
of
sal t
pr i n ts
ton al i ty an d c ol ou r var i ati on s i n A ttach men t 1 . Th e ph y si cal
ex h i bi ti on
of
th e
wor k
wa s
o pen ed
on
27th
Feb
2008
at
Ph otoS pace, 3 4 D i gh t S t. Col l i n gwood 3 0 6 6 .
5
B A C K GR O U N D
S i n ce A r i stotl e (3 8 4 -3 22 B C) (E der , 1 9 78 ) th er e i s evi den ce th at
men an d wom en h ave been ex pl o r i n g th e r el ati on sh i p between
l i gh t an d ch emi cal s . It wa s n ot u n ti l 1 8 34 th at Wi l l i am Hen r y
Fox
Tal bot‟ s
i n qu i r i n g
mi n d
l ed
him
to
th e
mom en tou s
di scover y of per man en t ch emi ca l l y pr odu ced i mages cr eated
by l i gh t. Hi s sal ted paper pr i n ts wer e th e fi r st ph ot ogr aph i c
n egati ve -to -po si ti ve
si l ver
pr o cess.
Tal b ot‟ s
„ph otog en i c
dr awi n gs‟ an d h i s con ti n u al di sc over i es h ad a pr ofou n d effect
on both ph otogr aph y an d th e dev el opmen t of pr i n tmaki n g.
Wi l l i am Hen r y Fox Tal bot (1 8 0 0 -1 8 70 ) was an u pp er cl as s wel l
edu cated gen tl e man wi th a br i l li an t mi n d. A s ear l y as 1 84 2
Tal bot pr opo sed th e tel e ph oto l e n s, el ectr on i c fl ash , i n fr ar ed
ph otogr aph y
an d
ph ot oty pe
setti n g,
th u s
setti n g
th e
fou n dati on of ph otogr avu r e. Tal bot pr edi cted th e fu tu r e of
ph otogr aph y
wou l d
f ol l o w
th e
way
of
th e
pr i n ti n g
pr ess
(S ch aaf, 1 9 96 ) . Of Tal bot‟ s for ty - two pu bl i sh ed paper s, th i r ty two deal t wi th l i gh t, de mon s tr ati n g th e ob ses si on h e h ad wi th
th e
po wer
of
l i gh t
(Gr ay
et
al . ,
20 0 2 ) .
Th i s
sch ol ar , ex per i men ter , th i n k er an d ar ti st,
become
on e
n i n eteen th
ph otogr aph i c
of
th e
cen tu r y.
m ost
i n fl u en ti al
For tu n atel y
r esear ch er s
he
ou tstan di n g
was desti n e d to
sci en ti st s
for
docu men ted
of
th e
h i stor i an s
an d
m ost
his
of
ex per i men ts (S ch aaf, 2 0 0 0 ) . Fr om th e wor l d of sci en ce Tal b ot
cr eated a n e w cr aft an d ar t for m. He came i n to ph otogr aph y a s
a „pi ctu r e mak er r ath er th an a sci en ti st‟ (Wal l s an d A ttr i dge,
1 9 77 ) .
Tal bot di sc over ed th e r ati o bet we en sal t an d si l ver n i tr ate
r equ i r ed to cr eate , an d th en „stab i l i z e ‟ an i mage. In 1 8 39 wi th
th e assi stan ce of h i s col l eagu e S i r Wi l l i am Her sch el (1 79 2 –
1 8 71 ), h e was abl e to „fi x ‟ th i s i mage per man en tl y on paper .
D espi te th i s, i mage fadi n g th r ou g h i n adequ ate pr ocessi n g ,
cau se d Tal bo t a gr eat deal of gr i ef.
Th e
ph oto gr ams,
or
as
Tal b o t
cal l ed
th e m
„ph ot ogen i c
dr awi n gs ‟ , wer e cr eated by coati n g wr i ti n g paper wi th a sal t
6
(sodi u m ch l or i de) sol u ti on , to wh i ch after dr yi n g, h e appl i ed a
coati n g of s i l ver n i tr ate sol u ti on . A n object su ch as a l eaf or
l ace wa s pl aced on th e dr y, n ow l i gh t sen si ti ve paper . Tal bot
ex posed th i s to th e su n to cr ea te a n egati ve i mage. Th i s i s
wh at i s cal l ed a sal t pr i n t or sa l ted pap er pr i n t. In 1 8 3 4 h e
began ex posi n g i mage s i n a cam er a. Tal bot pr odu ce d p osi ti ve
i mages by c on tact pr i n ti n g th ese sal t pr i n t n egati ves.
In 1 84 0 h e di scover ed th at Gal l ic aci d d evel op ed ou t a l aten t
i mage on pap er . Th i s cr eated th e fi r st devel ope d -ou t n e gati ve to-p osi ti ve ph o togr aph i c pr i n t pr oce ss an d so dr a mati cal l y
decr eased th e ex p osu r e ti me i n th e camer a fr om h ou r s to
secon d s
(S ch aaf,
2000).
Th e
effect
on
ph otogr aph y‟ s
r epr odu cti ve po wer wa s en or mou s.
S al t
pr i n ti n g i n cl u des
th e
al bumen
pr i n ti n g
pr ocess.
B oth
r equ i r e si l ver ch l or i de as th e fou n dati on to for m an i mage.
Th e Fr en ch ph otogr aph er L ou i s D ési r é B l an qu ar t -E vr ar d ( 1 80 2 1 8 72 ) devel ope d th e al bu men pr i n t i n th e l ate 1 8 4 0 s. He
di scover ed
th e
al bu men
pa per
wh i l e
sear ch i n g
f or
i mpr ovemen t s i n Tal bot‟ s cal o ty pe (pap er n egati ve) pr oces s.
B l an qu ar t -E vr ar d
A cademy
on
pr esen ted
M ay
27,
his
1 8 50 .
By
di scover y
1855
most
to
th e
Fr en ch
ph otogr aph er s
ch an ged to al bu men pr i n ti n g. Th i s r emai n ed th e pr i n ci pal
pr i n ti n g meth od u n ti l 1 8 9 5 . Ex per i men ts on a l bu men wi th ou t
sal t h ad be en car r i ed ou t i n 1 8 3 9 by Tal b ot an d R ober t Hu n t i n
1 8 41 . Th e i mage was n ot mad e fr om si l ver ch l or i de bu t si l ver
al bu mi n ates , wh i ch al so r edu ce s to met al l i c si l ver (R ei l l y,
1 9 80 ) .
„A l ter n ati ve ‟
pr ocess es.
is
a
ter m
u sed
f or
ear l y
ph ot ogr aph i c
pr i n t
S al t pr i n ti n g i s co n si der ed th e fi r st of th e se
pr ocess es . Nu mer ou s pr o ce sse s fol l o wed, su ch as cyan o type,
gu m bi ch r omates, pl ati n u m/ pal l a di u m an d van dyke br o wn .
PHOTOGRAPHIC PRINT P ROCESSES.
Th e maj or categor i es i n wh i ch ph otogr aph i c pr i n t pr oce sse s
fal l ar e „devel ope d -ou t‟ an d „pr i n ted -ou t‟ .
7
D evel oped -ou t, al so kn o wn a s p r ocesse d -ou t, r efer s t o m ost
ph otogr aph i c pap er s wh er e th e i mage i s ca ptu r ed bu t can n ot
be seen u n ti l ch emi cal bath s „de vel op‟ or „ pr o cess‟ th e l at en t
i mage. D escr i bed as th e ch emi c al r edu cti on of si l ver par ti cl es ,
i t i s car r i ed ou t i n th e dar kr o om u n der a r ed sa fe l i gh t .
Pr ocessi n g - ou t h as been th e most com mon pr acti ce of pr i n ti n g
fr om 1 9 0 5 (R ei l l y, 1 9 80 ) u n ti l r ecen tl y wh en di gi tal ou tpu t
su r passed tr adi ti on al wet pr oces s es.
Pr i n ti n g -ou t r efer s to th e pr oce s s es wh er e pr i n ts ar e cr eate d
by l i gh t en er gy on l y. Th e r e ar e n o ch e mi cal ai d s u se d t o
pr odu ce th e i mage. 1 9 t h cen tu r y ph otogr aph i c pr i n t pr oces ses
wer e car r i ed ou t by a pr ocedu r e kn o wn as con tac t pr i n ti n g.
Th e n egati ve i s th e same si z e as th e fi n a l pri n t an d the
n egati ve i s i n „ c on tact ‟ wi th t h e l i gh t sen si ti z ed paper . A
posi ti ve i mag e i s cr eated wh en e x posed to th e u l tr avi ol et an d
vi si bl e l i gh t spectr u m. Th e pr i n t can be vi e wed du r i n g th e
ex posu r e. A h i n ged back pr i n tin g fr ame al l ows ac cess t o ch eck
th e ex p osu r e du r i n g pr i n ti n g. For th e fi r st si x t y -fi ve year s of
ph otogr aph y th i s was th e meth od of cr eati n g ph otogr aph i c
pr i n ts (R ei l l y, 1 98 0 ) .
PRINT TONE
A sal t pr i n t i s mon och r omati c; h owever fr om th e ver y ear l y
yea r s of ph otogr aph y th e var yi n g ton al di ffer en ces h ave been
di scu ss ed . In th e i n tr odu cti on t o T h e P en c i l of Na tur e , 1 844
Tal bot d efen ds th e di ffer i n g col o u r s by s tat i n g “ th er e i s s ome
var i ety i n th e ti n ts th ey pr esen t” an d ar gu es th at th e i mages
su i t th e col ou r s. (S ch aaf, 2 0 0 0 ) S ch aaf su ggest s th at T al bot
may h ave been r el u ctan t t o u se „ fi x er ‟ du e to th e „u n pl easi n g‟
col ou r i t cr eated. Th er e i s di sc u ssi on abou t th e con tr ol of
col ou r bu t i n man y case s th e r ea son s f or th e col ou r var i ati on s
ar e n ot ex pl i cated .
Th e con tr ol of col ou r an d aest h eti c appear an ce of th e sal t
pr i n t r equ i r e d an i n -depth ex pl or ati on of th e ch emi cal an d
mech an i cal
pr oces s es car r i ed o u t
in
pr odu cti on .
Th e h i gh
pr opor ti on of con fl i cti n g i n for m ati on fou n d on pr o cess es an d
8
th e for mu l as i n h i stor i c an d con tempor ar y pu bl i cati on s i s of
con cer n . R ecom men dati on s on fi x i n g th e sa l t pr i n t wer e a case
i n poi n t. Th ey r an ge d fr om 1 0 mi n u tes i n a 1 0 % sodi u m
th i osu l ph ate bath (Cr a wfor d, 1 9 7 9 ) to th e oth er ex tr eme of
two bath s wi th
3 0 secon ds i n e ach bath of 1 0 % sodi u m
th i osu l ph ate (Ja mes, 2 0 0 2 ) . A l thou gh th ese ar e th e ex tr eme s,
n ot on e of th e fol l o wi n g pu bl i ca ti on s con cu r : (B ar n i er , 2 00 0,
Far ber , 1 9 98 , R ei l l y, 1 98 0 , Webb an d R ee d, 2 0 0 0 ) . S i mi l ar
i n stan ces
th r ou gh ou t
th e
meth ods
an d
f or mu l a s
in
th es e
pu bl i cati on s en cou r age i n vesti gat i on .
S can n i n g
E l ectr on
destr u cti ve
M i cr oscope s
me th od
to
h ave
an al yse
been
h eavy
i n vesti gat i n g th e stabi l i ty of or i gi n al 1 9
(War e,
2003).
Th e
si l ver
par ti cl es
u sed
th
si z e s
as
a
metal s
n on wh en
cen tu r y sal t pr i n ts
ar e
di scu s sed
in
r el ati on sh i p to th e fr agi l e n atu r e of th e pr i n t . Th i s si l ver i s
vu l n er abl e to i mpu r i ti es , both at mosph er i c an d i n tr i n si c tr ace
el emen ts . War e an d Jen kyn - Jon es ar gu e t h e col ou r of th e sal t
pr i n t var i es as a r el ati on sh i p to th e per cen tage of su l ph i de ,
affect i n g l on g -ter m stabi l i ty ( Wa r e, 2 00 3 Jen kyn -Jon e s, 1 9 8 8)
Th ey di scu ss th e col ou r i n h i stor i c pr i n ts bu t do n ot r efer to
con temp or ar y sal t pr i n ts .
T h e Al b u men a n d Sa l ted P a p er Book : T h e H i stor y a n d P ra c tic e
of P h otogr a p h ic Pr i n ti n g, 18 4 0 -18 9 5 (R ei l l y, 19 80 ) i s th e most
compr eh en si ve
pr i n ted
mat er i al
avai l abl e
on
th e
sal t
an d
al bu men pr oce ss e s. R ei l l y de scr i bes th e h ea t ton i n g pr oces ses
an d th e col ou r di ffer en ces bet we en fal se u l tr avi ol et l i gh t an d
n atu r al
su n l i gh t
ex posu r es
bu t
fai l ed
to
ex pl ai n
the
ph en omen a occu r r i n g wi th th e si l ver par ti cl es an d ch emi cal s ,
on an d i n th e paper .
A l th ou gh th e di scover y of th e sal t pr i n t i s ackn owl e dged as
th e bi r th of ph otogr aph i c r epr od u cti on , toda y i t h a s l i ttl e r eal
r el evan ce
in
th e
mai n str eam
an d
comm er ci al
wo r l d
of
ph otogr aph y. In fact i t i s on e o f th e l east kn o wn an d pr acti sed
of
th e
„al ter n ati ve
pr oce sses‟ .
S tr on g
ar gu men ts
for
th i s
r esear ch der i ve fr om th e si gn i f i can t h i stor i c val u e an d i t s
9
con si der abl e t on al r an ge wh i ch i s sti l l con si der ed gr eater th an
th a t of al l oth er ph otogr aph i c pr i n ti n g pr ocesses t o date.
10
RESEARCH DESIGN
Ways of c on tr ol l i n g col ou r an d th e aesth eti c ap pear an ce of th e
sal t
pr i n t
wer e
par a mou n t
to
th i s
r esear ch .
R es ol vi n g
i n con si sten ci e s i n cu r r en t an d h istor i cal pu bl i cati on s wa s al so
an i mpor tan t c omp on en t. B ackgr ou n d r esear ch pr ovi ded l i ttl e
i n for mati on
sti mu l ates
on
th e
ac ti vi ty
ch emi cal
wi th i n
reacti on s
th e
pr i n t
or
to
wh at
ph y si cal l y
affect
col ou r .
E x cepti on s wer e fou n d i n ( Jen kyn -Jon e s 1 9 8 8; R ei ll y 19 8 0 ) an d
(War e 1 9 9 4 ). Th ey each di scu s s t h e si l ver par ti cl e si z e an d i ts
r el ati on sh i p to l i gh t wh i ch may affect th e pr i n t col ou r . Th ese
aspect s wer e al so ex pl or ed.
Th e meth od of cr eati n g a sal t pr i n t h as di sti n ct steps. E ach of
th ese step s ar e al l ocated sep ar ate ch apter s. Th i s i sol at e s th e
var i ou s pr obl ems wi th i n each of th e steps . Th e r esu l ts of th e
r esear ch on each of th ese steps a r e dr awn togeth er i n th e fi n al
di scu ssi on to for m th e fi n al con c l u si on .
Th e qu esti on s th i s r esear ch wa s desi gn ed to an s wer ar e as
fol l o ws:
1 . Wh at ar e th e con tr i bu ti n g factor s th at cau se th e col ou r
di ffer en ces i n th e sal t pr i n t?
2 . Can th e col ou r an d vi su al aspects of th e sal t pr i n t
be
pr edi cted an d con tr ol l ed ?
3 . Can col ou r s u sed i n th e spec tr al n egati ve offer th e same
con tr ol i n con tr ast, col ou r an d to n al r an ges as tr adi ti on al
an al ogu e fi l m?
4 . D o con temp or ar y meth od s of pr o cessi n g offer pr ote cti on for
l on gevi ty of th e sal t pr i n t?
11
Th e i n vesti gati on wi l l i n cl u de:
1 . Iden ti fy i n g th e r el ati on sh i p bet ween th e col ou r of th e pr i n t
an d for mu l as, bi n der s an d paper s .
2 . A n a ttempt to d et er mi n e th e r el ati on sh i p bet ween col ou r
an d th e si z e of th e si l ver par ti cl es.
3 . R efi n i n g for mu l as an d meth ods.
PROJECT METHODOLOGY
S al t pr i n t tests wer e pr odu ced i n a con tr ol l ed en vi r on men t
u si n g var i ou s for mu l as , paper s, n egati ve typ e s an d meth o ds.
METHODS
1 . R esear ch
pr i n ted
mater i al
for
both
con temp or ar y
an d
h i stor i c sal t pr i n t for mu l a s, r evi ew an d te st di ffer en ce s.
2 . Test di ffer en t sol u ti on r ati o s o f sal t to si l ver u si n g s tep
we dges t o eval u ate col ou r an d to n al di ffer en ces .
3 . Fi n d
a
r el i abl e
meth od
of
coa ti n g
paper
th at
pr ovi des
con si sten c y an d accu r acy i n appl yi n g sol u ti on s .
4 . R ecor d th e pr i n t col ou r wi th Pan ton e® an d L *a . b. col ou r
syste ms f or con si sten t r efer en ce poi n t s.
5 . E x pl or e d i ffer en t water -s ol u bl e ch l or i des for ch an ge s i n
col ou r , n oti n g possi bl e effe cts on th e l on gevi ty of th e pr i n t.
6 . E x ami n e h o w di ffer en t pa per s aff ect th e ton al r an ge, c ol ou r
an d l on gevi ty.
12
7 . E stabl i sh
a
con tr ol
n egati ve.
Comp ar e
var i ou s
n egati ve
type s, i n cl u di n g spectr al n egati ves to fi n d wh i ch pr ovi des
th e g r eatest ton al r an ge.
8 . E val u ate
th e r espon se of si l ve r
ch l or i de
i n th e var i ou s
spectr u m s of UV tu bes an d su n l i gh t s an d effect on col ou r
an d con tr ast.
9 . Fi n d th e peak sen si ti vi ty of si l ver ch l or i de i n both u l tr a
vi ol et an d vi si bl e l i gh t spectr u m s .
1 0 . In vesti gate ton i n g; co mpar e ch em i cal an d h eat meth od s of
ton i n g . A n al yse col ou r , possi bl e ch an ges i n th e paper an d
si l ver par ti cl es.
1 1 . R evi ew meth od s of pr oce ssi n g pr i n t s an d th e effect s on
th e l on gevi ty an d col ou r .
FE I Nova Nan oS E M was u sed to i n vesti gate an d r esol ve man y of
th e r esear ch qu esti on s . Th i s en v i r on men tal scan n i n g el ectr on
mi cr osco pe i s h ou sed i n th e Ph ysi cs de par tmen t at R M IT. It
pr ovi d ed a ph y si cal vi e w of th e s i l ver par ti cl es. A n E DA X X -r ay
detector attach e d to th e Nan o S E M r eveal ed tr ace el emen ts
pr esen t i n th e sal t pr in t paper , ho wever th er e wer e di ffi cu l ti es
du e to th e paper co mpo si ti on of t h e test sam pl e s.
Th e dete ctor for (E D X) an al y si s d i d n ot ca ptu r e u sabl e i mages;
bu t by empl oyi n g th e TL D an d E D X detec tor s both i magi n g an d
data cou l d be gat h er ed. Hi gh el ectr on en er gy mean t a pr obabl e
cr ystal
cou l d
magn i fi cati on ,
be
on ce
i den ti fi ed
at
focu se d
was
it
abou t
1 3 0 , 0 00
magn i fyi n g
up
ti mes
to
th e
max i mu m of 3 0 0 , 00 0 ti mes wh er e th e cr ystal fi l l ed th e l en s. It
wa s at th i s poi n t th at th e E D X r eadi n gs wer e taken as fe w
oth er el emen ts cou l d di stor t th e r eadi n g.
13
Th e atomi c wei gh t p er cen tage wa s gath er ed f or si l ver an d
su l ph u r i n al l sampl es. A n y u n u su al l y l ar ge peaks i n th e E D X
r eadi n gs
cr eated
by
tr ace
el e men ts
wer e
i n ves ti gated
for
possi bl e r el evan ce.
D r Joh n Javor n i cz ky of th e Ul t r avi ol et R adi ati on S ecti on of
A R PA NS A u sed a CA R Y 5 0 spectr o ph otom eter to assi st wi th th e
gath er i n g of spectr al tr an smi ssi on data of fi l m r equ i r ed for
th i s r esear ch . Th i s i n cl u ded th e spectr al emi s si on r eadi n gs
fr om th e u l tr avi ol et fl or escen t tu bes.
14
Chapter 1 THE FORMULAS
Tests wer e car r i ed ou t on a n u mber of di ffer en t combi n ati on s
of for mu l as to stu dy th e effec t on th e col ou r , th e ton al r an ge
an d th e aesth eti c appear an ce
of th e sal t pr i n t . E ar l y an d
cu r r en t for mu l as wer e ev al u ate d wi th th e best ou tc ome of
each di scu ss ed.
Tal bot u se d s odi u m ch l or i de i n h i s fi r st sal te d pa per pr i n ts.
S odi u m ch l or i de i s co mm on tabl e sal t . T oday mo st tabl e sal t s
con tai n addi ti ve s, (s odi u m al u m i n osi l i cate ) an ti -ca ki n g agen t
to st op m oi stu r e abs or p ti on
a n d may be
i odi z ed ( sodi u m
i odi de). Tes t s fou n d th ese addi ti ves r eact ed wi th th e si l ver
n i tr ate cr eati n g a ch emi cal fog . Th i s r edu c ed th e pr i n t qu al i ty
by degr adi n g th e wh i te i n th e h i gh l i gh t ar eas . A s a r esu l t al l
ch l or i des wer e pu r ch ased th r ou gh
ch e mi cal
su ppl i er s.
Th e
col ou r s of step wedge s pr i n ted on th i s paper wi l l n ot pr ovi de
an accu r ate r epr esen tati on bu t wi l l cl ear l y i n di cate r el evan t
di ffer en ces. A col ou r an al y si s pr ovi ded wi th both Pan t on e®
an d L *a. b. c ol ou r s f or sh ado w an d mi d -ton e s (i n di cat ed b y th e
wh i te poi n ter s) wi l l al l o w th e r ea der to ch e ck th e col ou r s on a
compu ter
scr een
or
c on su l t
a
Pan ton e®
col ou r
ch ar t
if
accu r acy i s desi r ed. A l l F or mu l as ar e set ou t i n A ppen di x 1 .
Th e
fol l o wi n g
i n for m ati on
su m mar i ses
th e
r esu l ts
of
th e
test ed sol u ti on s. Th e fi r st t wo s ol u ti on s wer e th e base f or th e
addi ti ves of sodi u m ci tr ate an d p otassi u m di ch r omate.
o
S ol u ti on s: S odi u m Ch l or i de 2 % , si l ver n i tr ate 12 %
(NaCl
2% + AgNO3 12%)
o
S ol u ti on s: A mmon i u m Ch l or i de 2 % , si l ver n i tr ate 12 %
(NH4Cl 2% +AgNO3 12%)
Wh en com par i n g th e pr evi ou s s ol u ti on s a m mon i u m ch l or i de
wi l l sl i gh tl y decr ea se ex p osu r e ti me an d th er ef or e th e c on tr ast
of th e pr i n t. S odi u m ch l or i de i s sl i gh tl y war m er i n col ou r as
seen i n Fi gu r es 1 -1 an d 1 -2 .
15
SODIUM CITRATE
S odi u m ci tr ate i n cr eases th e r ed u cti on of th e si l ver ch l or i de
an d si l ver ci tr ate to me tal l i c si l v er on ex posu r e to l i gh t. Th i s
decr eases ex p osu r e ti me an d th e r efor e decr eases th e con tr as t.
Con tr ar y to t ex t su gge sti n g s odi u m ci tr ate war ms th e col ou r
r esu l ts of test s f ou n d th at i t c oo l s th e col ou r sl i gh tl y . Th e
ton al r an ge i s ex ten ded gi vi n g mor e br i l l i an ce by se par ati n g
th e ton es . In cr easi n g th e sodi u m ci tr ate per cen tage co ol e d th e
col ou r s
fu r th er .
Fi gu r es
1 -3
an d
1 -4
sh o w
th e
di ffer en ce
bet ween s odi u m ch l or i de wi th s odi u m ci tr ate an d A mmon i u m
ch l or i de wi th s odi u m ci tr ate.
o
S ol u ti on s: S odi u m Ch l or i de 2 % + si l ver ni tr ate 12 % +
sodi u m ci tr ate . 2 % (NaCl 2% + AgNO3 12%+ Na3C6H5O7 2%)
o
S ol u ti on : A mmon i u m Ch l or i de 2 % + si l ver n i tr ate 1 2 % +
sodi u m ci tr ate . 2 % (NH4Cl 2% +AgNO3 12% +Na3C6H5O7 2%)
POTASSIUM DICHROMATE
2 dr ops of potassi u m di ch r oma te ( 5 % sol u ti on ) in 30 ml of the
sal t sol u ti on : (R ei l l y, 1 9 80 )
o
In cr ease d th e con tr ast of th e i ma ge . Fi gu r e s 1 -5 an d1 -6
i l l u str ate s th e ton e l oss i n th e h i gh l i gh ts .
o
In cr ease d th e ex posu r e ti me an d sl i gh tl y war med th e
ton es.
Wh en 2 dr ops of a 1 0 % potas si u m di ch r omat e s ol u ti on wer e
u sed th er e was l os s of i n for mati on i n th e sh ado ws b efor e th e
ex posu r e cou l d r en der de tai l s i n th e h i gh l i gh ts. A n ammon i u m
ch l or i de sol u ti on wi th pota ssi u m di ch r omate i s 8 % to 1 0%
cool er
in
col ou r
th an
sodi u m
ch l or i de
wi th
p otas si u m
di ch r omate . (Th ese col ou r di ffer en ces wer e cal cu l ated fr o m
den si to meter
r eadi n gs)
Th i s
is
i l l u str ated
Fi gu r e
1 -5
an d
Fi gu r e 1 -6 .
V ar yi n g th e amou n t of pot assi u m di ch r oma te al l o wed c on tr ol
over th e con tr ast . Potas si u m di ch r omate i s on l y l i gh t -sen si ti ve
wh en i t h as s ometh i n g to ox i di se l i ke gel ati n .
16
D r War e offer ed th e fol l owi n g ex pl an ati on of h o w di ch r oma te
possi bl y affect s c on tr ast by em ai l on th e 2 9 t h of N ovem ber
2 0 07 .
Potassi u m
di ch r omate
wi th
si l ver
n i tr ate
for m s
i n sol u bl e si l ver ch r omate , th e C r (V I) can n ot ox i di se A g+ an y
fu r th er . Cr (V I) can h owever , ox i di se si l ver metal , A g, to A g+ . It
cu ts
off
th e
h i gh er
val u es
in
th e
ton al
sen si ti vi ty an d i n cr eas i n g th e c o n tr ast.
s cal e ,
r edu ci n g
Th e ch r omi u m(V I) a s
di ch r omate i s „u sed u p‟ wh en th e pr i n t i s made by ox i di si n g
th e si l ver metal , an d i s i n er t wh e n r edu ced to ch r omi u m(III).
o
S ol u ti on s: S odi u m Ch l or i de 2 % + si l ver ni tr ate 12 % +
Potassi u m D i ch r om at e: 2 dr op s of 5 % s ol u ti on i n 3 0 ml s
of sal t sol u ti on . ( NaCl 2 % + AgNO3 12 % + K2Cr2O7)
o
S ol u ti on s: A mmon i u m Ch l or i de 2 % + si l ver n i tr ate 1 2 %
+ Potassi u m D i ch r omate : 2 dr o ps of 5 % sol u ti on i n 3 0 ml s
of sal t sol u ti on . ( NH4Cl 2 % + AgNO3 12 %+ K2Cr2O7)
Figure 1-1 Sodium Chloride + silver nitrate
Figure 1-2 Ammonium Chloride + silver nitrate
Figure 1-3 Sodium Chloride + silver nitrate + sodium citrate.
Figure 1-4 Ammonium Chloride + silver nitrate +sodium citrate
Figure 1-5 Sodium Chloride + silver nitrate + Potassium Dichromate
Figure 1-6 Ammonium Chloride + silver nitrate + Potassium Dichromate
17
S o di um Chl o r i de + si l ve r
ni tr ate
P anto ne ®
S o l i d M att
L*
a.
b.
S h ado ws
4 6 25
20
16
18
M i d-ton es
4 7 05
40
19
17
Ammo ni um Chl o r i de + si l v e r ni tr ate
S h ado ws
B l ack m
12
1
0
M i d-ton es
7 5 30
50
5
12
S o di um Chl o r i de 2 % + si l v er ni tr ate 12 % + so di um c i tr ate
S h ado ws
B l ack m
12
1
0
M i d-ton es
7 5 19
36
6
10
Ammo ni um Chl o r i de + si l v e r ni tr ate + so di um c i tr ate
S h a do ws
B l ack m
12
1
0
M i d-ton es
7 5 31
38
6
13
S o di um Chl o r i de + si l ve r ni tr ate + Po tassi um Di c hr o mate
S h ado ws
B l ack m
12
1
0
M i d-ton es
7 5 04
52
9
19
Ammo ni um Chl o r i de + si l v e r ni tr ate + P o tassi um Di c hr o mate
S h ado ws
B l ack m
12
1
0
M i d-ton es
800
54
10
11
Table 1-1 Chlorides and Additives
VARIATION TO SALT FORMULAS
S al t pr i n ts pr oved to be at th e ir best wh en th e ch l or i de (sal t)
con ten t i s appr ox i matel y 2 % an d th e si l ver sol u ti on i s 1 2 %.
Ch an gi n g th e r at i o of sal t to si l v er can be u sed to con tr ol th e
18
appear an ce an d th e col ou r of th e fi n al pr i n t. Th e sodi u m
ch l or i de sol u ti on was th e bas e fo r mu l a for th e fol l owi n g tes ts.
D E C R E A S E S A L T P E R C E N T A G E : Tal b ot di scover ed th at by de cr easi n g
th e sal t th er e wa s an i n cr eas e i n l i gh t sen si ti vi t y , (S ch aaf,
2 0 00 ) bu t decr easi n g th e ch l or i de sol u ti on bel o w 1 %
pr odu ce pr i n ts th at l ack br i l l i an ce an d den si t y.
ten ds t o
D ecr easi n g
th e sal t i n th e sol u ti on to:
o
0 . 2 % cau se d an i n cr ease i n con tr ast al l o wi n g
i n for mati on i n th e sh ado ws bu t l i ttl e i n th e h i gh l i gh ts
o
0 . 5 % cau se d a fu r th er i n cr ease i n con tr ast . It beca me
war m er i n col ou r an d l os t some d etai l i n th e h i gh l i gh ts .
o
1 % cau se d th e sal t sol u ti on to i n cr ease th e con tr ast an d
th e ton es bec a me war mer i n col o u r .
I N C R E A S E S A L T P E R C E N T A G E : Tal bot fou n d th at by i n cr easi n g th e
amou n t of sal t i n th e s ol u ti on t h e paper be came l ess l i gh t
sen si ti ve (th i s wa s h i s fi r st at tempt at stabi l i z i n g (fi x i n g)
i mages) (S ch aaf, 2 0 00 ) . E ffects of i n cr easi n g th e sal t i n th e
sol u ti on :
o
3 % cr eate d a sl i gh t decr ease i n con tr ast an d th e ton e s
wer e cool er . Th i s per cen tag e p r ovi ded an ac ceptabl e
ton al r an ge, al l owi n g con tr ol ove r con tr ast.
o
5%
cr eated
a
decr ease
in
con tr ast
an d
th e
i mage
appear ed fl at.
o
10%
cr eate d
a
su bstan ti al
de cr ease
in
th e
con tr ast ,
r esu l ti n g i n a fl at we ak pr i n t th at r etai n ed a pu r pl e pi n k
col ou r .
Th e step we dges i n Fi gu r e 1 -7 i n di cate th e effect di ffer en t
per cen tages of s odi u m ch l or i de h ave on th e ton al r an ge an d
col ou r s. Th ey r an ge fr om 0 . 2 % to 1 0 % of sodi u m ch l or i de
con secu ti vel y . A l l wer e ex pose d u si n g a 1 2 % si l ver n i tr ate
sol u ti on .
19
Figure 1-7 Silver chloride % differences
OTHER CHLORIDES
A l an E l l i ott su ggested by emai l 1 0 t h A pr i l 2 00 6 th at m an y o th er
ch l or i de sal ts ar e al s o sol u bl e i n wat er an d th er efor e mayb e
wor th testi n g. Cal ci u m c h l or i de an d pota ssi u m ch l or i de wer e
ch osen
for
tes ti n g
du e
to
ava i l abi l i ty
an d
l o w h az ar d
in
h an dl i n g . B oth test sol u ti on s u se d 2 % r ati o to di sti l l ed water .
Th e col ou r an d ton al r an ge di ffer en ce bet ween each wa s sl i gh t
th er efor e fu r th er testi n g was n ot con si der ed n ece ssar y. Th e
fol l o wi n g Tabl e 1 -2 ou tl i n es th e per for man ce.
In order of warmth of colour
In order of light sensitivity
1 . A mmon i a ch l or i de
1 . Potassi u m ch l or i de
2 . S odi u m ch l or i de
2 . A mmon i a ch l or i de
20
3 . Potassi u m ch l or i de
3 . S odi u m ch l or i de
4 . Cal ci u m ch l or i de
4 . Cal ci u m ch l or i de
Table 1-2 Other chlorides
BINDERS
B i n der s ar e th e su bstan ce s th at bi n d togeth er t wo or mor e
mater i al s or ch emi cal s i n a sol u ti on .
GELATIN BINDER
Th e gel ati n e bi n der su sp en ds th e ch l or i de sol u ti on al s o acti n g
as a si z i n g agen t . Th i s pr even ts th e si l ver par ti cl e s fr o m
si n ki n g i n to th e pa per fi br es; t h e i mage h as mor e acu tan c e
an d appear s br i gh ter .
0 . 2 % of gel ati n cau sed th e pr i n t to become co ol er i n col ou r . A s
th e per cen tage of gel ati n i n cr ea se d th e pr i n t bec a me war mer
an d a sl i gh t sh een app ear ed. 2 % of gel ati n cr eat ed a di sti n ct
su bstr ate el evati n g th e si l ver u p fr om th e paper . Th i s was
evi den t by th e i m pr oved vi si bl e sh ar pn ess of th e i mage an d
vi su al i mages fr om th e FE I No va Nan oS E M . L i gh t beg an to
r efr act i n th i s tr an sl u cen t ar ea a n d as wi th al bu men th e ton e s
became war mer . Gel a ti n bi n der s can b e com par ed i n F i gu r es 1 8 an d Fi gu r es 1 -9 for th e col ou r di ffer en ces.
ARROWROOT BINDER
A ccor di n g to wr i tten tex t (R ei l l y, 1 9 8 0 ) ar r owr oot star ch es
acts a s a si z i n g an d cr eate a war m er ton e wh i l e en h an ci n g
detai l i n th e sh ado w r egi on . R ei l l y ( R ei l l y, 1 9 8 0 ) su ggests th at
th e si l ver n i tr ate sol u ti on r equ ir es ci tr i c aci d. A s “ star ch i s
n ot
an
acti ve
or gan i c
su bstan ce…i t
h as
no
eff ect
on
th e
r edu cti on of si l ver ch l or i de” ( R ei l l y, 1 9 80 p2 2 ). However t e sts
wi th ar r o wr oo t wi th ou t ci tr i c aci d i n th e si l ver n i tr ate sol u ti on
pr oved th i s was n o t n eces sar y .
A r r owr oot wa s di ffi cu l t t o coa t bu t r esear ch u n cover ed an
ear l y for mu l a or i gi n al l y pu bl i sh ed i n 1 9 2 4 (Wal l an d Jor dan ,
21
1 9 75 ) .
Th e
per cen tag e
of
wat er
wa s
h i gh er
an d
so di u m
car bon ate i s i n cl u de d to ma ke i t l ess a c i di c. Th e odou r o f
ammon i a (fr o m a mm on i u m ch l or i de see ar r owr o ot f or mu l a on
page 9 3 ) was pu n gen t wh i l e m aki n g th e s ol u ti on , bu t th i s
r edu ced
in
a
fe w
h ou r s .
Th i s
a m mon i a
a ccel er ates
the
sen si ti vi ty of th e star ch sol u ti on . S tar ch sol u ti on s appear ed to
si t i n th e space bet ween th e pape r fi br es . A s th e pa per dr i ed i t
became ma tt i n appear an ce. It th er efor e h as n ot th e same
l u mi n osi ty as al bu men or gel ati n .
ALBUMEN BINDER
Th e i mage si ts on th e su r face of th e paper pr ovi di n g th e
appear an ce of a gr eater den si t y r an ge th r ou gh th e r efr acti on
of th e l i gh t . It appear ed to r eso l ve fi n e detai l mor e th an th e
pl ai n sal ted pr i n t. D epen di n g on th e coati n g/ s ap pl i ed a n
al bu men pr i n t h as a sl i gh t sh ee n to gl oss y fi n i sh ed su r face,
pr ovi di n g br i l l i an ce , absen t i n sal ted paper pr i n ts.
B eati n g th e egg wh i te br eaks do wn th e al bu men i n to a u n i for m
con si sten c y . Th e sal t an d th e a ci d h el p wi th th e fer men ti n g of
th e al bu men s ol u ti on (se e al bu men for mu l a page 9 2 ) . Th e
sh or ter fer men tati on ti mes cr ea te d a du l l su r face. A fter t wo
we eks
fi n i sh .
of
fer men ta ti on
Th e
su r face
th e
su r face
a ppear ed
du l l
offer ed
wh en
a
th e
better
sol u ti on
gl oss
was
appl i ed u n der 1 5 ° C.
E i th er sodi u m an d a mmon i u m ch l or i de can be u sed i n th e
al bu men sol u ti on to cr eate si l ver ch l or i de , ammon i u m ch l or i de
cr eate s a col ou r 8 % to 1 0 % cool er th an sodi u m ch l or i de. (Th ese
col ou r di ffer en ces wer e cal cu l ate d fr om den si to meter
r eadi n gs)
Th e Fi gu r es 1 -8 to 1 -1 1 an d T abl e 1 -3 i n di cate th e di ffer ent
su r fac es, col ou r s an d ton e s fr om each of th e bi n der s.
22
Figure 1-8 0.2% Gelatin Binder
Figure 1-9 2% Gelatin Binder
Figure 1-10 Arrowroot
Figure 1-11 Albumen
0.2% Ge l ati n Bi nde r
P anto ne ®
S o l i d M att
L*
a.
b.
S h ado ws
B l ack M
12
1
0
M i d-ton es
7 5 18
40
19
17
S h ado ws
7 9 75
19
17
8
M i d-ton es
7 5 17
52
16
15
S h ado ws
B l ack m
12
1
0
M i d-ton es
4 7 05
40
19
17
S h ado ws
4 9 75
19
17
8
M i d-ton es
876
49
17
26
2% gel ati n B i n der
Arrowroot
Al bume n
Table 1-3 Binders
Comp ar i son i n Fi gu r e 1 -1 2 sh ows th e di ffer en t su r faces at
h i gh
magn i fi cati on .
A l th ou gh
th e
magn i fi cati on s
ar e
n ot
con si sten t 2 % of gel ati n sh o ws h o w i t si ts on th e fi br e su r face.
Th e 0 . 2 % of gel ati n an d star ch bin der s si ts bet ween th e fi br es
wh er eas th e al bu men bi n der com pl etel y con ceal s th e fi br es.
23
Figure 1-12 Binder surfaces
THE SILVER NITRATE SENSITIZER
Th e l i gh t sen si ti ve su b stan ce i n sal t an d al bu men pap er i s
si l ver ch l or i de. S il ver ch l or i de is i n sol u bl e i n water . S odi u m
ch l or i de sol u ti on i s c oated on th e paper f ol l o wed by th e si l ver
n i tr ate sol u ti on ,
th u s cr eati n g si l ver
ch l or i de an d sodi u m
n i tr ate. S odi u m n i tr ate i s sol u bl e an d i s wash ed a way du r i n g
th e pr ocessi n g.
Th e
si l ver
n i tr ate
s en si ti z i n g
sol u ti on
wa s
ma de
u si n g
di sti l l ed or de -i on i z ed water . A n y con tami n ati on r esu l ted i n
cl ou dy
wh i te
car bon ate.
Th i s
pr eci pi tate
al so
of
l i mi t ed
s i l ver
th e
ch l or i de
ton al
r an ge
an d
in
si l ver
both
th e
sh ado w an d h i gh l i gh t r egi on s of t h e pr i n t.
S i l ver n i tr ate i n i sol ati on i s n ot l i gh t sen si ti ve . It become s
ph otosen si ti ve
in
th e
pr esen ce
of
su bstan ce s
th at
r eadi l y
ox i di se. Th ese i n cl u de n ot on l y th e sal t sol u ti on s bu t paper
cel l u l ose, gel ati n or star ch .
DECREASE THE SILVER NITRATE P ERCENTAGE
A smal l r edu cti on i n th e p er cen tage of si l ver n i tr ate i n th e
sol u ti on sh o wed ben efi t s i n pr i n ti n g h i gh con tr ast n egati ves.
A s th e per cen tage of si l ver r edu c ed fu r th er , th e pr i n ts became
we ak an d i n effecti ve .
Th e effect of de cr easi n g si l ver n i tr ate:
24
o
1 % sh owe d l i ttl e detai l i n th e h i gh l i gh ts an d th e mi d
ton es decr ease d i n c on tr ast. T h e sh ado w de tai l
was
we ak. S po ts des cr i bed as „mea sl e s‟ appear ed after so me
ti me. M easl es ar e i l l u str ated i n Fi gu r e 1 -1 3 .
o
5 % i n cr eased th e war m th of th e col ou r an d th e pr i n t
beg an to l ose h i gh l i gh t detai l bu t gai n ed sh ado w det ai l .
O
10%
decr eased
th e
con t r ast
and
th e
pr i n t
appear s
war m er i n col ou r . Th e pr i n t was s ti l l sati sfactor y.
INCREASE SILVER NITRATE PERCENTAGE
S mal l i n cr ease s i n th e per cen t age of si l ver n i tr ate i n th e
sol u ti on can be ben efi ci al i n pr in ti n g l ow con tr ast n egati ves .
A s th e per cen tage i n cr eased br on z i n g affect ed th e sh ado w
r egi on s an d yel l o wed th e h i gh l i gh ts , damagi n g th e pr i n t ‟ s
ton al r an ge .
R esu l t s of i n cr easi n g th e si l ver n i tr ate :
o
1 5 % i n cr ease d th e con tr ast . Th e col ou r was c ool er an d
sh o wed
some
l oss
of
detai l
in
th e
sh ado ws .
Th e
h i gh l i gh t detai l wa s m or e appar en t . Th e pr i n t was s ti l l
acceptabl e.
o
2 0 % cr eate d fu r th er i n cr eas e i n th e con tr ast an d fu r th er
l oss of detai l i n th e sh ado ws . Th er e was s ome br on z i n g
an d mor e detai l i n th e h i gh l i gh ts .
o
3 0 % i n cr ease d th e con tr ast , al l owi n g l i ttl e det ai l i n th e
sh ado ws. B r on z i n g beca me obvi ou s wi th l es s detai l i n
th e h i gh l i gh ts. Th e h i gh l i gh ts be came yel l o w.
25
Figure 1-13 Measles
Figure 1-14 Silver Nitrate Variances
Fi gu r e
1 -14
i l lu str ate s
si l ver
n i tr ate
sol u ti on
th e
had
effect
on
di ffer en t
sal t
per cen tages
pr i n t s.
A
2%
of
sodi u m
ch l or i de sol u ti on was u se d i n al l tests .
ADDITIVES TO SILVER NITRATE
Ci tr i c
A ci d
in
th e
si l ver
n i tr ate
sol u ti on
(R ei l l y
1980)
is
su ggested a s a pr eser vati ve of t h e sen si ti sed pa per . Ho wever
i t was f ou n d to pr eci pi tate ou t of th e si l ver n i tr ate sol u ti on
over a per i od of 2 to 3 h ou r s. The paper sen si ti se d wi th ci tr i c
26
aci d
i n cl u ded
e ffect s
th e
l i gh t
sen si ti vi t y,
th e
r esu l ti n g
i mages app ear sl i gh tl y fogged, l o osi n g th ei r fu l l ton al r an ge.
Potassi u m di ch r o mate i n th e si l v er n i tr ate sol u ti on t o i n cr ease
th e
con tr ast,
as
su gges ted
by
(Jame s,
2002)
i mmedi atel y
pr eci pi tates cr eati n g si l ver ch r omate an d pota ssi u m n i tr ate
tu r n i n g th e sol u ti on br i gh t r ed.
E ach
ch an ge
di ffer en ce
obser ved
ci tr ate
in
or
to
wh en
th e
var i ati on
th e
fi n al
i n cl u di n g
sol u ti on .
to
th e
pr i n t.
sal t
sol u ti on
D r amati c
cr eate d
di ffer en ces
pota s si u m di ch r oma te or
Th e
rati o
of
sal t
to
a
wer e
s odi u m
si l ver
al so
per mi tted con tr ol over n ot on l y th e ton al r an ge an d con tr as t
bu t al so th e col ou r . If th e r ati o wa s to o far fr om th e n or m of
2 % sal t sol u ti on an d 1 2 % si l ver n i tr ate sol u ti on th e i mage l os t
ton e an d den si ty.
S i l ver n i tr ate sol u ti on s di d n ot b en efi t fr om an y ad di ti ves . B y
ch an gi n g th e per cen tage of th e si l ver n i tr ate i n th e sol u ti on ,
col ou r s an d th e ton al r an ge wer e con tr ol l ed .
27
Chapter 2 THE PAPER
Th e or i gi n al paper s u sed b y Tal bot wer e 1 0 0 % cotton wr i ti n g
paper
si z ed
wi th
gel a ti n
fr om
th e
J.
Wh at man 's
'Tu r key
M i l l ' . (S ch aaf, 2 0 00 )
Un der stan di n g th e ch ar acter i sti c s of paper wa s essen ti al wh en
deci di n g on paper s to te st . P ape r maki n g can be di vi ded i n to
th e fol l owi n g gr ou ps; h an d mad e, mou l d ma de an d ma ch i n e
made.
H A N D -M A D E : In di vi du al sh eets ar e mad e fr om cott on or l i n en
pu l p
an d
ar e
h an dcr afted
wi t h
l i ttl e
gr ai n
wh i ch
cr eates
gr eater str en gth . Owi n g t o avai l abi l i ty an d ex pen se on l y t wo
wer e ch o sen for th i s r esear ch .
CYLINDER /MOULD-MADE:
M ost wat er col ou r r ag paper s ar e made
fr om 1 0 0 % cotton or l i n e n . Qu a l i ty i s con si s ten t an d easi l y
avai l abl e. M ost of th e test wer e c ar r i ed ou t on th i s paper
M A C H I N E M A D E : Th ese wer e avoi d ed as th ey u su al l y con si st of
wood pu l p, l i gn i n , bl each es an d addi ti ves th at cau se ch e mi cal
foggi n g wh en ap pl yi n g si l ver n i tr ate sol u ti on s .
PAPER COMPOSITION
S IZING:
Th i s
i n cr ease s
su r fac e
str en gth
an d
r esi st s
th e
pen etr ati on of sol u ti on s i n to th e fi br es of th e paper . Gel ati n i s
th e most c om mon t yp e of si z i n g su i tabl e for sal t pr i n ti n g.
S UR FA CE S IZING i n di cates i t i s o n l y si z ed on o n e si de , mos t of
th e tests wer e car r i ed on su r face si z ed paper s .
TUB S IZIN G r efer s t o i m mer si n g dr y fi n i sh ed sh eet i n to a bath
of h ot gel ati n for mi n g a s ki n ov er th e paper su r face wh i ch i s
th en u su al l y h ar den ed .
28
INTE R NA L S IZING i s kn own as be ater or mach i n e. Th e si z i n g i s
added t o th e pr o ces s befor e t h e for mati on
of
th e sh ee ts
(Tu r n er , 19 98 ) .
FIL L E R S
A ND
togeth er ,
L OA D INGS :
fi l l i n g
between
M i n er al
th e
pi gmen ts
gaps
bi n d
cr eati n g
th e
den ser
fi br es
sh eets
(Tu r n er , 19 98 ) . Th ese i n cl u de cal ci u m car bon ate (aci d bu ffer ),
Ch i n a cl ay (kaol i n ), ti tan i u m di o x i de an d opti cal br i gh ten er s.
A l l of th ese r eact ed wi th th e si l ver ch l or i de befor e ex posu r e,
cr eati n g ch emi cal foggi n g .
WA TE R L E A F: Th i s i s th e ter m fo r n o si z i n g , th ese ar e pap er s
ver y absor ben t a n d th er efor e ar e n ot su i tabl e for sal t pr i n ti n g .
Th ey cr eat ed fl at pr i n ts an d u n even col ou r s becau se of th e
i n con si sten t absor pti on r ates of th e sol u ti on s i n to th e pa per .
A l bu men h owe ver seal ed th e su r face of th e pa per th u s maki n g
i t u sabl e .
SURFACE FINISHING
R ou gh : Th i s was di ffi cu l t t o coat an d th e tex tu r e made th e sal t
pr i n t l ook fl at, du e to th e scatt er i n g of l i gh t r efl ect i n g fr om
th i s tex tu r e d su r face .
NOT: Col d pr ess ed , th i s m ean s i t i s n ot h ot pr es sed th r ou gh
r ol l er s. A br u sh was u sed to a p pl y th e coati n g an d a l th ou gh
some acu tan c e was l ost wi th t h e tex tu r e, th i s su r face was
aesth eti cal l y acc eptabl e.
Hot Pr ess : Th e s moo th fi n i sh i s ach i eved by u si n g h ot r ol l er s
or pr essed th r ou gh col d pol i sh ed metal r ol l er s . Th i s su r face
pr ovi de d th e gr eates t ton al r an ge an d acu tan ce. Th e col ou r s
wer e ea si er to eval u ate on th i s ty pe of su r face.
2 4 0 gsm to 3 5 0 gsm wer e easi er to u se f or sal t pr i n ti n g bu t
l i gh ter
wei gh ts
of
1 8 0 gsm
an d
1 4 0 gsm
wer e
te sted
wi th
sati sfact or y r esu l ts . L i gh ter wei gh ts wou l d cu r l an d r equ i r e
tapi n g to a fi r m su r face. 1 40 gsm tor e at ti mes du r i n g th e wet
pr ocessi n g. Th e h eavi er paper s t ook l on ger for fi x er r em oval
to occu r .
29
CARE OF PAPER
Paper s wer e h an dl e d as l i ttl e a s po ssi bl e wi th wh i te cott on
gl oves.
Fi n ger s
l eft
oi l s
an d
sal ts
wh i ch
i n cr e a se d
th e
absor pti on r ate of th e sol u ti on cr eat i n g stai n s on th e pr i n t .
A n y su r face mar k s wer e r e move d gen tl y wi th a soft br u sh or
er aser . D i stu r b i n g th e su r face of th e paper made i t m or e
absor ben t an d appear ed a s a stai n on th e pr i n t .
PAPERS SUITABLE FOR SALT PRINTING:
A l l paper t ests wer e car r i ed o u t u si n g 2 % sodi u m ch l or i de
sol u ti on an d 1 2 % si l ver ni tr ate sol u ti on u si n g th e con tr ol
n egati ve . Th i s u n i for mi ty al l owe d easi er compar i son s bet ween
th e per for man ce s of each of th e paper s. Th e r e su l ts ar e l i s ted
i n or der of th e abi l i ty of th e paper to r epr odu ce a fu l l ton al
r an ge an d acu tan ce . A l l paper s wer e a ci d-fr ee wi th n o op ti cal
br i gh ten er s
an d
Neu tr al
pH.
Th e
fi ve
best
paper s
wer e
magn i fi ed on th e Nova Nan oS E M to vi ew th ei r str u ctu r e. Th e
col ou r step - we dge s an d tabl e s h el p to an al yses col ou r s . Th e
poi n ter mar ks th e mi d-t on e an d sh ado ws on th e ste p - we dge
an d establ i sh es th e pa per base co l ou r .
B E R GGE R COT 3 20 M OUL D M A D E 3 2 0 gsm HP 1 0 0 %. Th i s paper
wa s
n ot
avai l abl e
in
A u str al i a
an d
th e
test
sh eet s
wer e
pu r c h ased di r ectl y fr om th e pa pe r wh ol esal er i n Fr an ce .
Th e h i gh magn i fi cati on s as sh o wn i n Fi gu r e 2 -1 i n di cates th e
l ar ge amou n t of gel ati n si z i n g. Wh en h ot pr essed i t pr ovi des a
h ar d
su r face.
Th i s
h ar d
co mp r essed
su r face
cr eates
th e
cool n es s of th e pr i n t.
C ol ou r , T on es, a n d App ea ra n c e : Th e s al t pr i n t r esu l t ed i n a
cool deep br o wn col ou r . It h el d th e ton es i n both h i gh l i ght
an d sh ado ws , sh o wi n g 1 9 cl ear steps.
TA L B OT HA ND M A D E 2 40 gsm 1 0 0 % cotton h eavi l y gel ati n tu b
si z ed . Th i s i s n o t avai l abl e i n A u str al i a an d sa mpl e s wer e
pu r ch ased fr om th e R u sco mbe M i l l i n Fr an ce.
30
Hi gh magn i fi cati on s Fi gu r e 2 -2 sh o ws th e l ar ge amou n t o f
gel ati n si z i n g ; both i n an d on t h e su r face. Th i s h as n ot been
h ot pr ess ed l i ke th e B er gger paper , th e gel ati n r emai n s soft
n atu r al l y el ev ati n g th e si l ver ch lor i de pr ovi d i n g an ex tr emel y
war m col ou r .
C ol ou r , T on es , an d App ea ra n c e: Th e sal t pr i n t wa s a r i ch war m
br own col ou r . It h el d th e t on es i n both h i gh l i gh t an d sh ad o ws
sh o wi n g 1 9 cl ear steps.
Th e Tal bot si z i n g was i n con si sten t
wi th so me fl a ws an d s pec k s th r ou gh ou t th e su r face . It wa s
i n con si sten t i n i ts per for man ce bu t th e qu al i ty of su cces sfu l
pr i n ts made i t wor th per si sti n g . Th e su r face beca me ver y s oft
wh en co ati n g th e sal t sol u ti on s. To en su r e an even coati n g of
si l ver n i tr ate sol u t i on th e sal ted paper was l eft t o „cu r e‟ for
2 4 h ou r s befor e sen si ti si n g .
Th is l i gh ter wei gh t pap er cu r l ed
wh en moi stu r e wa s ap pl i ed an d n eed ed to be se cu r ed wh i l e
coati n g.
A R CHE S PL A TINE
M OUL D M A D E (Fr en ch ) 3 1 0 gsm HP 1 0 0 %
cotton . Th e am ou n t of gel ati n s e en i n Fi gu r e 2 -3 , i s l es s th an
th e pr evi ou s t wo pa per s. A l th ou gh th i s com pr esse d su r face
cr eates co ol ton ed pr i n ts i t di d n ot el evate th e i m ages t o th e
same degr ee du e t o th e smal l er a mou n t of si z i n g.
C ol ou r , T on es P ap er App ea ra n ce: Th e sal t pr i n t wa s a c ool
br own col ou r . It h el d th e t on es i n both h i gh l i gh t an d sh ad o ws
sh o wi n g 1 8 cl ear steps. It h el d th e ton es ex tr emel y wel l an d
wa s con si sten t i n i ts per for man ce an d qu al i ty.
FA B R IA NO A R TIS TICO M O UL D M A D E (Ital i an ) 3 0 0 gsm HP 1 0 0 %
cotton . Th e gel ati n si z i n g a ppe ar s to be l ess th an pr evi ou s
paper s an d i r r egu l ar i n i ts cove r age (Fi gu r e 2 -4 ). Th e i mage
si ts i n th e fi br es wh i ch cu r bs th e ton al r an ge . Th e cr eam paper
col ou r base ma de th e t on es app e ar war mer .
C ol ou r T on es a n d Ap p ea r an c e : Th e paper wa s war m i n co l ou r
so th e h i gh l i gh ts wer e n ot as cl e an as th e pr evi ou s paper s . I t
h el d th e ton es i n bo th h i gh l i gh t an d sh ado ws sh o wi n g 1 6 cl ear
steps. Th e su r face si z i n g h el d th e ton es wel l .
31
B UXTON HA ND M A D E PL A TINOT YP E 2 4 0 gsm 1 0 0 % cotton HP .
Th i s i s u n -bu ffer ed an d i n ter n al l y si z ed wi th A l kyl -keten e di mer (A K D ) , a syn th eti c ar ch i val i n ter n al si z i n g agen t ; th i s i s
a
h ydr oph obi c
or
water
r ep el l en t
si z i n g.
Pr odu ced
in
R u scombe M i l l Fr an ce
Th e h i gh magn i fi cati on s i n Fi gure 2 -5 sh ow th e l ar ge amou n t
syn th eti c si z i n g. Th e i mage i s el evated by both th e si z i n g an d
th e al bu men bi n der . Th e tex tu re an d sl i gh t gl oss pr odu ce d
qu i te di ffer en t r esu l t to o th er p aper s. Th e ste p - wedge Fi gu r e
2 -1 0 i s al bu men coate d, al th ou gh n ot con si sten t wi th th e oth er
step we dges th e ch e mi cal foggi n g of th e sal t pr i n t wou l d n ot
al l ow a tr u e co mpar i son of th e t o n al r an ge .
C ol ou r , T on es a n d App ea ra nc e: Th i s paper wor ked ex tr emel y
wel l f or al bu men pr i n ti n g . It pr ovi ded r i ch pu r pl e br o wn ton es
wi th a fu l l ton al r an ge. B u x ton paper was n ot su i tabl e for sal t
pr i n ti n g . Wh en th e si l ver n i tr ate sol u ti on was appl i e d to th e
sal ted paper t h e A K D cr eated a ch emi cal fog , r edu ci n g th e
h i gh l i gh ts
an d
fl atten i n g
th e
sh ado w
r egi on s .
A l bu men
pr otected l ayer pr even t s th e si l ver n i tr ate fr om r each i n g th e
paper .
Figure 2-1 Bergger Paper High Magnifications
32
Figure 2-2 Talbot Paper High Magnifications
Figure 2-3 Arches Platine High Magnifications
Figure 2-4 Fabriano Artistico High Magnifications
Figure 2-5 Buxton Paper High Magnifications
33
Figure 2-6 Bergger Paper
Figure 2-7 Talbot Paper
Figure 2-8 Arches Platine
Figure 2-9 Fabriano Artistico
Figure 2-10 Buxton Paper
Be r g g e r P ape r
L*
a.
b.
S h ado ws
P anto ne ®
S o l i d M att
B l ack m
12
1
0
M i d-ton es
11 m
42
4
7
Hi gh l i gh ts
7 4 99 m
92
-1
12
Paper base
7 4 85 m
90
-5
7
S h ado ws
145 m
20
17
23
M i d-ton es
4 6 35
45
19
30
Hi gh l i gh ts
670 m
94
-2
21
Paper base
7 4 99 m
92
-1
12
S h ado ws
4 9 75 m
17
19
8
M i d-ton es
10 m
47
4
6
Hi gh l i gh ts
7 4 99 m
92
-1
12
Paper base
7 4 99 m
92
-1
12
T al bo t P ape r
Ar c he s Pl ati ne
34
Fabr i ano Ar ti sti c o
S h ado ws
4 6 25 m
20
16
18
M i d-ton es
875 m
52
12
22
Hi gh l i gh ts
670 m
94
-2
21
Paper base
607 m
92
-4
21
S h ado ws
B l ack m
12
1
0
M i d-ton es
7 5 18 m
40
11
10
Hi gh l i gh ts
7 4 01 m
92
1
18
Paper base
7 4 99 m
92
-1
14
Buxton Paper
Table 2-1 Paper Colours
Oth er paper s test ed :
S A UND E R S WA TE R FOR D (E n gl i sh ) 3 0 0 , an d 1 50 gsm HP 1 0 0 %
cotton . Th i s h el d ton e s wel l an d offer s ver y war m ton al r an ge.
It l ost th e h i gh l i gh ts to th e war m ton es of th e paper .
R IS ING S TONE HE NGE M A CHINE M A D E
(E n gl i sh ) 2 4 5 gsm NOT
1 0 0 % cotton . A s i t i s bu ffer ed wi th cal ci u m car bon at e th e
sen si ti vi ty of si l ver n i tr ate cau se d foggi n g. Th e paper wa s
absor ben t cr eati n g a du l l pr i n t . A l bu men was n ot affect e d a s i t
i sol ates th e pa per fr om th e si l ver n i tr ate sol u ti on .
A R CHE S A QUA R E LL E M OUL D M AD E (Fr en ch ) 3 0 0 gsm H P 1 0 0%
cotton . Th i s i s an u n -bu ffer ed paper , i n ter n al l y an d su r face
si z ed wi th gel ati n e . It pr ovi d ed a r eason abl e ton al r an ge wi th
pl easan t war m ton e s.
FA B R IA NO TIE PE L O M OUL D M A D E Water col ou r ( Ital i an ) 2 9 0 gsm
1 0 0 % cot ton an d i n ter n al l y si z ed .
It
wa s
sof t
th er efor e
su r faced
u n su i tabl e
paper
for
Th i s was wel l pr i ced paper .
wi th
pl ai n
a
sal ted
h i gh
absor pti on
pr i n ts .
Th e
r ate
r esu l ts
i mpr ove d wi th gel ati n an d al bu m en sol u ti on s.
35
L A NA QUA L L E M OUL D M A DE , 3 0 0gsm HP , 1 0 0 % cotton . Th i s i s
u n -bu ffer ed, i n ter n al an d ex ter nal l y si z ed wi th A K D . It i s w el l
pr i ced bu t th e r esu l ts wer e di s appoi n ti n g . Th e pr i n ts wer e
bl otch y du e to u n even abs or pti on ; even wh en bi n der s wer e
u sed i n th e sal t sol u ti on .
CR A NE ‟ S D IPL OM A PAR CHM E NT (US A ) (r epl acemen t for Cr an es
Pl ati n otype) M A CH I NE M A D E 1 7 7 gsm HP 1 0 0 % cotton r o si n an d
al u m si z ed. Th i s gave a r eason ab l e r esu l t bu t th e l i gh t wei gh t
paper t or e easi l y ma ki n g pr oces si n g di ffi cu l t.
CR A NE
K ID
FINIS H 17 7
gsm 10 0 % cotton
u n -pr essed .
Th i s
l i gh twei gh t paper n ee ded car efu l h an dl i n g wh en coa ti n g an d
pr ocessi n g .
ADDING SIZING TO PAPER
Th er e wer e ad van tages i n si z i n g paper befor e coati n g wi th th e
sal t sol u ti on s.
1 . It al l owe d u se of por ou s paper s t h at wer e n ot oth er wi se pr esi z ed.
2 . It cr eate d a di ffer en t fi n i sh to th e su r face .
3 . P aper s th at wer e h i gh l y tex tu r ed cou l d be u sed .
4 . Th i s was u sed a s a meth o d to c on tr ol th e col ou r .
Th e di ffer en t si z i n g tested:
o
Gel ati n .
o
Gel ati n h ar den ed wi th gl yox al .
Th e gel ati n si z i n g sol u ti on was kept ab ove 2 0 ° C or i t di d n ot
coat even l y . A sec on d co at of gel ati n assi st e d wi th coa ti n g
sol u ti on s on r ou gh tex tu r ed su r faces .
S i z i n g pr even t ed sol u ti on s fr om soaki n g i n to th e p aper maki n g
th e coati n g mor e u n i for m . A l thou gh h ot pr ess paper s wi th
h ar d su r faces ga ve th e sal t pr i n t s a bet ter defi n i ti on wi th a
cool col ou r , paper s wi th h eav y gel ati n si z i n g su ch as Tal bot
al so pr ovi ded war m col ou r s bu t s ti l l wi th a l on g ton al r an ge .
36
HARDENING THE GELATIN SIZING
Un for tu n atel y t h e ch e mi cal s u s ed for h ar den i n g gel ati n ar e
dan ger ou s .
A ddi n g sodi u m car bon ate to gl y ox al cr eates an al kal i n e b ath .
Th i s assi st s bi n di n g bet ween th e si z i n g an d th e h ar den er , the
h i gh pH max i mi s es th e h ar den i n g (Wal l s an d A ttr i dge, 1 9 77 ) .
Testi n g di sc over ed so di u m car bon ate r emai n ed i n th e paper
an d cr eated a ch emi cal foggi n g i n th e sal t pr i n t th er efor e
sodi u m car bon ate cou l d n ot be i n cl u ded.
100%
c otton
pr oved
to
be
th e
most
stabl e
ba se
for
sal t
pr i n ti n g. Paper s made fr om ot h er fi br es wer e fou n d to b e
u n su i tabl e, r eacti n g wi th th e si l ver to cr eate a ch emi cal fog.
A n y addi ti ves apar t fr om gel ati n si z i n g, act as an ox i dan t wi th
th e si l ver ch l or i de
cau si n g a ch emi cal fog,
maki n g
al bu men
si l ver .
ch l or i de
fr om
An
r each i n g
th e
coati n g
pa per
or n on i mag e
pr even ted
su r face
th e
si l ver
al l o wi n g
paper
n or mal l y n ot su i tabl e for sal t pr i n ti n g to be u sed.
Temper atu r e an d h u mi di ty i n fl u en ced th e absor pti on r ate of
th e sol u ti on s . Pa per s th at h ad l i ttl e or n o si z i n g wer e qu i te
por ou s an d th e s ol u ti on s s u n k i n to th ese types of pa per s .
Th ese
ma de
th e
i mage
l oo k
s ofter ,
cr eati n g
a
du l l
ma tt
appear an ce .
Tex tu r ed paper s wer e m or e di f fi cu l t to coat bu t th i s was
over come by u si n g a br u sh to ap pl y th e s ol u ti on or si z i n g wi th
gel ati n befor e addi n g th e sol u tion s . Th e l i gh t scatter s fr om
th e tex tu r ed su r face s an d fl atten ed th e i mage appear an ce.
37
Chapter 3 COATING
THE
PAPER
E n su r i n g th at th e sal t pr i n t coat i n g i s e ven an d c on si st en t i s
i mpor tan t t o eval u ati n g th e to n al r an ge an d col ou r s. Th i s
ch apter ex pl or e d ways of coati n g an d th ei r effects.
Coati n g paper can be br o ken i n to 3 basi c meth od s ; fl oati n g th e
paper i n a ba th of sol u ti on , b r u sh i n g on , or pu sh i n g th e
sol u ti on wi th a gl ass r od.
FL OA TING OR S UB M E R GING IN A S OL UTIO N B A TH : Th e paper
can be compl etel y su bm er ged, or fl oat on th e su r face o f th e
sol u ti on . S u bmer si on i n th e sal t sol u ti on cr eate d a fl at i mage
as th e si l ver seem e d to si t d e eper i n to th e paper . It was
di ffi cu l t to es ti mate th e amou n t of sol u ti on th at was ab sor bed
wh en fl oati n g th e paper on th e sol u ti on . C oati n g th e si l ver
n i tr ate i n th e bath was n ot atte mpted du e t o th e dan ger of
h an dl i n g l ar ge qu an ti ti es of th i s sol u ti on .
B R US HING : B r u sh es wi th n o met al par ts mu st be u sed as th e
metal r eacts wi th th e sol u ti on s . Th e ex ampl es tes ted wer e
h ake br u sh , spon ge br u sh es an d B u ckl e br u sh es (cotto n wool
twi sted i n t o a test tu be) . Car e wa s n eede d to en su r e th e
coati n g was even an d i t wa s di ffi cu l t to esti mate t h e amou n t
of sol u ti on u sed t o coa t th e paper . Th i s me th od was n o t
econ omi c al as th e br u sh r etai n ed some of th e sol u ti on .
PUS HING OR D R A GGING THE S OL UTIO N : Gl as s pu ddl e pu sh er s
or ch emi cal pu sh er s pu sh a pool of th e sol u ti on even l y acr oss
th e paper . B y measu r i n g th e sol u ti on ou t wi th a syr i n ge th i s
coati n g sys tem wa s econ omi c, fas t an d r el ati vel y pr eci se.
CHEMICAL PUSHERS
Hei n er Peter sen of Peter sen S ci en ti fi c Gl ass ma de th e fi r st test
ch emi cal pu sh er s f or th i s pr oject . Th ese wer e ma de fr om gl a ss
r ods
1 0 mm
A l th ou gh
in
di amet er
r el ati vel y
wi th
a
su ccess fu l ,
cen tr al
th ey
h an dl e
wer e
n ot
at tach ed.
al wa ys
38
compl e tel y str ai gh t , l eavi n g ar eas wi th n o sol u ti on on th e
paper .
Hei n er
su ggested
con ver sati on on 6
th
du r i n g
a
tel eph on e
of Ju n e 2 0 0 6 to u se r ou n d
gl ass t u bes kn o wn as capi l l ar y gl ass , 1 0 mm i n
di ameter
wi th
2 mm
wal l s
as
i l l u str ated
in
Fi gu r e 3 -1 Th ese wer e ben t i n to a tr i an gu l ar
sh ape so th ey cou l d be h el d wi th on e h an d .
Figure 3-1 Glass Rod
SALT COATING
Th e amou n t of s ol u ti on r equ i r ed ch an ge d wi th :
1 . Hu mi di ty .
2 . Heat.
3 . Paper su r fa ce.
Wh en u si n g a h i gh er per cen tage of gel ati n i n th e sal t sol u ti on ,
th e paper an d th e s ol u ti on wer e h eated to 2 0 ° C. Th i s s top ped
th e on set of th e gel ati n setti n g an d „dr aggi n g ‟ u n even l y do wn
th e paper . In cr easi n g th e qu anti ty of fl u i d appl i ed to th e
paper al so ease s th i s pr obl em.
A l l owi n g th e s ol u ti on to soak i n befor e u si n g war m ai r to dr y
th e paper gav e a mor e c on si sten t an d even su r face. A ppl yi n g
ex cessi ve h eat wh i l e sti l l qu i te damp , dr i ed th e sal t on th e
su r face l eavi n g sal t cr ystal tr ai l s or patch es.
ALBUMEN COATING
A l bu men wa s mor e di ffi cu l t t o coat th an pl ai n sal t ed paper .
B u bbl es an d l u mp s of sol u ti on cr eate d dar k spo ts an d ci r cl es.
Un even pat ch es sh o wed as di ff er i n g den si ti es i n th e fi n al
pr i n t. Th er e was var i ati on fr om on e sol u ti on to an oth er , some
bei n g qu i te gl u ten ou s an d sti cky. Th i s i s du e to th e h en ‟ s di et
wh i ch af fects
th e wh i te of th e egg.
A ddi n g a l i ttl e mor e
39
di sti l l ed wat er u su al l y sol v ed th i s pr obl em. Coati n g was f ou n d
easi er wh en th e fol l o wi n g step s wer e ta ken .
o
In cr easi n g
th e
a mou n t
of
sol u ti on
appl i ed.
Th e
ex cess s ol u ti on al l o ws c on tr ol o ver th e smooth n e ss
of th e coati n g.
o
A ddi n g 0 . 5 % of wetti n g agen t t o t h e al bu men sol u ti on
wa s su gges ted i n som e tex t s to r edu ce ai r bu bbl es
(R ei l l y, 1 98 0 ) . In pr acti ce n o si gn i fi can t di ffer en ce
wa s fou n d .
o
R emov i n g an y ex ce ss al bu men a r ou n d th e edges of
th e pr i n t; th e ex ces s for m s h ar d l u mps wh i ch mad e i t
di ffi cu l t to move th e r od even l y acr oss th e paper
wh en ap pl yi n g th e si l ver n i tr ate sol u ti on .
Th e ease of c oati n g i n cr eases a s th e al bu men ages. (Webb an d
R eed, 2 0 0 0 ) state th at th e sol u ti on can be u sed i mme di atel y.
Ho wever oth er tex ts su gge st th a t after th e fi r st twen ty f ou r
h ou r s i t sh ou l d be fi l ter ed th r ou gh ch eesecl oth , fol l o wed b y a
fer men tati on
per i od
of
t wo
da ys
(Ja mes,
2002)
on e
week
(Far ber , 19 9 8 , R ei l l y, 1 9 80 ) and M i ke R obi n son i n B ar n i er,
(2 0 00 ) .
A gl ossi er fi n i sh f or th e al bu men wa s cr eated by dr yi n g th e
su r face at a bou t 3 0 ° C .
Th e si l ver n i tr ate coati n g s ets o r coagu l ates th e fi r st coati n g
so th er e was n o n eed t o h ar den th i s u n l ess a se con d coat of
al bu men wa s pr efer r ed .
A secon d coat i n cr eases th e su r face
gl oss, th er eby pr odu ci n g an ex tr a br i l l i an ce to th e al bu men
pr i n t.
Har den i n g
is
e ssen ti al
to
avoi d
s often i n g
th e
fi r st
al bu men coat wh i l e appl yi n g th e secon d.
Th e fol l o wi n g meth o ds of h ar den i n g wer e test ed:
1 . S tor i n g
for
fou r
mon th s
en su r ed
th e
al bu men
wa s
su ffi ci en tl y „cu r ed‟ an d was h a r d en ou gh to accept a
secon d c oat .
40
2 . S teami n g th e su r face of th e fi r st coati n g for 1 mi n u te.
(Far ber , 1 99 8 ) . Th e si l ver n i tr ate sol u ti on soften e d th e
al bu men sol u ti on i n l es s th an on e mi n u te . Th er efor e wa s
n ot con si der ed su cces sfu l .
3 . Pl ace a pi ece of paper
al bu men
coated
over
paper .
S et
th e su r face of th e dr y
an
i r on
at
max i mu m
temper atu r e an d move even l y o ver th i s paper (James,
2 0 02 ) . Th e si l ver n i tr ate s ol u ti o n soften e d th e al bu men
sol u ti on i n l ess th an on e mi n u te . Th er efor e th i s was n ot
con si der ed su c ces sfu l .
4 . Pl aci n g th e pr i n t i n a bath of 7 0 % i sopr op yl al coh ol f or
1 5 secon ds . Th i s me th od was co n ven i en t as th er e i s n o
wai ti n g ti me an d i t pr oved to per for m as wel l as th e
agei n g meth od.
M ost tex t s advi se th at 2 % am mon i u m ch l or i de sh ou l d b e adde d
to t h e bath of i sopr o pyl al coh ol
as th e bath l ea ch es th e
ch l or i de fr om th e fi r st c oati n g (Jame s, 2 0 0 2 ) (R ei l l y, 1 98 0 )
r ei ter ated by Far ber 1 9 9 8 , an d Mi ke R obi n son (B ar n i er , 2 0 0 0 ).
Nu mer ou s test s wer e car r i ed ou t pr ovi n g th e added ch l or i de
i n cr eased ex po su r e ti me dr amati cal l y an d th e pr i n t was pal e
an d
weak.
Th e
con si der abl y.
ex tr a
R ei l l y
su ggested th at i t
ch l or i de
(emai l
wa s a
18 t h
„ mi sta ke ‟
decr ea sed
D ecember
th e
2 0 07 )
con tr as t
str on gl y
to add ch l or i de to th e
i sopr opyl al c oh ol ; th i s appear s to con tr adi ct h i s 1 9 8 0 tex t.
ARROWROOT (STARCH) COATING
E ven after fi n di n g a for mu l a th at gave con si sten t coati n gs ,
ar r owr oot sti l l pr oved t o be th e most di ffi cu l t sol u ti on t o
coat . Th i s di ffi cu l ty was r esol ve d by i n cr easi n g th e amou n t of
sol u ti on appl i e d to 6 ml for an 8 x 1 0 pr i n t. 3 ml s i s appl i ed at
th e top
of th e
page
an d 3 ml
of s ol u ti on
at
th e bo tto m ,
pr ovi di n g an even coati n g .
41
A defi n ed mar k was l ef t on th e paper i f th e r od stop ped
pu sh i n g fl u i d i n th e i mage ar ea, even for a fe w se con ds.
Th i s
wa s du e to th e r api d abs or pti o n cr eated b y a mmon i a. Paper
sen si ti sed
l es s
th an
th r ee
h ou r s
after
th e
s tar ch
coati n g
decr eased ex posu r e ti mes b y 5 0 % . Th i s was du e to a mm on i a
i n cr eas i n g th e sen si ti vi ty of th e si l ver ch l or i de .
r api d absor pti on r ate of th e si l ver n i tr ate
Th er e was a
sol u ti on i f th e
ar r owr oot c oati n g was n ot l eft t o „cu r e‟ . Un l ess th er e was a
su bstan ti al i n cr ease of th e si l ve r n i tr ate sol u ti on t h e c oati n g
wa s u n even .
of
t wel ve
L eavi n g th e coate d paper to cu r e for a mi n i mu m
h ou r s
pr ovi de d
a
stabl e
su r face
wi th
n or mal
ex posu r e ti mes.
SENSITIZING THE SALTED PAPER
A s th e si l ver n i tr ate sol u ti on i s appl i ed th e paper become s
l i gh t sen si ti ve to u l tr a vi ol et l i gh t an d th e vi si bl e spe ctr u m u p
to 6 4 5 n m. A 5 0 watt i n can descen t l i gh t wa s se t at 1 . 5 m fr om
th e
wor ki n g
su r face s
wh er e
s en si ti si n g
was
car r i ed
ou t .
Fl u or escen t l i gh ts wer e en cased wi th a UV fi l m bl o cki n g th e
spectr al l i gh t r ays bel ow 4 0 0 nm. Tests wer e per for med to
en su r e n o l i gh t wou l d „fog ‟ th e sal t pr i n t du r i n g sh or t peri od
of ti me (u p to fi ve mi n u tes) r e qu i r ed du r i n g th e sen si ti z i ng
step. Th e sen si ti sed paper was s tor ed i n th e dar k u n ti l r eady
for u se.
E ar l i er meth ods of sen si ti si n g wer e per for med by fl oa ti n g th e
sal ted pa per on th e su r face of a bath of si l ver n i tr ate sol u ti on .
Th i s
is
con si d er ed
a
dan ger o u s
pr acti ce
an d
a
wa stefu l
meth od, u si n g l ar ge amou n t s of si l ver n i tr ate. A n u mber of
tex ts i n cl u di n g (Ja mes, 2 0 0 2 ) (R ei l l y, 1 9 80 , B ar ni er , 20 0 0 ) and
(B ar n i er , 20 0 0 ) sti l l today r eco m men d th i s me th od. Cr a wfor d
(1 9 79 ) fool i sh l y su gges ts th at i t i s con si d er ed a badg e of
h on ou r to stai n you h an ds wi th si l ver n i tr ate !
Th e u se of a gl ass r od an d th e syr i n ge meth od of coa ti n g
pr oved to be th e safes t meth od avoi di n g al l con tact wi th th e
42
si l ver n i tr ate sol u ti on . Th e same qu an ti ty of si l ver n i tr ate
sol u ti on i s u sed a s for th e sal t sol u ti on . Th er efor e i f 2 ml of
sal t sol u ti on i s u sed th en 2 ml of si l ver n i tr ate sol u ti on wa s
al so appl i ed .
B y u si n g a g l ass r od an d a syr i n ge ( wi th ou t th e n eedl e ) i t was
easy to c on tr ol th e amou n t of si l ver n i tr ate sol u ti on appl i ed.
Th e ex act a mou n t of si l ver n i tr ate sol u ti on can be dr a wn u p
i n to
th e
syr i n ge
fr om
th e
bo t tl e.
On ce
pr acti se d
at
th i s
meth od, th e c oats be ca me ev en , th e r ati o bet ween th e sal t an d
th e si l ver n i tr ate sol u ti on
was con tr ol l ed an d th e coa ti n g
dr i ed qu i ckl y.
Coa ti n g th e si l ver n i tr ate on t o th e dr y so di u m ch l or i de c oati n g
cr eat es si l ver ch l or i de , th e i m agi n g maki n g com pou n d an d
sodi u m n i tr ate wh i ch mu st be wa sh ed ou t of th e pr i n t after
ex posu r e.
SENSITIZING ALBUMEN P APER
o As
wi th
th e
al bu men
ch l or i de
sol u ti on ,
i n cr easi n g
th e
amou n t of si l ver i n th e syr i n ge o r on th e br u sh en su r e d easy
appl i cati on , al so mi n i mi s i n g th e bu bbl es. Th e bu bbl es ar e
cr eated by th e sof ten i n g of th e al bu men sol u ti on .
o E ach bu bbl e r emai n i n g on th e paper l eft a dar k ci r cl e i n th e
i mage.
SENSITIZING ARROWROOT PAP ER
Ci tr i c aci d i n th e si l ver n i tr ate s ol u ti on i s sai d t o decr eas e th e
ex posu r e ti me an d d ecr ease th e con tr ast . Wh i l e i n cr easi n g
sen si ti vi ty, th e ci tr i c aci d i n th e si l ver n i tr ate sol u ti on make s
th e paper mor e di ffi cu l t t o t o n e (Cr a wfor d, 1 9 7 9 ) . A ddi n g
ci tr i c
aci d
to
th e
si l ver
n i tr ate
sol u ti on
decr ease d
th e
ex posu r e ti me an d br on z i n g became an i ssu e i n th e sh adow
r egi on s. Th i s appear s to con tr adi ct th e n eed t o i n cr eased
sen si ti vi ty of th e si l ver n i tr ate sol u ti on .
R ei l l y states th at a r r owr o ot r equ i r es a str on ger si l ver n i tr ate
coati n g an d n eed s to be a ppl i e d r api dl y du e to th e star ch ‟ s
43
sol u bi l i ty (R ei l l y, 1 9 80 ) . In pr acti ce h o wever , i t was fou n d
u n n ecessar y to i n cr ease th e str en gth of
th e si l ver n i tr ate
sol u ti on . Th e coa ti n g pr obl em wa s s ol ved b y appl yi n g an
i n cr eased am ou n t of th e si l ver n i tr ate sol u ti on an d dr ai n i n g
off th e ex cess.
STORAGE OF SENSITIZED PAPER
Tr i al s pr oved th at stor i n g sen si ti z ed paper du l l s th e pr i n t.
S ome
ch emi cal
f oggi n g
appear s
temper atu r e an d h u mi di ty.
after
ti me,
dep en di n g
on
T h e h i gh l i gh ts l os t th ei r cl ar i ty
an d th er e was l o ss of o ver al l den si ty an d sen si ti vi t y to l i gh t.
A l bu men star t ed to sh o w yel l o w i n g i n th e hi gh l i gh ts. It was
fou n d th at s tor i n g i n tem per at u r es bel o w 5 ° C l o wer ed th e
sen si ti vi ty an d th e foggi n g cou l d be del ayed for u p to fou r
h ou r s.
In su mm ar y g l as s r ods wer e f ou n d to b e an e con o mi c, pr eci se,
fast an d eas y m eth od for co ati n g an d ea si l y wa sh ed to r em ov e
al l ch emi cal tr ace s. Ho wever gl a ss r od s wer e n ot su i tabl e for
h i gh l y tex tu r ed su r faces . Pu sh i n g th e fl u i d do wn th e paper can
be di ffi cu l t an d th e r od may „br u i se‟ th e peaks o f th e tex tu r e .
On ce th e ch l or i de was o mi tted fr om i sopr o pyl al coh ol for
h ar den i n g th e al bu men th i s was c on si sten tl y su cces sfu l wh en
appl yi n g th e secon d coat.
L eavi n g th e most sa l te d paper to cu r e for twen ty -fou r h ou r s
r edu ced th e moi stu r e con t en t pr o vi di n g a mor e stabl e coati n g
su r face for th e si l ver n i tr ate sol u ti on . D espi te l i ter atu r e to th e
con tr ar y, s tor age of sen si ti sed pa per wa s u n sati sfact or y o wi n g
to th e decr ease i n sen si ti vi t y an d foggi n g.
44
Chapter 4 THE
NEGATIVE
Th e sal t pr i n t i s a con tact pr o c ess r equ i r i n g a n egati ve th e
same si z e as th e desi r ed pr i n t. E x p o s u r e s a r e c o n s i d e r a b l y l o n g e r
than processed out papers, minutes to hours as opposed to seconds
i n a n e n l a r g e r . T h e e n l a r g e r l i g h t i s n o t s t r o n g e n ou g h t o e x p o s e
s a l t p r i n t s . U V i s r e q u i r e d f o r e x p o s u r e a n d t h e n e g a t i v e m u s t b e in
“c o n t a c t ” wi t h t h e s e n s i t i s e d p a p e r .
Th e n egati ve s wer e ex pose d on 8 x 1 0 fil m to h el p ampl i f y
di ffer en ce s bet ween ea ch fi l m t y pe.
A ste p we dge wa s pl ac ed
i n th e i mage , l ar ge en ou gh to r ead on a den si to meter .
Th i s
el i mi n ated th e n eed to en l ar g e th e i mag e , mi n i mi z i n g an y
ar tefacts th e di gi tal scan may i n tr odu c e. Th e most su cces sfu l
an al ogu e fi l m n egati ve was sel ec ted as th e con tr ol t o com par e
al l oth er n egati ve types .
S el f -mas ki n g
is
fu n damen t al
in
pr odu ci n g
th e
sal t
pr i n t ‟ s
ex ten ded ton al r an ge. Th i s i s cr eated by t h e si l ver ch l or i de
con ver t i n g to metal l i c si l ver du r i n g ex posu r e , th u s bl ocki n g
th e sh ado w ar eas ( th e l i gh t par t of th e n egati ve). Th i s sl o ws
th e ex posu r e to th e sh ad o w r egi o n al l owi n g th e h i gh l i gh ts ( th e
den se/ dar k par t of th e n e gati v e) to con ti n u e pr i n ti n g. Th e
sel f -ma ski n g per mi t s a gr adati o n of l i gh t ton es wh i l e sti l l
h ol di n g sh ado w d etai l . Cor r ect n egati ve den si ty i s th er efor e
i mpor tan t for th e h i gh l i gh ts so t h ese l i gh ter ton es do n o t over
ex pose. Negati ve s, wh eth er di gi t al or an al ogu e, ar e cr i ti cal to
th e pr i n t s t on al r an ge. Th i s ch apter ex pl or es th e di ffer en t
wa ys of pr o du ci n g n egati ves.
TYPES OF NEGATIVES
A l th ou gh n egati ves fal l i n to two major gr ou ps , an al ogu e an d
di gi tal , th ese gr ou ps do i n ter l ace . A n an al ogu e n egati ve can be
pr odu ced fr o m a di gi tal fi l e an d an al ogu e n egati v es can be
di gi ti sed to cr eate i n kj et n egati v es.
45
ANALOGUE CONTINUOUS TONE FILM NEGATIVES
A n al ogu e n egati ve s h ave tr adi ti on al l y pr ovi de d an ex cel l en t
con ti n u ou s ton e. D evel o pmen t c on tr ol s can pr ovi de th e ex tr a
den si ty r equ i r ed for sal t pr i n ts.
Cer tai n di sadvan tag es c ome wi t h u si n g fi l m. Th e n u mber o f
bl ack an d wh i te fi l m s avai l abl e o n th e mar ket h as con ti n u ed t o
decl i n e si n ce th e i n tr odu cti on
of di gi tal
captu r e camer as.
3 5 mm an d medi u m for mat fi l ms mu st be en l ar ged for con tact
pr i n ti n g by mean s of i n t er -n eg ati ves or r ever se pr oc essi n g.
Th ese mater i al s ar e ex pen si ve
an d dar kr oo m f aci l i t i es f or
pr ocessi n g ar e r eq u i r ed.
FILMS TESTED
I L F O R D FP4 F I L M 12 5 IS O Th i s fi l m cr eate d a wi de t on al r an ge
ex ten ded by th e ch ar acter i sti c l o w fi l m bas e fog . A s a r e su l t of
th i s l o w fi l m base fog an d sl o wer spee d Il f or d‟ s HP4 fi l m
offer ed
th e
best
r esu l t
wi th
most
d evel oper s.
Te sts
wer e
car r i ed ou t at 8 0 IS O, 1 0 0 IS O, 1 25 IS O an d 2 00 IS O
o
I L F O R D HP5 40 0 IS O. Th i s fi l m offer s
S i mi l ar
qu al i ti es to
th e Il for d FP4 fi l m . Ho we ver th e fi l m ba se wa s n ot as
cl ear an d di d n ot ex ten d th e t on al r an ge to th e sa me
degr ee . Th i s was te sted at 2 5 0 ISO an d 4 5 0 IS O
o
F O M A P A N C L A S S I C 2 0 0 IS O. Th e PMK devel oper war med th e
n egati ve col ou r . Ho wever th i s f i l m emu l si on an d base
fog com pr esse d th e sal t pr i n t ton al r an ge.
o
F O R T E F O R T E P A N 1 0 0 IS O fi l m r ated at 1 0 0 an d 20 0 IS O
B ase fog l i mi ted th e ton al r an ge cr eat i n g si mi l ar r esu l ts
to
Fomap an ,
agai n
compr es si n g
th e
sal t
pr i n t
ton al
r an ge .
o
F O R T E F O R T E P A N 2 0 0 IS O fi l m Tests at 2 0 0 an d 40 0 IS O
both sh o wed th e b ase fog an d fi l m emu l si on l i mi ted th e
ton al
r an ge .
However ,
th i s
per for med
sl i gh tl y
better
th an For te For tep an 1 0 0 IS O.
46
o
R O L L E I S H E E T F I L M 2 5 IS O to 6 4 00 IS O r ate d at 20 0 IS O.
Th e fi l m emu l si on an d base fog agai n l i mi ted th e ton al
r an ge gi vi n g si mi l ar r esu l ts to F omapan .
Fi l m b ase fog or c h e mi cal f oggi n g of com mer ci al fi l m s i s par t
of th e devel opm en t pr oce ss cau s i n g den si ty i n th e h i gh l i gh ts
an d r edu ci n g th e con tr ast of th e fi l m. Th i s fog may al so take
pl ace du r i n g poor stor age or ag ei n g. Il for d FP4 wi th th e l o west
fog base pr oved t o pr ovi de th e b est r esu l ts .
FILM D EVELOPERS TESTED
All
devel oper s
wer e
teste d
at
both
r ecomm en ded
an d
i n cr eased ti me s, var yi n g str en gth s an d temper atu r es .
PM K
DEVELOPER
Th e ox i di si n g acti o n of th e pyr ogal l ol devel o per
h ar den s th e gel ati n , cr eati n g a r el i ef on th e fi l m su r face. Th i s
l eaves a gr een / yel l o w/ br o wn s t ai n . To fu r th er th e t an n i n g
pr ocess (Hu tch i n gs, 1 9 9 2 ) su ggests pl aci n g th e n egati ve back
i n th e devel oper . Th i s h o wever fl atten ed th e ton al r an ge an d
th er efor e n ot u sed i n th e devel o pi n g pr ocess es. PM K pr ovi ded
th e best ton al r an ge to th e sal t pr i n t i n al l fi l m test s. Th e
for mu l a for th i s devel oper i s s et ou t i n A ppen di x 3 of th i s
paper .
o
AGFA RODINAL
an d
is
Th i s for m u l a dates ba ck t o 1 8 8 0 s
DEVELOPER
con si der ed
a
h i gh
defi n i t i on
devel oper
wi th
en h an ced acu tan ce an d i s acce pt ed as a good al l r ou n d
devel oper
(A n ch el l ,
2 00 0 ) .
A l th ou gh
it
per for med
r eason abl y wel l i t di d mat ch th e ton al r an ge of th e PM K .
o
P Y R O C A T -HD
DEVELOPER
Th i s
iS
Pyr ocate ch ol -ba sed
devel oper wh i ch i s sai d t o pr o du ce si mi l ar r esu l ts t o
PM K devel oper s . It pr o du ces a bl u e/ br own stai n i n s tead
of th e gr een / br own stai n l eft by PM K . Th i s pr odu ces a
l i mi ted ton al r an ge.
o
KODAK
D76
DEVELO PER
is
th e
most
co mm on l y
u sed
devel oper du e to i ts stabi l i ty a n d pr edi ctabi l i ty . Th i s
di d n ot pr ovi de an adequ ate t on al r an ge.
47
INCREASING THE TONAL RANGE POST DEVELOPMENT
Negati ve r edu cer s ar e n or mal l y u sed to r edu ce th e den si t y of
fi l m wh en over devel o ped or ove r ex posed. Th i s wa s ex pl or ed
as a way t o i n cr ease th e ton al r a n ge by r edu c i n g th e ch emi cal
fog .
o
A mmon i u m
th i osu l fat e
an d
ci tr i c
aci d.
Th i s
r edu ced
sh ado w r egi on bu t di d n ot r edu ce th e h i gh l i gh ts to th e
same degr ee .
o
K odak R -4 b: D espi te th e stateme n t th at i t r emoved th e
fog base (A n ch el l , 2 0 0 0 ) i t pr oved to r e move th e den si t y
i n th e h i gh l i gh ts a l so.
o
Far mer s R edu cer r emoved th e fog base bu t al so r emove d
th e den si ty i n th e h i gh l i gh ts .
Negati ve i n ten si fi er s ar e gen er al l y u sed to i n cr eas e th e fi l m ‟ s
den si t y wh en ei th er u n der ex pos u r e or u n der devel opmen t h a s
occu r r ed .
o
S el en i u m sol u ti on of 1 : 1 0 for 10 mi n u tes i n cr eased th e
h i gh l i gh t ‟ s
den si ty,
i n cr eas i n g
th e
ton al
r an ge
by
2
stop s wh i l e i n cr easi n g th e sh a do w r egi on t o a l e sser
degr ee .
S el en i u m wa s th e on l y s u cce ssfu l agen t to i n cr ease th e ton al
r an ge u si n g a post devel op men t p r ocess.
RESULTS OF ANALOGUE NEGATIVES TESTS
Th e combi n ati on of HP4 fi l m an d PM K devel oper pr odu ced th e
best sal t pr i n t n egati ve s . Th e n egati ve s wer e ex po sed for th e
sh ado ws , r ati n g th e fi l m at 1 00 IS O. Th e str en gth of th e
devel oper sol u ti on was dou bl e d t o i n cr ease th e fi l m den si ty.
M an y of th e n egati ve s tested app ear ed to pr ovi de a good r an ge
an d den si to meter r eadi n gs see m ed to con fi r m th i s. Ho wever
th e pr i n t test s di d n ot match th e ex pecte d r esu l ts, ex c ept f or
th e FP4 fi l m i n PM K devel oper . Ch emi cal fog seem ed to i mp ede
48
th e
i n for mati on
in
th e
h i gh l i gh t
an d
mi d -ton e
r egi on s.
A n al yses i n di cate d th at th e gr ee n / br own of th e PM K n egati ve
con tr ol s th e wa y th e UV spectr u m tr an smi ts th e l i gh t t o th e
sen si ti sed p aper , ex ten di n g th e ton al r an ge. Th e PMK stai n s
th e gel ati n base pr opor ti on al l y t o th e den si ty , th e den ser th e
r egi on th e gr eater stai n i n g. Fu r th er , th e swel l i n g or r el i ef
vi si bl e acr os s th e n eg ati ve su r face app ear s to add an ex tr a
di men si on .
Th e fol l o wi n g fi gu r es, ch ar t an d tabl es s et ou t h o w each of th e
fi l ms wer e teste d an d r ecor ded .
Fi gu r e 4 -1 A .
i s th e an al ogu e
n egati ve fi l m an d fi gu r e 4 -1 B . i s th e r esu l ti n g sal t pr i n t. Th e
Tabl e 4 -1 sets ou t th e r eadi n gs taken on th e den si tomet er
fr om th e fi l m, wh i ch ar e con ver t ed to th e Ch ar t 4 -1 . Th e same
r eadi n g
meth od
was
u sed
f or
each
fi l m
t ested
an d
th e
r esu l ti n g pr i n t . M or e th an 1 5 0 tests wer e car r i ed ou t ; th ei r
i n cl u si on was c on si der ed u n wi el dy for th e r eader . Th ese are
avai l abl e for vi ewi n g i f so r equ i r ed.
A
B
Figure 4-1 A Negative and B Salt Print
49
Film No.
Date:
Development
FP4 30
26/10/06
Pre-
Dev..Time
Dev..Temp
Dev. Type
Stain
wash
7 min
26 C
PMK 2:4:100
No
No
Steps
Cyan
Magenta
Yellow
VIS
1
0.30
0.30
0.33
0.35
2
0.60
0.63
0.68
0.65
3
0.73
0.75
0.85
0.80
4
0.76
0.78
0.89
0.83
5
0.83
0.85
0.98
0.90
6
0.94
0.96
1.11
1.01
7
0.99
1.01
1.17
1.06
8
1.05
1.07
1.24
1.12
9
1.10
1.13
1.32
1.18
10
1.19
1.21
1.42
1.26
11
1.26
1.29
1.52
1.34
12
1.34
1.37
1.62
1.42
13
1.43
1.46
1.73
1.51
14
1.52
1.55
1.85
1.60
15
1.60
1.64
1.95
1.69
16
1.70
1.73
2.05
1.78
17
1.80
1.83
2.18
1.87
18
1.99
2.03
2.41
2.07
19
2.09
2.12
2.52
2.16
1.79
1.82
2.19
1.81
Density
range
Film Exposure
Image
ISO speed
Aperture
EI
Av density
density
units
units
1.74
100 MAR
f32
1.2
1.90
Table 4-1 Film Density Readings
50
FILM No FP4 30
PMK developer 2:4:100
2.80
Density Reading
2.30
1.80
1.30
0.80
0.30
1
2
3
4
5
6
7
8
9
10 11
Steps 1/2 stops .15 density units
Cyan
Magenta
12
13
14
15
16
Yellow
17
18
19
B&W
Chart 4-1 Film Density Readings
READINGS ON A DENSIT OMETER
D en si ty i s th e measu r e of l i gh t wh i ch p asse s th r ou gh th e
n egati ve .
Th i s
is
kn own
as
tr an smi ssi on
den si t y.
L i gh t
r efl ecti n g fr om pr i n ted mat er i al i s kn o wn as r efl ec ted den si t y .
Th e den si to meter gi ves se t val u es to tr an smi tte d an d r efl ected
l i gh t . Th i s se t o f val u es al l o ws a c on si st en t co mpar i son for
both th e fi l m an d th e r esu l ti n g p r i n ts . D en si ty r an ge r efer s to
measu r i n g th e th i n n est an d th e den sest par t of th e n ega ti ve ;
th e di ffer en ce bet ween i s th e den si ty r an ge.
51
Ch ar t 4 -2 demon str ates th e di ffe r en ce th e devel o per s made on
th e fi l m an d cor r espon di n g effect on th e pr i n t.
Film Print Comparison
3
Density Range
2.5
2
1.5
1
0.5
0
PMK Developer
FP4film
FP4Print
FP5 Film
FP5 Print
Rodinal Developer
Forte Film
Forte Print
Foma film
Foma print
Chart 4-2 Film Print Comparison
ENLARGING NEGATIVES IN THE DARKR OOM
For con tact pr i n t i n g, 3 5 mm an d medi u m for mat 1 2 0 r ol l fi l ms
mu st b e en l ar ged to th e de si r ed pr i n t si z e. Th i s was ach i eved
by mean s of i n ter -n egati ve s wh i ch i s a t wo ste p pr oce ss or
r ever se pr ocessi n g , a on e st ep pr ocess . In ter -n ega ti v es ar e
cr eated by ma ki n g a po si ti ve f i l m to th e de si r ed si z e an d
con tact pr i n ti n g th e po si ti ve on to fi l m to cr eate a n egati ve .
Th ese mat er i al s wer e ex pen si ve a n d n ot r eadi l y avai l abl e .
Th e or th o fi l m an d l i th fi l m ar e h i gh con tr ast so di l u ted paper
devel oper s wer e u sed t o l o wer t h e con tr ast. A l l wer e ex p osed
an d pr ocesse d u n der a r ed safe l i gh t.
52
FIL M S TE S TE D :
o
ILFORD ORTHO PLUS
K odak S ol ectol
PM K
an d
FILM
Th e po s i ti ve was pr oc esse d i n
1 : 2. Th e n egati ve wa s pr oces sed i n both
S el ectr ol
an d
compar ed.
A l th ou gh
b oth
pr ovi ded r eason abl e ton al r an ge s th e PM K pr oved mor e
su cces sfu l . E ven so a l o ss of con t r ast was appar en t wh en
compar i n g th e or i gi n al fi l m .
o
BERGGER
ORTHOCHROMATI C
pr ocess ed
in
A gfa
B PFB –1 8
Nu etol .
The
FILM.
Th e posi ti ve was
n egati ve
test s
wer e
pr ocess ed i n both PM K an d A gfa Nu etol . Compar i son s
pr oved agai n th at th e PM K pr ovi d ed th e be tter r esu l t bu t
sti l l some l o ss of c on tr ast wa s ob ser ved .
o
MACO GENIUS
FILM
Th i s i s a ver y h i gh con tr ast fi l m so
di l u ted paper devel op er wa s u se d to l o wer th e con tr a st.
Th e posi ti v e was p r oces sed i n d i l u ted paper devel o per .
B y adju sti n g th e str en gth of th e devel oper th e con tr ast
wa s c on tr ol l ed . Th e con tr ast of t h i s fi l m c ompr e ssed th e
ton al r an ge.
o
PHOTOCHEM REVERSE
PROCESSING
Il for d Oth o Pl u s an d M aco
Gen i u s fi l m wer e t este d , n ei th e r wer e su cc essfu l . Th e
Il for d was qu i te fl at i n ton es an d th e M aco fi l m di d n ot
r espon d wel l to th e ch emi cal s , bl each i n g th e si l ver fr om
th e fi l m.
DIGITAL NEGATIVES
B on d Col ou r I magi n g, a pr ofe ssi on al ph otogr aph i c l ab or ator y ,
scan n ed th e 8 x 1 0 n egati ve at 40 0ppi gi vi n g a good qu al i ty fi l e
at
3 6 M B.
Th i s
was
u sed
as
the
con tr ol
n egati ve
for
th e
fol l o wi n g secti on of th i s r esear ch .
D i gi tal n egati ves i n cl u de In kjet n egati ves fr om di gi tal fi l es
an d
an al ogu e
n egati ves
fr om
di gi tal
fi l es.
Th ese
i n cl u de
i n kjet, i mage set ter or K odak D u r acl ear ™ pr ovi di n g bl ack an d
wh i te or c ol ou r n egati ve s. Th e c ol ou r n egati ves ar e kn o wn as
spectr al n egati ves.
53
SPECTRAL NEGATIVES
Th i s i s a ter m u sed to descr i b e fi l m wh i ch u ses col ou r to
tr an smi t or bl ock di ffer en t l i gh t wav el en gth s r each i n g l i gh t
sen si ti z ed pap er .
Th e spe ctr al n egati ve wor ks on th e sa me pr i n ci pl e. Col ou r s
con tr ol th e ton al r an ge b y th e qu al i ty an d qu an ti ty o f l i gh t
r each i n g th e l i gh t sen si ti ve paper . A l th ou gh th e col ou r dye on
fi l m can act as a den si t y , bl o cki n g l i gh t si mi l ar to si l ver
par ti cl es i n an al ogu e fi l m, i t do es n ot h ave th e sa me su btl e
ton al gr ad ati on s wh i ch tr adi ti on al an al ogu e bl ack an d wh i te
fi l m
offer s.
Th i s
is
sh o wn
to
be
mor e
pr obl emati c
in
h i gh l i gh ts an d sh ado w r egi on s.
INKJET NEGATIVES FROM DIGITAL FILES
Th er e ar e n u mer ou s appr oach es to maki n g di gi tal n egati ve s.
M ar k Nel son ‟ s P r ec i si on Di gi ta l N ega ti ves sy stem em po wer s th e
r eader
to
n egati ves
cu s tomi se
in
a
th ei r
n u mber
of
c ompu ter
ou tpu t
syst em ,
mod es
to
th at
cr eate
wi l l
su i t
par ti cu l ar pr ocess e s. U si n g r ed i n k to con tr ol th e ex p osu r e
wa s favou r ed by D an B u r kh ol der (B u r kh ol der , 19 99 ) . A l th ou gh
th er e wa s s ome su cce ss gen er al l y i t i n cr ease d th e con tr as t ,
cu r bi n g th e ton al r an ge.
It was fou n d th at pi gmen t i n ks an d dye -base d i n ks i n i n kjet
pr i n ter s
made
a
c on si der abl e
di ffer en ce
to
th e
n egati v es ‟
den si ty an d ton al r an ge. Gen er al l y dye ba sed i n k s pr odu ce a
wi d er gamu t of col ou r an d a h i g h er r esol u ti on . Th e i n k si t s i n
th e str u ctu r e of th e fi l m. Th e pi gmen t i n k si ts on th e su r face
of th e fi l m . Th e dye -base d i n ks abi l i ty to bl o ck UV l i gh t i s
gr eater
th an
th e
pi g men t
base d
i n ks
( Nel son ,
2004).
Th e
pi gmen t i n ks r equ i r ed con si der abl e adju stmen t to cr eate th e
same den s i ty an d con tr ast a s th e dye base d i n ks.
Th e type of i n kjet fi l m var i ed fr om cl ear to opaqu e. D i ffer en t
fi l m i s pr odu ced to a ccept pi g men t i n k an d dy e bas ed i n k s.
Tests wer e car r i ed ou t to sel ec t th e bes t r esu l ts. Th e dye
54
based
ink
on
A gfa
Copy
Jet
wa s
r e l ati vel y
i n ex pen si ve,
avai l abl e l ocal l y an d for tu n atel y pr ovi ded th e better r esu l ts.
o
In kjet bl ack an d wh i te n egati ve s . Th ese fai l ed t o pr ovi de
su ffi ci en t den si ty .
o
In kjet s pectr al n egati ve s . Th es e pr ovi ded th e b est of al l
th e di gi tal n egati ve s. A s th e ou t p u t was fa st an d easy on
an i n kjet pr i n ter , n u mer ou s te st s cou l d b e car r i ed ou t.
Th e
col ou r s
th at
pr ovi d e
th e
gr eatest
t on al
r an ge
ach i eved a r esu l t si mi l ar to th e su cces sfu l FP4 fi l m an d
PK M devel oper as sh o wn i n Fi gu r e 4 -2 .
o
Paper
i n kjet
n egati ves .
E ven
t h ou gh
th e
fi n e
paper
tested h ad mi n i mal tex tu r e i t affect ed th e pr i n t den si ty
an d th e paper cu r bed th e t on al r an ge wh i l e th e tex tu r e
soften ed th e i m age acu tan ce.
Figure 4-2 PMK Tones in Digital Negatives
In an al ogu e pr i n ti n g th e emu l si on si de of th e fi l m i s pl aced on
th e l i gh t sen si ti sed si de of th e p aper . Th i s r u l e sti l l ap pl i e s i n
i n kjet n egati ves .
55
ANALOGUE NEGATIVES FROM DIGITAL FILES
D i gi tal fi l es wer e cr eated fr om t h e scan n ed con tr ol n egati ve.
B oth of th e fol l o wi n g n egati ve s wer e cr eat ed by ex p osi n g th e
di gi tal fi l e by l aser on to l i gh t sen si ti ve mater i al . Th i s mater i al
wa s th en pr oces sed b y de vel opi n g i n a tr adi ti on al " wet" fi l m
pr ocess or .
o
KODAK DURACLEAR™
SPECTR AL NEGATIVE.
Th i s col ou r fi l m i s
man u factu r ed for adver ti si n g l i g h t box es. Its cl ear fi l m
base made i t su i tabl e f or spec tr al n egati ves. V ar i ou s
tests wer e car r i ed ou t u si n g di f fer en t col ou r s . Th e i n bu i l t
UV
pr otecti on
con si der abl y
r eason abl y
in
a
sl o we d
UV
l i gh t
su cces sfu l
in
th e
box .
ex posu r e
H owe ver
pr odu ci n g
th e
ti mes
th i s
ton al
wa s
r an ge
u si n g su n l i gh t . Th i s i mpr oved th e ex posu r e ti me s o wi n g
to
th e
tr an smi s si on
of
l i gh t - wa ves
in
th e
vi si bl e
spectr u m. Th i s i s i l l u str ated i n Ch ar t 4 -3 . Th i s fi l m i s
qu i te
ex pen si ve ,
h o wever
B on d
Col ou r
I magi n g
L ab
su bsi di se d th e cost f or th i s r esear ch .
o
IMAGE
SETTER FILM FRO M THE SCANNED NEGATIVE.
Th i s ou tpu t i s
bl ack an d wh i te an d th e c ost of th i s fi l m i s r eason abl e.
Nu mer ou s te sts wer e car r i ed o u t an d th e var i ou s d ot
scr een s, sp ot ty pes an d an gl es cr eated var yi n g col ou r s
wi th th e sal t pr i n t. Th e ou tcome fr om th e pr i n ts was n ot
as pr omi si n g as
aban don ed.
oth er
H o wever
it
meth o d s
di d
an d th e testi n g
r ai se
qu es ti on s
wh y
wa s
th e
space an d an gl e s of th e dots a ff ected th e c ol ou r of th e
pr i n ts test ed.
56
Figure 4-3 Spectral Negatives
Th e
di ffer en t
spectr al
col ou r
n egati ves
tests
wi th
du r i n g
th e
ou tpu t
th e
on
ex pl or ati on
i n kjet
of
an d
th e
K odak
D u r a cl ear ™ fi l m ar e demon str ated i n Fi gu r e 4 -3 . In th e top
r i gh t cor n er th e di ffer en t squ ar es of col ou r assi st ed i n fi n d i n g
th e col ou r s th at wou l d pr ovi de th e max i mu m an d mi n i mu m
den si ty i n th e pr i n t.
Ch ar t 4 -3 i l l u str ates th e tr an s mi s si on of a n u mber of th e fi l m s
tested. Th e r eadi n gs wer e ta ken on th e cl ear par t of th e fi l m
wi th ex cep ti on of „F P4 S i l ver Tr an smi ssi on %‟ . Th i s was ta ken
in
th e
D -max
of
th e
si l ver .
Th e
r esu l ti n g
sampl es
wer e
57
acqu i r ed
u si n g
a
Car y
50
UV
S pectr oph oto meter
at
th e
Ul tr avi ol et R adi ati on S ecti on of A R PA NS A .
Film Transmission
100
90
80
Transmission %
70
60
50
40
30
20
10
750
650
550
450
430
410
390
370
350
330
315
300
200
0
Wavelength
FP4 Silver
FP4 Clear
Kodak Durotrans™
Agfa CopyJet
Pictorico %
Imagesetter %
Lith %
Chart 4-3 Film Transmission
In vesti gat i n g th e t on e r epr odu cti on of th e sal t pr i n t wa s ti me
con su mi n g. E ach n egati ve type wa s fou n d to h ave n u mer ou s
var i ati on s an d pr obl e ms. Th e t i me sp en t on th e n egati ve,
58
especi al l y th e di gi tal as pect , be came di s pr opor ti on ate t o th e
en ti r ety of th i s r esear ch paper . A l th ou gh a gr eat deal mor e
ex pl or ati on cou l d be car r i ed ou t, th e r esu l ts at th i s poi n t wer e
fel t to be r eason abl y con cl u si ve.
Th e fi l m n egati ve offer s th e gr eatest ton al r an ge, pr ovi di n g
su btl eti es o f ton e s th at th e di gi ta l n egati ve cou l d n ot pr odu ce.
Th e con jec tu r e was d ots maki n g u p th e i n kjet n egati ve ar e at
on e l evel bu t th e si l ver an al ogu e n egati ve pr ovi des a gr adati on
of ton es . A ddi ti on al l y , a r el i ef o f di ffer en t l evel s i n th e fi l m
emu l si on o ffer s fu r th er di men si o n s. PM K devel oper f or m ed th e
gr eatest r el i ef i n th e fi l m emu l si on .
Th e su cc essfu l sal ted pap er pr i n t r equ i r es a n egati ve wi th a
l on g ton al
r an ge
an d su ffi ci ent
den si ty
for
en ou gh
si l ver
ch l or i de to ch an ge i n to i mage maki n g metal l i c si l ver du r i n g
ex posu r e . E x ten si ve testi n g pr oved th at Il for d FP4 n egati ves
pr ocess ed i n th e dou bl e str en gt h PM K devel oper pr ovi de d an
ex cel l en t con ti n u ou s ton e , an d pr odu ced th e ex tr a den si ty
desi r abl e for sal t pr i n t i n g.
Th e i n kjet n egati ve s wi th s i mi l ar
col ou r s to th e FP4 / PM K n egati ve pr oved to su r pas s a n u mber
of oth er types of an al ogu e fi l m n egati ves tes ted.
Negati ve s wi th i n adequ ate ton al r an ges an d den si ty f ai l e d to
pr odu ce qu al i ty sal t pr i n t s.
Hi gh con tr ast n egati ves ar e often qu oted i n tex t (James, 2 0 0 2 )
(Webb
an d
R eed,
2000)
as
a
basi c
r equ i r emen t
for
th e
su cces sfu l sal t pr i n t. A l o w con t r ast n egati ve pr odu ce s a fl at
pr i n t bu t h i gh con tr ast n egati v e s r esu l t ed i n h ar sh „con tr ast y ‟
pr i n ts l osi n g detai l i n th e sh a do ws an d / or th e h i gh l i gh ts. Th e
l on g ton al r an ge of sal t pr i n ts pr ovi des ex cepti on al separ ati on
i n th e h i gh l i gh ts an d r ec or ds mi d ton e s par ti cu l ar l y wel l .
Ho wever s h ado ws l ack th e sa me degr ee of separ ati on an d may
l ack det ai l . A n egati ve wi th a h i gh per cen tage of sh a do w ar ea
cau se s an i mage to a ppear fl at , s o ex po si n g for th e sh ado ws i s
cr i ti cal . Th i s i s wh en th e sal t pr i n ts sel f -mas ki n g abi l i ty can
be u ti l i sed to max i mi s e th e ton al r an ge.
59
Chapter 5 EXPOSING
THE PRINT
A cti n i c i s th e l i gh t th at cau se s ch emi cal s to co mbi n e an d
decom pos e . S al t pr i n ts r el y on th i s en er gy as i t i s r i ch i n u l tr a
vi ol et an d bl u e r ays to cr eat e a ch emi cal r eacti on . Th e su n or
i ts al ter n ati ves (l a mp s or tu be s th at emi t UV l i gh t ) pr ovi de
th i s en er gy .
Wh i l e ex posi n g n egati ve s on th e sen si ti z ed paper , th e i mage
can be obser ved as i t appear s. Th i s ch apter i n vesti gates h o w
th e col ou r an d c on tr ast of th e pr i n t ar e affected by ex p osu r e.
Th er e ar e con tr ol s over th e i nten si ty of th e l i gh t an d th e
l en gth of ex posu r e wh i ch affe ct th e col ou r an d den si ty of th e
fi n al pr i n t.
Th e UV l i gh t affect s th e si l ver ch l or i de r el easi n g ver y s mal l
si l ver par ti cl es . Wh en si l v er i s i n ex cess, th e si l ver h al i de
car r i es th e ex ces s si l ver i on s abs or bed on to th e paper su r face
(War e, 1 99 4 ) .
Th e fol l o wi n g var i abl es wer e ex pl or ed .
o
V ar yi n g
l evel s
of
UV
an d
visi bl e
l i gh t ,
an d
the
di ffer en ces th ey ma y gen er ate .
o
Ti me of th e day an d t i me of th e y ear .
o
Hu mi di ty an d ambi en t t emper atu r e .
o
D i r ect su n l i gh t (cr eates l ess con t r ast as th e ex po su r e i s
faster ).
o
In di r ect su n l i gh t an d cl ou d cove r ( i n cr eases c on tr ast a s
th e ex posu r e i s sl o wer ) .
SILVER CHLORIDE SENSITIVITY TO UV AND VISIBLE SPECTRUM
It
wa s
establ i sh ed
ex posu r e
fr ames
th r ou gh
bl o cked
tes ti n g
100%
of
th e
wave
gl ass
u sed
l en gth s
in
the
fr o m
330
n an ometr es an d bel o w. T h e l i gh t th at i s of i n ter est f or th e sal t
60
pr i n t i s fr om 3 3 0 n m i n th e u l tr a vi ol et r egi on an d vi si bl e l i gh t
u p to 6 5 0 n m.
A l an
E l l i ot
i n vesti gat ed
ex per i men t
advi sed
A l th ou gh
emai l
th e
spec tr al
wi th
a smal l
dagu er r eotype
sen si ti vi ty
by
of
pl ate
si l ver
sen si ti vi ty
29th
of
sen si ti vi ty
n eon
s en si ti sed
ver y
of
l aser
low
2007
si l ver
at
wi th
i odi de ex t en ded
wa s
M ar c h
to
at
at
th at
h ad
i odi de .
650
i odi n e
he
An
n m an d
sh o wed
l east
650
a
th e
n m.
wavel en gth
it
defi n i tel y wa s n ot z er o. Th i s en cou r aged th e i n ves ti gati on of
si l ver ch l or i de ‟ s sen si ti vi t y u p to th e 6 5 0n m r egi on .
D u r i n g th e mi d par t of th e day th e su n i s i n a mor e dir ect l i n e
to th e ear th an d th er efor e th e r e i s mor e UV pen etr ati on .
Testi n g for th e var i ou s sp ectr u m cu t- ou t fi l ter s t ook pl ace
bet ween 1 2 . 0 0 h ou r s an d 1 4 . 3 0 hou r s at D e -i on i si n g R adi ati on
B r an ch of th e A u str al i an R adi ati on Pr otecti on an d Nu cl ear
S afety A gen cy . Th e fi l ter s teste d r an ge d fr om 3 0 5 n m to 6 4 5n m
as sh o wn i n Ch ar t 5 -2 .
Figure 5-1 Cut- off Filter Tests
61
Silver Chloride Sensitivity
1.80
1.60
1.40
Density
1.20
1.00
0.80
0.60
0.40
0.20
Control
WG305
WG320
WG345
WG360
GG375
GG385
GG395
GG400
GG420
GG435
GG455
GG495
OG530
OG570
OG610
OG645
Paper Base
0.00
Cutoff Filters
NaCl
NH4Cl + GEL +Sodiun citrate
Albumen
Formulas
NaCl + Gel
Arrowroot
Chart 5-1 Silver Chloride Sensitivity
Cut-Off Filters
100.00
90.00
80.00
Transmission (%)
70.00
60.00
50.00
40.00
30.00
20.00
10.00
0.00
200
WG305
GG400
400
WG320
GG420
600
Wave length
WG345
GG435
WG360
GG455
800
GG385
GG495
1000
GG395
OG530
Chart 5-2 Cut-off Filters
62
Th e test i n di cated pe ak sen si ti v i ty of si l ver ch l or i de i s fr om
3 6 0 n m to 3 8 5n m. Ho wever as sh o wn i n Ch ar t 5 -1 an d Fi gu r e 5 1 th er e i s sti l l str on g sen si ti vi ty u n der 3 6 0 n m. A bove 3 85 n m
sh o ws a gr adu al decl i n e an d at 4 5 5 n m th e sen si ti vi ty dr ops
r api dl y. S u bstan ti al l y wea ker acti vi ty i s appar en t to 6 4 5 n m.
Th e
cu t
of f
fi l ter s
avai l abl e
at
th e
D e-i on i si n g
R adi ati on
B r an ch of th e A u str al i an R adi ati on Pr otec ti on an d Nu cl ear
S afety A gen cy st oppe d at 6 5 0 n m, h owever , an assu mp ti on th at
sen si ti vi ty c ou l d ex ten d beyon d 6 5 0 n m wou l d be r eason abl e .
Th e tests c on cl u ded th e gr eates t effect of l i gh t on th e sal t
pr i n t peaks at abou t 3 8 0 n m (n an ometr es) de pen di n g on th e
for mu l a an d bi n der , bu t vi si bl e l i gh t u p to 6 5 0 n m wi l l r edu ce
si l ver ch l or i de to metal l i c si l ver . S en si ti v i ty at th e h i gh er en d
of th e spec tr u m i s ver y l o w bu t some a cti vi ty of th e si l ver
ch l or i de i s sti l l appar en t .
Th e ambi en t tem per atu r e a ffect s sen si ti vi ty of th e ex posi n g
pr i n t wi th mu ch sl o wer r edu c ti o n of si l ver t aki n g pl ac e b el o w
5 ° C. Hi gh er temper atu r es al so cr eate h u mi di ty a s th e m oi stu r e
i s r el eased fr om th e pap er , i n cr easi n g th e sen si ti vi ty of th e
si l ver
ch l or i de.
bi n der s
o wi n g
Th i s
to
th e
wa s
mor e
am mon i a
n oti ceabl e
con ten t
wi th
ar r owr o ot
r e spon di n g
mor e
r api dl y as th e h u mi di ty i n cr eases .
D i ffer en t types of n egati ves h ave di ffer en t UV an d vi si bl e
l i gh t
spectr u m
di ffer en t
fi l m
tr an smi s si on s.
emu l si on s,
appl i ed to fi l m.
Th i s
is
deve l oper s,
at tr i bu tabl e
base
f og
to
an d
th e
i n ks
Th e K odak D ur a cl ear ™ an d th e FP4 i n PMK
devel oper sh o wn i n Ch ar t 5 -3 ar e a good ex ampl e of th i s
di ffer en ce. A l so sh o wn i n Ch ar t 5 -3 th e FP4 an d th e A gfa Copy
Jet h ave si mi l ar tr an smi ssi on pr oper ti es th r ou gh th e fi l m D mi n base. A s si l ver or dye i s appl i ed th e tr an smi ssi on wi l l
ch an ge
accor di n g
to
th e
c ol o u r
an d
den si ty.
Ch ar t
5 -3
compar e s FP4 D -mi n an d FP4 D -max i n di cates th e di ffer en ce i n
63
th e % of l i gh t tr an smi tted fr om t h e cl ear to th e den sest par t of
th e fi l m.
(NB : Ch ar t 5 -3 i s si mi l ar to Ch ar t 4 -3 , th e data i s
r eu sed for easi er compar i s on i n th i s ch apter ).
.
Film Transmission
100
90
80
Transmission %
70
60
50
40
30
20
10
FP4 PMK D-max
FP4 PMK D-min
Kodak Duraclear D-min
Agfa Copy Jet D-min
750
650
550
450
Wavelength
430
410
390
370
350
330
315
300
200
0
Chart 5-3 Film Transmission
Th e i n ten si ty of acti n i c l i gh t vari es wi th th e ti me of year an d
th e ti me of da y. A s th e an gl e of t h e su n to th e ear th i n cr ease s
th e con tr ast of th e pr i n t al so i n cr eases. D u r i n g th e wi n ter
mon t h s th e pr i n t ex p osu r e i s mor e gr adu al be cau se of th e
an gl e of th e su n an d th e l o wer ambi en t te mper atu r e s. Tu r n i n g
th e ex posi n g pr i n t awa y fr om th e su n i n cr ease s th e con tr ast.
A n ex posu r e fr ame, or con tact pri n t fr ame , i s made u p fr om 3
par ts; th e fr ame, g l ass an d a r emovabl e h i n ged back. Th e
fr ame h ol ds th e gl as s i n pl ace an d th e h i n ged bac k ap pl i es
pr essu r e
on
th e
pa per
an d
n egati ve
to
s top
mo vemen t,
en su r i n g th ey r emai n i n r egi s tr ati on . Th e fi l m e mu l si on i s
64
pl aced agai n st th e sen si ti se d pap er emu l si on . Th e h i n ged back
al l ows i n spect i on of each si de o f th e pr i n t wi th l i ttl e r i sk of
der egi ster i n g th e fi l m an d paper .
Wh en
th e
ex posu r e
fr ame
is
pl aced
in
th e
su n l i gh t,
th e
di ffer en ce i n temper atu r es bet we en th e cool gl as s an d th e
en cased sen si ti z ed pa per cr eat es a h u mi di t y ch a mber wi th i n a
fe w sec on ds . Th i s i n cr eases th e sen si ti vi ty of th e p aper an d
th e i mages app ear war m er i n col ou r .
EXPOSURE TIMES
Ju dgi n g th e r i gh t ex posu r e i s di f fi cu l t . Th e pr i n t mu st be over
ex posed b y abou t t wo stop s . F i x e r r emoves abou t t wo to th r ee
stop s of den si ty, bu t as th e i ma ge dr i es i t r egai n s on e to t wo
stop s i n den si ty. It i s t h e amou n t of si l ver ch l or i de con ver ted
to metal l i c si l ver ma kes th e den s i ty i n th e i mage.
Li g ht S o ur c e
T i me
UV l i gh t box
1 5 to 3 0 mi n u tes
D i r ect s u n (n oon )
1 0 to 2 0 mi n u tes
In di r ect su n (du l l day )
3 0 mi n u tes to 3 h ou r s
Table 5-1 Exposure Times
In tabl e 5 -1 th e UV l i gh t box ex po su r e i s b ase d on a ban k of 1 7
Ph i l i ps A cti n i c B L 40 watt mer cu r y vapou r fl u or e scen ce UV
tu bes at a di stan c e of 2 0 cm fr o m th e pr i n t. Th ese t u bes e mi t
UV A fr om 4 0 0 to 3 2 0 n m pe aki n g r ou n d 3 7 0 to 3 8 0 n m . Th i s i s
sh o wn
in
fl u or escen t
Ch ar t
tu bes
5 -4
u se d
wi th
a
in
th e
compar i son
wor k
r oom.
of
UV
Osr am
fi l ter s
880
for
fl or escen t tu be s i n di ca ted l i t tl e e ffect a s l i gh t bel o w 4 0 0 n m i s
n ot emi tted .
65
Fluorescent Tube Wavelength Frequency
800
690
660
630
600
570
540
510
480
450
420
390
360
330
290
260
230
200
λ
4200
4000
3800
3600
3400
3200
3000
2800
2600
2400
2200
2000
1800
1600
1400
1200
1000
800
600
400
200
0
Wavelengths
Osram880
Osram 880 with UV Filter
Philips - 40W
Chart 5-4 UV Tube Wavelenghts
B y com par i n g C h ar t 5 -1 , Ch ar t 5 -2 an d Ch ar t 5 -3 th e si l ver
ch l or i de pr i n t ex posed i n th e U V l i gh t box on l y r ecei ves th e
wa ves of pea k sen si ti vi t y an d t h i s mean s th e n egati ves ar e
on l y tr an smi tti n g a smal l por ti on of th e possi bl e spectr u m .
Th e ex posu r e ti mes ar e de pen den t on a n u mber of var i abl es:
1 . Negati ve den si t y an d fi l m type .
2 . B i n der type ( ar r owr oot i s fast er th an al bu men du e to th e
accel er ati n g effect of a mmon i a i n th e sol u ti on ) .
3 . A ddi ti ves (pota ssi u m di ch r omat e wi l l i n cr ease
ti me, sodi u m ci tr ate decr ease s ex posu r e ti me ).
ex po su r e
4 . M eth od of ex posu r e (su n l i gh t or con tr ol l ed UV l i gh t box )
66
Tr an smi ssi on S tep wedge s
Tr an smi ssi on ste p wedge s as si s t ed ton al r an ge co mpar i son s
agai n st n egati ves. B y ex posi n g th e step wedge besi de th e
n egati ve h el p ed t o i n di cate th e ton al r an ge i n th e ex pos ed
pr i n t, th u s assi st i n g i n cal cu l ati n g fu tu r e ex posu r es. Th e step
we dge wa s tr eated a s fu l l y ex po s ed wh en th e fi r st st ep wa s th e
same col ou r as th e ex p osed pap er ou tsi de th e n egati ve ar ea.
Th i s
wa s
ju s t
bef or e
br on z i n g
occu r r ed.
Th i s
h el p ed
to
deter mi n e :
o
Th e
ton al
scal e
of
th e
ex po sed
paper .
Th i s
wa s
i n di cated by th e n u mber of se par ate step s vi si bl e.
o
If th e n egati v e h a d th e sa me to n al scal es as th e st ep
we dge.
Tests wer e ma de u si n g th e var i o u s n atu r al den si ty fi l ter s. A s
th ese sl o w th e ex po su r e ti mes i t wa s ex pecte d th at an i n cr ease
of con tr ast wou l d be th e r esu l t. Th i s di d n ot occu r . R esear ch
establ i sh ed some n eu tr al den si ty sh eet fi l m u s ed dye s to
absor b th e l i gh t an d s ome gl ass fi l ter s i n cl u de d car bon wh i ch
al so fi l ter s di ffer en t wav e l en gth s bu t on l y i n th e vi si bl e l i gh t
spectr u m.
RECIPROCITY FAILURE
S l ower ex po su r e s i n cr ease th e co n tr ast of th e i mage wh i l e fast
ex posu r es d ecr ease th e con tr as t . Th e ex tr emes of ei th er of
th ese wi l l cau se r eci pr oci ty fai l u r e.
Hi gh i n ten si ty r eci pr oci ty fai l u re can occu r i f th e i mage i s
ex posed di r ectl y to h i gh UV co n ten t i n br i gh t su n l i gh t. Th e
ph oto l ysi s acti vi ty decr ease s an d th e sh ado ws wi l l n ot pr i n t as
dar k as l on ger ex posu r es . Th e l oss of th e dar kn ess i n th e
sh ado ws fl atten s th e ton al r an ge an d decr eases th e c on tr ast.
.
67
SELF MASKING
Th e sal t pr i n t „sel f - mask s‟ as i t i s ex posed to l i gh t . Th e
r edu ced me tal l i c si l ver bl o cks l i gh t to th e u n ex posed si l ver
bel o w. Th e sh ado w r egi on ( th e mor e tr an spar en t par t of th e
n egati ve)
sl o ws
th e
r edu c ti o n
of
si l ver . Th e pr i n ts l i gh ter ar eas (th e
den se par t of th e n ega ti ve) c on ti n u e
to ex po se n or mal l y. It i s t h i s sel f maski n g th at pr odu ces th e ex te n ded
ton al
r an ge
of
th e
sal t
pr i n ts
(Cr awf or d , 1 9 7 9 ) . Th i s i s i l l u strated
i n fi gu r e 5 -2
Figure 5-2 Self Masking
BRONZING
B r on z i n g mean s th e par ti cl es of r edu ced metal l i c si l ver h ave
mi gr ated to th e su r face for mi n g a l ayer on th e su r face of th e
pr i n t. Th i s i s th e satu r ati on p oi n t wh er e th e pr i n t i s ov er
ex posed . D u r i n g ex posu r e th i s b r on z e gr een i sh br assy br o wn
sh een appe ar s on pr i n ts (R ei l l y, 1 9 80 ) . V er y l i gh t br on z i n g i n
th e i mage di sap pear ed du r i n g pr ocessi n g.
Fi gu r e
5 -3
i l lu str ates
at
di ffer en t
mag n i fi cati on s
how
si l ver par ti cl e s h ave mi gr ated t o th e su r face. Th e 1
st
th e
i mage
sh o ws magn i fi cati on at 2 3 1 ti me s l i fe si z e , th e 2 n d i s at 1 3 5 1
ti mes l i fe si z e an d th e 3 r d at 3 6 1 ,1 8 0 ti mes l i fe si z e .
Figure 5-3 Bronzing Surface Detail
68
Paper fi br e str u ctu r e i s n or mal l y vi si bl e bu t wi th br on z i n g i t
appear s smo oth u n ti l th e h i gh er magn i fi cati on r ev eal s th e
si l ver par ti cl es th at h ave been r ai sed to th e su r face .
Figure 5-4 Bronzing high Magnification
Fi gu r e 5 -4 magn i fi cati on at 1 0 1 , 69 1 ti mes l i fe si z e, i l l u str ates
th e var yi n g par ti cl e si z es fr om 2 0 n m to 1 5 1 n m. Th ese ar e
measu r ed on th e scr een du r i n g th e n an oS E M scan n i n g pr ocess.
Con ti n u i n g
th e
ex posu r e
cr eate s
a
deep
br on z i n g
wh i ch
r emai n s i n th e i mage sh ado w r egi on s after pr oces si n g . Th i s
destr oy s th e pr i n t s sh ado w ton es . If a n egati v e h as c or r ect
den si ty an d b r on z i n g h as for m e d i n th e mar gi n s , th e pr i n t is
at
i ts
max i mu m
mon i tor ed
by
den si ty.
vi e wi n g
Th i s
mar gi n s
mean s
ou tsi de
ex po su r e
th e
can
n egati ve
be
ar ea
wi th ou t open i n g th e ex posu r e fr ame .
Wh en th e pr i n t i s ex posed to l i gh t :
o
Th e
si l ver
ch l or i de
di sa ss oci at es
th e
si l ver
an d
th e
ch l or i de, r el easi n g smal l par ti cl es of si l ver metal .
o
S i mu l tan eou sl y fr ee ch l or i n e mol ecu l es ar e r el eased.
o
Th e ch l or i n e absor ber s , compr i si n g of moi stu r e of th e
paper fi br es an d ex ce ss si l ver n i tr ate , r eact wi th th e
r el eased ch l or i n e for mi n g mor e s i l ver ch l or i de.
69
o
Th e l i gh t con ti n u es to br eak do wn th i s n e w si l ver
ch l or i de cr eati n g mor e metal l i c si l ver , an d th e cycl e
con ti n u es (War e, 1 9 9 4 ).
Wi th ou t l i gh t, spon tan e ou s r edu c ti on of me tal l i c si l ver cr eate s
a yel l ow c ol ou r . Th i s con si sts o f r edu ced metal l i c si l ver i n a
fi n el y
di vi ded
state
(sl o w
ex p osu r es
i n cr ease
con tr ast
by
cr eati n g fi n er si l ver ) , accel er ated by war m th an d h u mi di ty
(R ei l l y, 19 8 0 ). Wh en th e r edu cti on of si l ver co n ti n u ed th e
col ou r ch an ge d to r ed br o wn a n d after a per i od of mon th s ,
actu al l y h a d a br on z ed appear an ce .
Ti n y
si l ver
par ti cl e s
c ombi n e
for mi n g
l ar ger
par ti cl es
ch emi st s cal l col l oi dal . Th ey ab s or b so me wavel en gth s bu t ar e
n ot l ar ge en ou gh to absor b a l l wa vel en gth s of l i gh t. Th i s i s
depen dan t on th e i n dex o f r efr acti on of th e bi n der i n wh i ch
th ey ar e di sper sed. For ex am p l e , al bu men h as a di ffer en t
r efr acti on to gel ati n cr eati n g a di ffer en t col ou r .
Th e sen si ti vi ty of th e si l ver ch l or i de to th e vi si bl e s pectr u m
pr oved to be far m or e wi de -r an gi n g th an ex pected . Th e UV
l i gh t
box
fl u or escen ce
Ph i l i ps
A cti n i c
mi r r or ed
th e
BL
pea k
40
watt
mer cu r y
sen si ti vi t y
to
vapou r
th e
sol ar
spectr u m. Th i s ex pl ai n s th e po or ou tcome fr om fi l m wi th a
h i gh base fog or i n bu i l t UV fi l te r s su ch as K od ak D u r ocl ear ™
as i n su ffi ci en t l i gh t was tr an sm i tted at th e si l ver ch l or i des
peak
sen si ti vi ty.
Ho wever
s u n l i gh t
ex posu r es
pr ovi d ed
en ou gh r adi ati on fr om th e vi si bl e spectr u m to cr eate i mages,
al th ou gh th e ex po su r es wer e 3 t o 5 ti me s l on ger wi th K oda k
D u r ocl ear ™.
Fi n di n g
h ow
th e
l on ger
l i gh t - waves
in
th e
spectr u m s pl ay a par t i n ex ten di n g th e ton al r an ge an d c ol ou r s
cal l s for possi bl e fu r th er r esear ch .
70
Chapter 6 PROCESSING
THE PRINT
Th e wash , t on i n g, fi x er an d fi n al wash i n g h a ve an effec t on
th e col ou r an d th e l i fe of th e pr i n t. A ccou n ts of t h e di ffer en t
ar eas
of
pr oces si n g
statem en ts.
Ti me
was
con t ai n
spen t
a
n u mber
te sti n g
an d
of
con fl i c ti n g
ch ecki n g
r esou r ces to fi n d some accu r acy an d con si st en cy.
var i ou s
M i ke War e,
(emai l 2 8 t h Ju n e 2 0 04 ) i n di cate d th e effect of th e 'Hyp o' fi x i n g
bath i s pr ofou n d i n modi fyi n g t h e col ou r of th e si l ver i mage .
He bel i eve d th i s i s mor e i mp or tan t th an th e par ti cl e si z e an d
su spect s i t ma y be du e to a mo n ol ayer (or mor e) o f su l ph i de
deposi t ed on th e su r face of th e si l ver n an o - par ti cl es, wh i ch
str on gl y mo di fi es th e ' su r face pl asma r es on an ce' effec ti n g th e
col ou r . He bel i eve s th i s „ su l ph i de ton i n g' i s r esp on si bl e for
mu ch
of
th e
col ou r
ph en ome n a .
As
a
r esu l t
of
War e‟ s
statem en t a stu dy of r esi du al su l ph u r was i n cl u de d i n th e
an al ysi s.
FIRST WASH
Th e
fi r st
wa sh
is
desi gn ed
to
r emove
ex ces s
s al ts
of
u n ex posed si l ver ch l or i de an d si l ver n i tr ate. Th er e ar e man y
di scr epan ci es i n th i s ar ea . On e of th e r ecommen da ti on s i s to
pl ace th e pr i n ts i n a 5 % sol u ti on of so di u m ch l or i de an d
agi tate for 2 mi n u tes (Wal l and Jor dan , 1 97 5 ) . Ter r y K i n g
su ggests wash i n g i n pl ai n water f or two mi n u tes or u n ti l water
i s cl ear (B ar n i er , 20 0 0 ) . „„Wash f or sever al mi n u tes u n ti l . . . n o
fu r th er mi l ki n ess ” (Far ber , 19 9 8) . Ch r i stoph er James (Ja mes,
2 0 02 ) su ggests a sodi u m ch l or i d e bath for 3 0 secon d s an d a
fu r th er 2 0 mi n u tes of wa sh . No t wo bo ok s see m to co n cu r .
Th e
E n cycl o paedi a
of
Ph otogr a ph y
(J on es,
1974)
(or i gi n al
pu bl i cati on 1 8 7 9 ) su ggests a we ak s ol u ti on of sal t befor e
ton i n g to r emove si l ver sal t s.
71
M i ke War e ‟ s co mmu n i cati on by emai l ( 2 2 n d Febr u ar y 2 0 0 5 )
ex pl ai n ed
th e
ph en o men a
of
this
sal t
ba th .
“ It
pr even t s
stai n i n g i n th e fi x er . Th e di l u te sodi u m ch l or i de s ol u t i on wi l l
n ot di ssol ve th e si l ver sal t s as th e sodi u m th i osu l fate d oes.
S ol u bl e si l ver i on s ar e fr o m ex ce ss si l ver n i tr ate i n sal t pr i n ts .
Th ese ar e ox i di si n g an d t en d to r eact wi th 'h ypo' u l ti matel y
cr eati n g si l ver su l ph i de . Th i s ca n cau se a yel l o w/ br o wn s tai n .
B efor e fi x i n g a sal t pr i n t wi th th i osu l ph ate i t i s i mpor tan t to
r emove th e fr ee sol u bl e si l ver i o n s . S odi u m ch l or i de does th i s
by pr eci pi tati n g si l ver ch l or i de , wh i ch i s n ot ox i di si n g . It th en
di ssol ve s
in
th e
th i osu l ph at e
fi x er
wi th
no
su l ph i de
for mati on . ”
A n u mber of test s wer e con du ct ed an d i t was fou n d th at th e
i n cl u si on of sodi u m ch l or i de i n th e ser i es of th e fi r st wash es
el i mi n ated st ai n i n g. D u r i n g th e pr ocess c ol ou r ch an ges wer e
obser ved, t h e sal t s ol u ti on „bl e ach e d‟ th e pr i n t fr om a r i ch
deep br o wn t o a l i gh t or an ge / br o wn col ou r . Th ese wer e si mi l ar
to th e fi x i n g pr ocess ch an ges.
E x cess si l ver n i tr ate, si l ver ch l or ide an d sodi u m n i tr ate r etar d
th e ton i n g pr ocess; th i s fi r st bat h ser i es i n cl u di n g th e sodi u m
ch l or i de en su r ed th ei r r emoval . Th e te mper atu r e of th e water
wa s mai n tai n ed at 2 0 ° C to i n cr eas e th e speed of th e
di ssi pati on o f ex cess sal ts. Th e p r i n t a t 3 0° C i n th i s wash
dr i ed sl i gh tl y cool er i n col ou r .
TONING
Ton i n g wi th gol d , pl ati n u m an d pal l adi u m n ot on l y i n ten si fi e s
th e i mage bu t al s o i n cr ease s th e l i fe s pan of th e pr i n t. Th e
mass of mi n u scu l e si l ver par ti cl es on th e paper su r face ar e
su scepti bl e
to
d estr u cti on
in
ox i di z i n g
an d
su l ph ur i c
con di ti on s of a n or mal atmos ph e r e . Th e gol d sh i el d s th e si l ver
par ti cl es fr om ox i di z ati on for mi n g a comp ou n d th at i s mor e
r esi stan t to ox i di z ati on (War e, 2 0 06 . ) . Th e ton er s cr eate a
l i gh t sen si ti v e ch l or i de as a b y pr odu ct of t on i n g , th i s i s
r esol ved by fi x i n g after th e ton i n g (R ei l l y, 1 98 0 ) .
72
M u ch of th e cur r en t tex t on t on i n g pr esen ts con tr adi ctor y
i n for mati on an d i n c on si st en t fo r mu l as. R esear ch an d test i n g
ton i n g
for mu l as
easi l y
sol ved
man y
of
th ese
pr obl ems.
Tex tbook s al so di ffer on th e impor tan ce of ton i n g (B ar n i er ,
2 0 00 ) h as n o men ti on of t on i n g , wh er eas (R ei l l y, 1 9 8 0 ) an d
(War e, 2 00 6 . ) di scu ss i n -depth t h e vi tal i mpor tan ce of ton i n g
sal t
pr i n ts.
Th e
for mu l as
for
th e
ton er s
ar e
se t
ou t
in
A ppen di x 2 .
Th e ter ms su ch as “ don e by i n sp ecti on ” (R ei l l y, 1 9 8 0 ) “ ton e to
th e
desi r ed
col ou r , ”
or
“ wh en
th e
pr i n t
ch an ged
to
your
sati sfacti on ” (Webb an d R eed, 2 0 00 ) ar e u sed to state th e
col ou r ch an ges du r i n g ton i n g . It i s i mpos si bl e to de tect th e
fi n al col ou r du r i n g ton i n g as man y ch an ge s i n col ou r take
pl ace befor e th e sal t pr i n t i s fi n a l l y dr y. Un l es s r i gor ou s te sts
h ave been car r i ed ou t n oti n g t y pe, str en gth an d ti me i n th e
ton e r , i t can be di ffi cu l t to r ep l i cate th e ton ed col ou r .
Th e type of bi n der an d th e pr i n t su r face make a di ffer en ce
wh en ton i n g. M an y of th e tex ts s u ggest th at al bu men r equ i r es
dou bl e th e amou n t of g ol d ch l or i de i n th e gol d ton i n g sol u ti on
(R ei l l y, 1 98 0 , Far ber , 19 98 ) . Thi s was fou n d to yel l o w th e
h i gh l i gh ts
as
i l l u str ated
in
Fi g u r e
6 -1 4 .
Ton er s
for
sal t
pr i n ti n g pr oved to be adequ ate for al bu men pr i n ti n g , an d i f
n ecessar y ex ten d i n g ton i n g ti me .
Ton i n g for mu l as asses sed i n cl u ded gol d bor ax , gol d sodi u m
acetate, t wo str en gth s of th i oc yan ate gol d t on er s, p l ati n u m
ton er an d a pal l adi u m ton er . S pl i t ton i n g u si n g t wo di ffer en t
ton er s an d h eat ton i n g w er e al so eval u ated.
Th i ocyan ate gol d ton e r s cr eate a mu ch cool er col ou r , sh ado w
r egi on s al most a ppear bl ack , mi d ton es pu r pl e bl u e an d th e
h i gh l i gh ts
l aven der .
Th i s
is
d epen den t
on
th e
pa per
an d
for mu l as u sed. S ee Fi gu r es 6 -3 , 6-8 , an d 6 -1 8 .
Pl ati n u m ton er cr eate s a gr ey/ bro wn / bl ack ton e . A l th ou gh th e
same str en gth an d ti me i s su g gested for al bu men an d sal t
pr i n ts, i n testi n g th e al bu men h i gh l i gh ts tu r n ed yel l o w an d
73
th e pr i n t bl each e d back on e sto p (Fi gu r e 6 -1 5 ).
For al bu men
th i s for mu l a i s better di l u ted by 5 0 per cen t. Gel ati n si z ed sal t
pr i n ts yel l o wed ver y sl i gh tl y i n h i gh l i gh ts an d th e pl ai n sal ted
paper h i gh l i gh ts r emai n ed wh i te.
Th e
p al l adi u m
ton er
cr eate s
a
cool
gr ey / br o wn
bu t
th e
str en gth of th e for mu l a r api dl y tu r n s th e al bu men h i gh l i gh t
ver y yel l o w (Fi gu r e 6 -1 6 ). In testi n g th e for mu l a was cu t back
to 2 5 per cen t an d th e pr i n t was l eft i n th e ton er for on e
mi n u te.
Gel ati n si z ed sal t pr i n ts sh o wed sl i gh t yel l o wi n g i n
h i gh l i gh ts an d th e pl ai n sal ted paper
h i gh l i gh ts r emai n ed
wh i te.
S pl i t
ton i n g
was
car r i ed
ou t
by
u si n g
gol d
bor ax
ton i n g
fol l o wed by pl ati n u m t on i n g (Fi gu r e 6 -5 ) an d gold thiocyanate
toner followed by platinum toning (Figure 6-20). Wh en spl i t ton i n g ,
gol d
ton er s
mu st
be
u sed
b ef or e
th e
aci di c
pl ati n u m
or
pal l adi u m ton er s. Th e aci d wi l l sl o w or stop th e acti vi ty of th e
al kal i n e gol d ton er s
Tex tbook s sta te ti m e i n th e ton er sh ou l d be: fr om 3 mi n u tes to
1 5 mi n u tes (R ei l l y, 1 9 8 0 ) , 5 to 1 0 mi n u tes (Far ber , 1 9 9 8 ) an d 6
mi n u tes
to
12
mi n u tes
(Web b
an d
R eed,
2 00 0 ) .
Tests
demon s tr ate th at i n a fr esh ton er , 1 mi n u te to 2 mi n u tes i n
th e bath wi l l sh o w ch an ge s an d 3 mi n u tes to 1 0 mi n u tes
su bstan ti al l y ch an ge s th e pr i n t . Ho wever th i s de pen ds on th e
n u mber of pr i n ts th at h ave pr evi ou sl y been th r ou gh th e ton er
Th e test t on i n g bath s wer e at 2 0 ° C. 3 mi n u tes to 5 mi n u tes ;
th i s appear ed to gi ve pr ot ecti on wi th s ome c ol ou r ch an ge.
A l l r eadi n g s i n Tabl e 6 -1 to 6 -3 wer e taken fr om step n u mber
1 1 i n th e ton i n g step wedge s.
74
Figure 6-1 Sodium Chloride – no Toner
Figure 6-2 Sodium Chloride –Gold Borax Toner
Figure 6-3 Sodium Chloride - Gold Thiocyanate
Figure 6-4 Sodium Chloride – Platinum
Figure 6-5 Sodium Chloride- Gold Borax and Platinum
Figure 6-6 Ammonium Chloride + Gelatin - No Toner
75
Figure 6-7 Ammonium Chloride + Gelatin - Gold Borax Toner
Figure 6-8 Ammonium Chloride + Gelatin - Gold Thiocyanate
Figure 6-9 Ammonium Chloride + Gelatin - Platinum Toner
Figure 6-10 Ammonium Chloride + Gelatin - Gold Borax and Platinum
Figure 6-11 Ammonium Chloride + Gelatin - Gold Acetate1
Figure 6-12 Ammonium Chloride + Gelatin - Palladium Toner
Figure 6-13 Albumen No Toner
76
Figure 6-14 Albumen Gold Borax Toned
Figure 6-15 Albumen Platinum Toned
Figure 6-16 Albumen Palladium Toned
Figure 6-17 Albumen Gold Acetate Toner
Figure 6-18 Albumen Gold Thiocyanate Toner
Figure 6-19 Albumen Gold Borax and Platinum Toned
Figure 6-20 Albumen Gold Thiocyanate and Platinum Toned
77
S o di um Chl o r i de
P anto ne ®
S o l i d M att
4 0 75 m
L*
a.
b.
40
19
17
411 m
39
6
5
Gol d Th i ocyan at e Ton er : Fi gu r e
6 -3
7 5 40 m
46
1
-3
Pl ati n u m Ton er Fi gu r e 6 -4
7 5 31 m
50
5
12
Gol d B or ax
Fi gu r e 6 -5
438 m
31
9
2
No ton er : Fi gu r e 6 -1
Gol d B or ax Ton er :
Fi gu r e 6 -2
an d Pl ati n u m Ton er :
Chart 6-2 Sodium Chloride Toning
Ammo ni um Chl o r i de +Ge l ati n
No ton er : Fi gu r e 6 -6
7 5 18 m
40
11
10
Gol d B or ax Ton er : Fi gu r e 6 -7
11 m
42
4
7
Gol d Th i ocyan a te Ton er :
Fi gu r e 6 -8
438 m
31
9
2
Pl ati n u m Ton er : Fi gu r e 6 -9
7 5 33 m
28
5
11
Gol d B or ax & Pl ati n u m Ton er :
Fi gu r e 6 -1 0
7 5 05 m
45
11
24
Gol d A cetate T on e r : Fi gu r e 6 -11
10 m
50
4
6
Pal l adi u m Ton er : Fi gu r e 6 -1 2
874 m
51
9
22
Chart 6-3 Ammonium Chloride and Gelatin
Al bume n
No ton er : Fi gu r e 6 -1 3
7 5 15 m
42
15
16
Gol d B or ax Ton er : Fi gu r e 6 -14
10 m
50
4
6
Pl ati n u m Ton er :
873m
52
7
23
Pal l adi u m Ton er : Fi gu r e 6 -1 6
465 m
68
6
29
Gol d A cetate T on er : Fi gu r e 6 -17
9 m
55
3
6
Gol d Th i ocyan at e Ton er : Fi gu r e
6 -1 8
8 0 21 m
54
10
11
Gol d B or ax an d Pl ati n u m Ton er :
Fi gu r e 6 -1 9
7 5 04 m
52
9
19
Gol d Th i ocyan a te an d Pl ati n u m
Ton er : Fi gu r e 6 -2 0
7 5 19 m
40
11
10
Fi gu r e 6 -1 5
Chart 6-1 Albumen Toning
78
Th e pr i n t col ou r i s sai d to be in fl u en ced by si z e, sh ape, th e
di stan ce b et ween th e si l ver par ti cl es an d th e of r efr acti on
l i gh t th ou gh th e medi u m i n wh i c h th ey ar e di sper se d . Th e gol d
ton i n g modi fi es th e i mage c ol o u r by ch an gi n g th e si z e an d
sh ape of th e si l ver par ti cl es . It r epl ac es si l ver ato ms wi th g ol d
atoms. Th i s en l ar gemen t of th e p ar ti cl es mak es th e i mage l o ok
cool er an d mor e n eu tr al i n to n e (War e, 2 0 0 6. ) . In al kal i n e
ton er s th e ato ms of g ol d r epl ac e on l y o n e of th e si l ver l eavi n g
a cool er col ou r wi th th e ton al r a n ge
r emai n i n g i n tact (R ei l l y,
1 9 80 ) .
Heat ton i n g i s per for med after th e pr oces si n g an d wh en th e
pr i n t i s dr y. M an y su ggest ( Far ber , 1 99 8 , R ei l l y an d K en n edy,
1 9 84 , R ei l l y, 1 98 0 , James, 2 00 2 ) cover i n g th e pr i n t wi th br o wn
paper
an d
pr es si n g
wi th
a
h ot
i r on .
Th i s
d emon str ated
mi n i mal ch an ge . Ho wever a dr y mou n t h eat pr ess wh er e th e
pr i n t i s en cl osed made a su bsta n ti al di ffer en ce to th e col ou r .
Th e paper becam e c ompr e ssed an d si l ver par ti cl e s wer e dr a wn
to th e su r face by th e h eat an d h u mi di ty as sh o wn i n Fi gu r es 6 2 1 an d Fi gu r e 6 -2 2 .
Figure 6-21 Heat Toned High Magnification
79
Figure 6-22 Heat Toned
Th i s h eat an d h u mi di t y ca u s es th e pr i n t to co ol i n col ou r fr om
war m br o wn to bl u e br o wn . Th i s i s cl ear l y appar en t i n th e s tep
we dge i n fi gu r e 6 -2 3 . Th e l i ght i s r efl ecti n g off th e n o w
masse d par ti cl es. A l l paper s t est ed r espon de d by ch an gi n g to
cool er col ou r s i n var yi n g degr ees .
Figure 6-23 Result of Heat Toning
L*
a.
b.
Heat Ton ed: S h ado ws
Pan ton e®
S ol i d M att
B l ack m
12
1
0
Un ton ed : S h ado ws
4 9 75 m
19
17
8
Heat Ton ed: M i d-t on es
7 4 97 m
47
0
16
Un ton ed : M i d-ton e s
7 5 04 m
52
9
19
Heat Ton ed: Hi gh l i gh ts
7 4 99 m
92
-1
14
Un ton ed : Hi gh l i g h ts
4 6 85
86
5
9
Table 6-1 Heat Toning
S el en i u m Ton i n g
Th i s was f ou n d be an u n sati sfact or y ton er for sal t or al bu m en
pr i n ts ei th er befor e or after fi x in g . Th e pr i n ts con stan tl y l oo k
bl each ed ou t. War e ex pl ai n s i t is a con sequ en ce of th e ti n y
par ti cl es ‟ l o w abs or bi n g po wer . Th e si l ver sel en i de an d si l ver
su l fi de
bec ome
se mi -tr an s par en t
appear i n g
as
a
bl each ed
i mage (War e, 1 9 9 4 ).
80
THE FIX
Th e pu r pose of fi x i n g i s t o r emove th e u n r edu ced
si l ver
ch l or i de an d oth er l i gh t -sen si ti ve su bstan ces wh i ch ma y be
pr esen t , gi vi n g stabi l i ty to th e pr i n t
Fi x i n g th e i mage i s compl ex ; for l on g ter m stabi l i ty en ou gh
ti me mu st be al l o wed to di ssol v e th e u n ex posed si l ver wi th ou t
bl each i n g an d damag i n g th e qu al i ty of th e i mage.
R eady-m ade fi x er s wi l l di ssol v e th e si l ver sal ts . However th ese
com mer ci al l y man u fact u r ed fi x e r s , especi al l y aci d h ar den er
fi x er s, ar e n ot su i tabl e for sal t pr i n ts . Th e y bl each ou t th e
n an o-par ti cl es of si l ver , weaken i n g th e pr i n t s den si ty . Th i s i s
ex acer bated wh er e gel ati n i s u se d i n th e co ati n g or th e si z i n g
of th e pr i n t.
A ddi n g 0 . 2 % of sodi u m car bon ate to a 1 0 % fi x er of sodi u m
th i osu l fate mak es a sl i gh tl y al k a l i n e fi x er bath stoppi n g aci ds
fr om
decom posi n g
th e
sodi u m
th i osu l fate
an d
l i ber ati ng
su l ph u r . A ci d fi x er bath s cau se b l each i n g i n th e h i gh l i gh ts an d
mi d
ton es
by
attac ki n g
th e
fi n e
si l ver
metal l i c
par ti cl es
use
mi n i mi se
(R ei l l y, 1 98 0 ) .
Th e
fi x er
sh ou l d
be
made
ju st
befor e
to
decom posi ti on . S odi u m th i osu l fa te i n i ts dr y for m i s r el ati vel y
stabl e. It i s u n stabl e wh en di ss ol ved i n water , de com pos i n g to
sodi u m su l ph i te an d el e men tal su l ph u r (R ei l l y, 1 98 0 ) .
D ar k mottl e d s tai n s i n di cate d th e fi x er i s ex h au sted, wh er e as
yel l o wi n g of th e pr i n t or yel l o w stai n s i n di c ated th e p r i n t i s
l eft too l on g i n fi x er .
T wo fi x er bath s ar e es sen ti al as th i osu l fat e i on s mu st b e
pr esen t i n ex cess or i n sol u bl e co mpl ex es ar e for med wh i ch ar e
on l y sol u bl e i n fr esh th i osu l fate .
1 . In th e fi r st bath si l ver th i osu l fate compl ex e s for m .
2 . In th e secon d bath i n sol u bl e co m pl ex es a r e r emoved .
Pr i n ti n g ou t paper s after fi x i n g become yel l o w/ r ed/ br own i n
col ou r . R ei l l y (1 9 8 0 ) su ggests th e s i l ver par ti cl es pack cl os e l y
81
togeth er
as
th e
fi x er
di ssol ves
u n r edu ced
si l ver
ch l or i de.
A n oth er th eor y su ggest th e yel l owi n g of th e pr i n t i n th e fi x er
i s du e t o th e tr an sf or mati on of t h e si l ver to a l o wer r efr acti ve
po wer so th e abs or pti on i s mov ed to th e sh or t wave l en gth s
(Cl er c, 1 9 4 4 ). Th e secon d th eor y i s mor e pr oba bl e as th e si l ver
par ti cl es adh er e to th e paper fi br es, th e paper s d o con tr act
an d ex pan d bu t th i s yel l o w col o u r wou l d be a ppar en t i n th e
fi r st con tact wi th th e water i f R ei l l y‟ s th eor y was cor r ect.
THE CLEARING AGENT
Th e u n pr otected paper base of t h e sal ted paper an d al bu men
pr i n ts al l ows a gr eater absor pti o n of sodi u m th i osu l fat e th an
mass pr odu ced devel opi n g ou t paper s. For th i s r ea son i t i s
al most i mp os si bl e to r emo ve al l th e tr aces of fi x er s wi th ju st
wa ter . A wash i n g ai d i s th er efor e essen ti al for m or e co mpl ete
r emoval of dama gi n g si l ver -th i os u l fate compl ex e s.
THE FINAL WASH
In su ffi ci en t wash i n g i s sti l l th e mai n cau se of de ter i or a ti on of
sal t pr i n ts . Fa ctor s fou n d f or c r i ti cal wa sh i n g ar e a gi tati on
an d water r epl a cemen t du r i n g t h e wash . A l s o mai n tai n i n g a
temper atu r e above 2 0 ° C. an d al l owi n g t i m e for th e fi x er to
di ssi pate ou t of th e paper i n to th e wa ter .
D epen di n g on th e th i ckn e ss of th e paper , th e pr i n ts sh ou l d
r ecei ve at l east a 3 0 - mi n u te wa sh . Heavi er paper s an d mor e
den sel y coa ted pap er s su ch as al bu men wi l l r equ i r e l on ger
wa sh i n g
ti mes
th an
pl ai n
sal t ed
pr i n ts
(L avedr i n e,
2 00 3 ).
Testi n g fou n d th at 2 h ou r was n ot adequ ate i n r emovi n g al l
tr aces of su l ph u r for th e fi x er .
82
TE S TS FOR R E S ID UA L S OD IUM THIOS UL FA TE
A r ch i val
pr ocessi n g
pr acti ces
wer e
adh er ed
to
du r i n g
th e
var i ou s test s . Th e K odak Hyp o T est S ol u ti on HT1 a was u se d to
i den ti fy r esi du al sodi u m th i osu l fate. E ven th ou gh th e se test s
i n di cat ed n o r esi du al s odi u m th i osu l fate , th e E D A X i n di cated
oth er wi se.
Th e al bu men an d star ch bi n der s gave th e h i gh est
r eadi n gs of su l ph u r . G el ati n h a s th e l o we st r eadi n g , bu t al l
i n di cated
th e
pr esen ce
of
su l ph u r .
A l bu men
is
per h aps
ex pected to r etai n so me su l ph u r attr i bu ted t o th e su l ph u r i n
th e egg wh i te.
E ach step of pr oces si n g th e pr i n t n ot on l y i n fl u en ces th e pr i n t
col ou r bu t al so i t s l i fe. Th e mo s t dr amati c ch an ge i n th e sal t
pr i n t col ou r came th r ou gh th e var i ou s ton i n g for mu l as.
83
Chapter 7 DISCUSSION
Wi l l i am Hen r y Fox Tal bot ‟ s or i gi n al sal t pr i n t for mu l a of a
sodi u m ch l or i de sol u ti on ( co m mon tabl e sal t) an d a si l ver
n i tr ate
sol u ti on
appear s
si mp l e .
Ho wever ,
si l ver
n i tr ate
i n ter acts wi th n u mer ou s or gan i c an d i n or gan i c su bstan ces.
S tai n i n g or ch emi cal „foggi n g ‟ appear s i n th e pr in t u n l ess th e
paper , paper coa ti n g tool s an d t h e wa ter for th e for mu l as ar e
fr ee fr om an y con tami n ati n g mat t er .
Th e bi n der s su spen ded th e ch l o r i de sol u ti on an d acted as a
si z i n g
agen t
h ol di n g
back
si l ver
ch l or i de
sol u ti on s
bei n g
absor b ed i n to th e paper fi br es. It i s th i s su b str ate or l ayer
wh i ch
r efr acts
su bstr ate
th e
l i gh t
war mer
an d
th e
con sequ en tl y
pr i n t
col ou r .
th e
th i cker
th e
Th e
war mth
an d
acu tan ce of th e pr i n t can be c on tr ol l ed by th e a mou n t of
gel ati n si z i n g. A l th ou gh al bu men war m ed th e i ma ge col ou r an d
gave br i l l i an ces to th e i ma ge, th e ton al r an ge was n ot as
ex ten si ve as th e pl ai n sal ted or gel ati n si z ed paper s. S tar ch i s
typi cal l y a du l l su bstr ate an d as a r esu l t r efr acts l i ttl e l i gh t .
In
spi te
of
th at
it
h ol d s
de ta i l
in
both
th e
sh ado w
an d
h i gh l i gh t r egi on s ex cepti on al l y wel l .
S u bstan ti al r esear ch wa s n ece s sar y wh en sel ec ti n g su i tabl e
paper s for th e sal t pr i n t tests o wi n g to th e en or mou s r an ge of
paper types av ai l abl e.
E x pl or i n g th e paper su r face u si ng th e Nova Nan oS E M pr ovi ded
an i n si gh t to h ow si z ed pa per i n fl u en c es th e pr i n t . Th e paper
ch oi ce di d i n fl u en ce th e col ou r , con tr ast an d t on al separ ati on
of th e i mage. S mooth h ar der fi n i sh ed , su r face si z ed paper s
gave a sh ar per mor e br i l l i an t i mage wi th c ool er col ou r ton es .
S i l ver n i tr ate sol u ti on s r espon d u n favou r abl y to an y ch emi cal
paper
addi ti ves
col ou r
paper s
th er efor e
can
be
on l y
u sed.
qu al i ty 1 00 % cotton ,
AKD,
th e
syn th eti c
water
ar ch i val
84
i n ter n al si z i n g agen t , sti l l cr eated ch emi cal foggi n g wi th th e
ex cepti on
of
al bu men
pr i n ts .
An
u n der stan di n g
of
th e
str u ctu r e an d comp osi ti on of pa per s was an e ssen ti al t ool i n
con tr ol l i n g th e col ou r an d th e fi nal l ook of th e pr i n t .
A gl ass r od an d a syr i n ge pr ovi de d gr eater accu r acy over th e
amou n t of sol u ti on th at wa s ap pl i ed. Th e c oati n g wa s m or e
even an d th e r ati o bet ween th e sal t an d th e si l ver n i tr ate
sol u ti on was mor e c on tr ol l ed. B y i n cr easi n g th e vol u me of th e
al bu men
an d
r esol ved.
a r r owr o ot
A ppl yi n g
th e
sol u ti on s,
sec on d
coati n g
coati n g
of
pr obl e ms
al bu men
wer e
was
con si sten tl y su c ces sfu l on ce th e ch l or i de i n i sopr o pyl al c oh ol
wa s omi t ted.
M an y th eor i es state th e c ol ou r of a ph ot ogr aph de pen ds on th e
si l ver par ti cl e si z e an d sh ape . T h e col ou r of metal col l oi d s i s
a r esu l t of th e abs or pti on an d s c atter i n g of l i gh t . R M IT Ph ysi cs
depar tmen t‟ s FE I No va Nan oS E M wi th an E D A X X -r ay de tect or
wa s u sed to s ear ch for a r el ati on sh i p bet ween th e var yi n g
si z e s
an d
sh apes
of
si l ver
par ti cl es
an d
h ow
th e y
ar e
di sper sed wi th i n th e pr i n t to affect col ou r .
Th e si z e var i ati on s of th e si l ver par ti cl es wi th i n a si n gl e pr i n t
sampl e wer e u n ex pec ted . Wr i tte n mater i al sta tes th e si z e of
si l ver par ti cl es r a n g es fr om 10n m to 1 3 0 n m (War e, 1 9 94 ) .
A l bu men par ti cl es ar e sai d to be l ess th an 3 n m to 50 n m, wi th
most bet ween 5 n m an d 2 0 n m (Rei l l y an d K en n edy, 19 84 ) . It
wou l d be ex pe cted f or a speci fi c col ou r , th e par ti cl es wou l d be
wi th i n a si z e r an ge. For ex ampl e , at th e smal l er en d of th e
scal e , yel l o w si l ver par ti cl es wo u l d r an ge fr om 1 0 n m to 2 0 n m
an d at th e l ar ge r en d of th e scales par ti cl es of a gr ey/ gr een
col ou r wou l d r an ge fr om 1 2 0 n m to 1 3 0 n m (War e, 1 9 94 ) . Th i s
di d n ot appe ar to be so. S i l ver par ti cl es r an ged fr om 1 . 4 5 µ m
to 8 2 0 n m. In som e cas es i t w ou l d be ex pe cted th e si l ver
par ti cl es may cl u mp tog eth er maki n g th e par ti cl es appear as
on e . Th e amou n t of sa mpl e s m i gh t h ave l ed to a l evel of
con fi den ce i n cer tai n fi n di n gs bu t th e evi den ce r e th e si z e
came fr o m th e ex ami n ati on of a l ar ge n u mber of sa mpl es of
si l ver par ti cl es sh o wi n g th e sa mpl es ex ceede d th at o f th e
85
pr evi ou sl y r epor te d ph o tol yti c s i l ver par ti cl es .
E x ampl es of
th ese par ti cl e si z e s ar e sh o w i n Fi gu r e 5 -4 ti tl ed B r on z i n g
Hi gh M agn i fi cati on .
A l th ou gh th e par ti cl es ‟ si z e an d sh ape may h ave so me ef fect
on
col ou r ,
paper s,
fi n di n gs
si z i n g,
of
th i s
ex posu r e,
r e sear ch
h u midi ty ,
su ggest
th e
th e pr ocessi n g
bi n der s,
an d i n
par ti cu l ar ton i n g , h ave a mu ch greater effect.
In vesti gati n g th e t on e r epr odu cti on of th e sal t pr i n t wa s ti me
con su mi n g. E ach n egati ve type wa s fou n d to h ave n u mer ou s
var i ati on s an d pr obl e ms. Th e t i me sp en t on th e n egati ve,
especi al l y th e di gi tal as pect, be came di s pr opor ti on ate t o th e
en ti r ety of th i s r esear ch paper . A l th ou gh a gr eat deal mor e
ex pl or ati on cou l d be car r i ed ou t, th e r esu l ts at th i s poi n t wer e
fel t to be r eason abl y con cl u si ve.
Th e fi l m n egati ve offer s th e gr eatest ton al r an ge, pr ovi di n g
su btl eti es o f ton e s th at th e di gi ta l n egati ve cou l d n ot pr odu ce.
E x ten si ve testi n g pr ov ed th at Il for d FP4 n egati ves pr oces sed
i n th e dou bl e str en gth PM K devel oper pr ovi de d th e gr eat est
con ti n u ou s ton e an d pr odu ced t h e ex tr a den si ty de si r abl e for
sal t pr i n t i n g. Th i s i s wh en th e sa l t pr i n ts ‟ sel f -ma ski n g abi l i ty
wa s u ti l i sed to max i mi se th e ton a l r an ge.
D ots mak i n g u p an i n kjet n egat i ve ar e at on e l evel bu t the
si l ver an al ogu e n egati ve pr ovi de s a gr adati on of t on es at man y
l evel s. A ddi ti on al l y, a r el i ef of di ffer en t l evel s i n th e fi l m
emu l si on o ffer s fu r th er di men si o n s. PM K devel oper f or med th e
gr eatest r el i ef i n th e fi l m emu l si on .
Th e i n kjet n egati ves wi th
si mi l ar col ou r s to th e FP4 / PMK n egati ve pr oved to su r pass a
n u mber of ty pes of an al ogu e fi l m n egati ves tes ted i n ter m s of
ton al r an ge .
Th e col ou r an d c on tr ast of th e pr i n t ar e i n fl u en ced by th e
i n ten si ty an d col ou r of th e ex posi n g l i gh t. A UV l i gh t b ox
offer s
vi si bl e
s tabi l i ty
an d
spectr u m
ar e
r epeatabi l i ty
var i abl e
wh i l e
an d
su n l i gh t ‟ s
compl ex .
Th e
UV
an d
i mage s
ex posed i n th e su n l i gh t ten d to r etai n war mer ton es an d
86
gr eater den si ty. Th i s war mth ap pear s to devel op th r ou gh th e
di ffer i n g vi si bl e an d UV r ays an d al so h u mi di ty con ver ti n g
mor e si l ver ch l or i de to me tal l i c si l ver wh i ch gr avi tat e to th e
pr i n t su r face.
Tests wi th cu t -off fi l ter s pr oved con cl u si vel y t h e sen si ti vi ty
of th e si l ver ch l or i de t o th e vi si b l e spectr u m i s far mor e wi de r an gi n g th an pr evi o u sl y r epor ted i n var i ou s wr i tten mater i al .
A cti n i c
BL
40
mi r r or ed th e
watt
mer cu r y
spectr al
qu al i ty
vapou r
fl u or escen ce
of th e sol ar
l am ps
spectr u m.
Th i s
ex pl ai n s th e poor ou tcome fr om fi l m wi th a h i gh base fog or
u n bu i l t UV fi l ter s su ch as K odak D u r ocl ear ™ as i n su ffi ci en t
l i gh t wa s tr an smi t ted at th e si l v er ch l or i de ‟ s peak sen si ti vi t y.
Ho w th e l on ger wave l en gth s i n th e spectr u m pl ay a p ar t i n
ex ten di n g
th e
ton al
r an ge
an d
col ou r s
cal l s
for
p ossi bl e
fu r th er r esear ch .
D espi te adh er i n g to ar ch i val pr acti ces i n pr o cessi n g an d i n
par ti cu l ar th e wash i n g, su l ph u r wa s sti l l fou n d t o be r esi di n g
i n th e paper .
Th e var i ou s me t h ods of t esti n g for r esi du al
sodi u m th i osu l ph at e (r esu l ti n g i n su l ph u r ) appear to be l ess
th an adequ ate. Th e E D A X X -r ay detector r eveal ed th at bi n der s
ex pected
to
pr ote ct
th e
si l ver
par ti cl es
fr om
su l ph u r
attach men t appear i n eff ecti ve. S u l ph u r was di s cover ed on th e
si l ver par ti cl e s o f gel ati n bi n de r s . Ho wever on al bu men an d
star ch bi n der s th e atomi c per cen tage was gr eater . S u l ph u r h as
a damagi n g effect on i mage stabi l i ty. Fu r th er r esear ch on each
of th e pr oce ssi n g ste ps may co n tr i bu te to establ i sh m en t
meth od s
to
ex ten d
pr i n t
i mag e
stabi l i ty
of
th e
sal t
of
an d
al bu men pr i n t.
E ach step of pr oces si n g i n fl u en ces th e pr i n t col ou r an d i ts
l i fe. A pr ocedu r e for th e i n i ti al wa sh i n g stag e wa s d evel ope d
to
el i mi n ate
th e
stai n i n g
th a t
was
appar en t
th r ou gh ou t
pr ocessi n g.
Th e most dr amati c ch an ge i n t h e col ou r of sal t pr i n t came
th r ou gh
th e
var i ou s
ton i n g
for mu l as.
M an y
of
th e
ton i n g
for mu l as pr oved to be t oo con c en tr ated for th e al bu men an d
87
gel ati n pr i n ts. Th i s was easi l y r esol ved by di l u ti on of th e
ton er wh i ch appear ed to h ave mi n i mal effect on th e l on g t er m
stabi l i ty.
Th e ear l y pr oces ses ar e oft en tau gh t an d con si der ed pu r el y an
ar t for m wh er e a mi sta ke or acc i den t i s con si der ed cr eati ve.
Th e h i stor y an d th e ch emi cal acti vi ty, r espon se s an d l on gevi ty
ar e n ei th er di scu ssed n or even con si der ed r el evan t. A l l too
often , tex t on th e sal t pr i n t i s w r i tten i n a wa y wh i ch al mo st
bel i ttl es th e pr oce sse s. It cl ose s a d oor on th e p eopl e wh o
wi sh to ex pl or e, u n der stan d an d con tr ol th e pr oces s. A l th ou gh
often i t i s cl ear fr om wh er e th e wr i tten mater i al or i gi n ate s, i t
i s di sapp oi n ti n g so man y au th o r s h ave n ot r efer en ce d th ei r
or i gi n al sou r ce.
88
Chapter 8 CONCLUSION
S al t pr i n ti n g i s an in ex act sci en ce.
D espi te r i gor ou s car e an d atten ti on to coati n g, ex posu r e an d
pr ocessi n g, th e n u mber of var i a bl es at ever y ph ysi cal stag e
ten ds to ma ke ex act r epeatabi l i ty i mpr obabl e . It i s di ffi cu l t to
pr ovi de a cl ear -cu t r ati on al e for th e col ou r an d appear an ce of
th e sal t pr i n t i n ter ms of th e se var i abl es u n l ess th ey ar e
man aged an d addr es sed du r i n g each stage of pr odu cti on .
Th er e ar e a n u mb er of mech an i s ms t o c on tr ol th e col ou r an d
th e appear an ce of th e sal t pr i n t.
Ch l or i de for mu l as
an d
addi ti v es al l o w s ome con tr ol of col ou r an d con tr ast bu t i t i s
th e bi n der s th at ch an ge h o w th e si l ver i mage si ts on th e pa per
su r face wh i ch of fer gr eater con tr ol . Th i s i s attr i bu tabl e to
l i gh t r efr acti n g th r ou gh th ese b i n der s as th ey l i ft th e i mage
u p or ou t of th e paper fi br es.
Th e p aper s u sed for sal t pr i n t i n g h ave a con si der abl e effect
on th e col ou r an d ton al r an ge . T h e paper mi l l s pr odu ce si z ed
paper s wi th h ar d or soft su r face s . Th ese su r faces dr ama ti cal l y
affect th e ton al r an ge an d th e pr i n t col ou r , var yi n g fr om co l d
bl u e / br own
c ol ou r s
to
war m
r i ch
pu r pl e/ r ed/ br own .
Un der stan di n g th e con str u cti on an d comp osi ti on of th e pa per
pr ovi des th e abi l i ty t o pr edi ct an d con tr ol col ou r . S peci fi c
paper s can be sel e cted t o pr ovi de defi n ed ton al r an ges an d
acu tan ce.
Th e ex ten si ve r esear ch i n to fi n d i n g th e best type o f n egati ve
wa s val u abl e. Th e Il for d FP4 n egati ve wi th th e gr een / br own
tan n i n g stai n fr om th e PM K devel oper pr ovi ded a su b stan ti al
ton al
In kjet
r an ge
by u ti li si n g th e in tr i n si c sel f -mas ki n g abi l i ty .
n egati ve s
pr ovi ded
a
wh e n
r eason abl e
du pl i ca ti n g
ton al
ran ge
th e
PM K
al th ou gh
stai n
th ey
col ou r
di d
n ot
separ ate ton e s or per for m wel l i n th e h i gh l i gh ts an d sh ado w
r egi on s. Th ey di d h o wever per for m better i n con tr ast an d
89
ton al r an ge th an man y an al ogu e fi l ms an d n egati v e en l ar gi n g
pr ocess es.
Ch oosi n g t o u se a con tr ol l ed UV l i gh t box r ath er th an su n l i gh t
to
ex pose
pr ovi d e d
pr edi ctabi l i ty
bu t
l ost
mu ch
of
th e
spectr u m to wh i ch si l ver ch l or i de i s al so sen si ti ve. Th e vi si bl e
spectr u m an d th e h u mi di t y c o n tr i bu te to ex tr a war mth i n
col ou r an d den si ty of th e fi n al p r i n t. E x posi n g th e pr i n t cl ose
to br on z i n g i n di cates a h i gh p or ti on of si l ver ch l or i de h as
been con ver ted to metal l i c si l ve r . Th i s makes th e pr i n t l ess
vu l n er abl e to ox i dati on , assi st i n g i n th e pr i n ts‟ l on gevi ty.
Ton i n g offer s th e gr eatest con t r ol an d dr amati c ch an ge of
col ou r wh i l e al s o pr ote cti n g th e l i fe of th e pr i n t . P r i n ted
mater i al on ton i n g an d th e o th er pr ocessi n g meth od s h o wever
wa s fr au gh t wi th con tr adi ctor y i n for mati on . Th e devel op men t
of a pr e- wash m et h od r esol v ed m a n y of th e stai n i n g pr obl ems .
D espi te
al l
effor ts
to
u se
th e
most
ar ch i val
meth ods
of
pr ocessi n g , th e E D A X X -r ay detector i n di cated su l ph u r wa s
sti l l pr esen t i n th e paper . E ven t h ou gh t est s for r esi du al fi x er
i n di cated th e paper
was fr ee
f r om th i s damagi n g su l ph u r
el emen t.
Th e th eor y of th e par ti cl e si z e a n d sh ape di ctati n g th e col ou r
of th e sal t pr i n t fel l sh or t wh e n compar i n g th e col ou r s th at
ar e con tr ol l ed by th e bi n der s, ton er s an d paper s. Th e Nan oS EM
pr ovi ded i mage s i n di cati n g th e si z e of th e si l ver par ti cl es i n
most sam pl e s wer e too di ver se i n si z e to di cta te on e l i mi t ed
col ou r r an ge.
A l th ou gh su l ph u r on th e si l ver par ti cl e s may
h ave so me bear i n g on c ol ou r , t h e paper bi n der s, ton er s an d
ex posu r e h ave a far gr eater effect an d con tr ol on th e fi n al
col ou r of th e sal ted pap er pr i n t.
Th e sal t pr i n t col ou r an d ton es th er efor e can be con tr ol l ed
an d pr edi cte d. Th i s h o wever i s l i mi ted by th e abi l i ty of th e
sal t pr i n ter to r epeat each of th e oper ati on s con si sten tl y .
90
APPENDIX 1 SALT FORMULAS
SODIUM CHLORIDE FORM ULA
D i sti l l ed Water
2 5 0 ml
S odi u m ch l or i de
5 gm
Meth od :
A dd th e sal t to th e r oom te mper a tu r e di sti l l ed wa ter . Th i s wi l l
di ssol ve ea si l y an d i s r eady for u se wh en di ss ol ved.
AMMONIUM CHLORIDE FORMULA
D i sti l l ed Water
2 5 0 ml
A mmon i u m ch l or i de
5 gm
Meth od :
A dd th e sal t to th e r oom te mper a tu r e di sti l l ed wa ter . Th i s wi l l
di ssol ve ea si l y an d i s r eady for u se wh en di ss ol ved.
SODIUM CHLORIDE SOLUTION + GELATIN
D i sti l l ed Water
5 0 ml
Gel ati n
2 gm
D i sti l l ed Water at 3 8 ° C
2 0 0 ml
S odi u m ch l or i de
5 gm
Meth od :
1 . M i x 2 gm of gel ati n wi th 5 0 ml of di sti l l ed water at r oom
temper atu r e an d l eave for 1 0 mi n u tes.
2 . Heat th e 2 0 0 ml of di sti l l ed wa ter to 3 8 ° C.
3 . A dd th e sal t wh en di ssol v ed .
4 . S ti r i n th e gel ati n.
5 . Th e sol u ti on i s r eady wh en co ol e d to a bou t 2 0 ° C.
91
AMMONIUM CHLORIDE SOLUTION + GELATIN
D i sti l l ed Water
5 0 ml
Gel ati n
2 gm
D i sti l l ed Water at 3 8 ° C
2 0 0 ml
A mmon i u m Ch l or i de
5 gm
Meth od :
1 . M i x 2 gm of gel ati n wi th 5 0 ml of di sti l l ed water at r oom
temper atu r e .
2 . L eave for 1 0 mi n u tes.
3 . Heat th e 2 0 0 ml of di sti l l ed wa ter to 3 8 ° C.
4 . A dd th e sal t wh en di ssol v ed .
5 . S ti r i n th e gel ati n.
6 . Th e sol u ti on i s r eady wh en co ol e d to abou t 2 0 ° C.
SODIUM CHLORIDE + SODIUM CITRATE
D i sti l l ed Water
2 5 0 ml
S odiu m chl ori de
5 gm
S odi u m ci tr ate
5 gm
Meth od :
1 . A dd th e sal t to th e di sti l l ed wa te r . It wi l l di ssol v e easi l y.
2 . A dd 5 gm sodi u m ci tr ate; i t i s r eady for u se wh en th i s h as
di ssol ve d.
AMMONIUM CHLORIDE + SODIUM CITRATE
D i sti l l ed Water
2 5 0 ml
A mmon iu m Ch l ori de
5 gm
S odi u m ci tr ate
5 gm
Meth od :
1 . A dd th e sal t to th e di sti l l ed wa te r . It wi l l di ssol v e easi l y.
2 . A dd 5 gm sodi u m ci tr ate; i t i s r eady for u se wh en th i s h as
di ssol ve d.
92
SODIUM CHLORIDE + POTASSIUM DICHROMATE
D i sti l l ed Water
2 5 0 ml
S odiu m chl ori de
5 gm
Meth od :
1 . A dd th e sal t to th e di s ti l l ed wa te r . It wi l l di ssol v e easi l y.
2 . Take 3 0 ml of sal t sol u ti on .
3 . A dd 2 dr ops of th e 5 % potassi u m di ch r omate sol u ti on .
AMMONIUM CHLORIDE + POTASSIUM DICHROMAT E
D i sti l l ed Water
2 5 0 ml
A mmon i u m Ch l or i de
5 gm
Meth od :
1 . A dd th e sal t to th e di sti l l ed wa te r . I t wi l l di ssol v e easi l y.
2 . Take 3 0 ml of sal t sol u ti on .
3 . A dd 2 dr ops of th e 5 % potassi u m di ch r omate sol u ti on .
POTASSIUM DICHROMATE 5% SOLUTION
D i sti l l ed Water at 2 0 ° C
1 0 0 ml
Potassi u m di ch r omate
5 gm
Meth od :
1 . Heat water to 2 0 ° C .
2 . Pu t on gl oves, eye pr ote cti on an d mask.
3 . D i ssol ve po tassi u m di ch r omate i n th e di sti l l ed water .
4 . S tor e i n a smal l stopper ed br o wn bottl e .
ALBUMEN FORMULA – AMMONIUM CHLORIDE
A l bu men (egg wh i t e)
250 ml (8 - 10 eggs)
Gl aci al aceti c aci d
0 . 5 ml
D i st i l l ed water
8 ml
A mmon i u m ch l or i de
4 gm
Meth od :
1 . Car efu l l y separ ate e gg wh i te s r emov i n g al l con tami n ati on of
yol k, str i n gy ti ssu e, bl o od or sh e l l fr om th e egg wh i te s.
3 . A dd al l ch emi cal s .
4 . B eat th i s sol u ti on u n ti l i t i s con ver ted to fr oth .
5 . L e t th e sol u ti on si t for 2 4 h ou rs i n th e r efr i ger ator .
93
6 . B r in g to r oom temper atu r e .
7 . S tr ain th ou gh mu sl i n or ch eesecl oth .
8 . Cover an d r efr i ger ate for 1 we ek to fer men t.
ARROWROOT FORMULA (WALL AND JORDAN, 19 75)
D i sti l l ed water
7 5 0 ml
A r r owr oot star ch
2 0 gm
D i sti l l ed water
2 5 0 ml
A mmon i u m ch l or i de
1 4 gm
S odi u m car bon ate
2 3 gm
Ci tr i c aci d
7 gm
Meth od :
1 . M i x th e arr owr oot star ch wi th abou t 2 0 ml of th e 7 50 ml
vol u me of th e di sti l l ed water mak i n g a smooth cr eam y
su spen si on .
2 . B r i n g to th e b oi l th e bal an ce of di sti l l ed water .
3 . Gr adu al l y add th e star ch wh i l e st i r r i n g.
4 . Con ti n u e to boi l u n ti l th e l i qu i d is tr an sl u cen t.
5 . In th e secon d am ou n t of di sti l l ed wat er di ssol ve th e
ammon i u m ch l or i de, s odi u m car b on ate an d ci tr i c aci d . Wh i l e
addi n g th e ci tr i c aci d th i s sol u ti o n wi l l effer vesc e.
6 . A dd th e sol u ti on to th e ar r owr o ot an d boi l for 5 mor e
mi n u tes. Th e smel l of a mm on i a wi l l be qu i te str on g .
7 . S tr ai n th r ou gh mu sl i n or ch eese cl oth wh i l e h ot an d al l o w t o
cool .
8 . R emove an y s ki n th at h as for med befor e appl yi n g to th e
paper .
SILVER NITRATE SENSI TIZING FORMULA
D i sti l l ed or de -mi n er al i z ed water
5 0 ml
S i l ver n i tr ate
6 gm
Meth od :
1.
Wi th gl oves an d eye pr ot ecti on i n pl ace, a dd th e si l ver n i tr ate
to th e di sti l l ed wat er at r oom te mper atu r e.
94
2.
S tor e i n a br own gl ass bottl e.
APPENDIX 2 TONER FORMULAS
GOLD BORAX TONER (FARBER, 1998)
D i sti l l ed water
1 0 00 ml
S odi u m tetr abor ate (bor ax )
6 gm
Gol d ch l or i de 1 % sol u ti on
1 2 ml
Meth od :
1 . Heat di sti l l ed wat er to 3 8 ° C.
2 . A dd th e s odi u m t etr abor ate .
3 . A dd th e gol d ch l or i de.
SODIUM ACETATE GOLD TONER (JAMES, 2002)
D i sti l l ed water
1 0 00 ml
S odi u m acetate
1 0 gm
Gol d ch l or i de 1 % sol u ti on
1 0 ml
Meth od :
1 . Heat di sti l l ed wat er to 3 0 ° C.
2 . A dd th e sodi u m ace tate .
3 . A dd th e gol d c h l or i de.
THIOCYANATE GOLD TON ER1 (REILLY, 1980)
D i sti l l ed water
S odi u m th i ocyan ate
Gol d ch l or i de 1 % sol u ti on
5 0 0 ml
9 gm
3 5 ml
Meth od :
1 . Heat di sti l l ed wat er to 3 0 ° C.
2 . A dd th e sodi u m t h i oc yan ate .
3 . A dd t h e gol d ch l or i de.
95
96
THIOCYANATE GOLD TON ER 2 (CRAWFORD, 1979)
D i sti l l ed water
5 0 0 ml
S odi u m th i ocyan ate
2 . 5 gm
Tar t ar i c aci d
S odi u m c h l or i de
1 gm
2 . 5 gm
Gol d ch l or i de 1 % sol u ti on
1 0 ml
D i sti l l ed water to mak e 5 0 0 ml
Meth od :
1 . Heat di sti l l ed wat er to 3 0 ° C.
2 . A dd th e s odi u m t h i oc yan ate .
3 . A dd tar tar i c aci d.
4 . A dd sodi u m ch l or i de.
5 . A dd th e gol d ch l or i de.
6 . A dd wa ter to make 5 0 0 ml .
PLATINUM TONER (JAMES, 2002) ADJUSTED
D i sti l l ed water at 3 0 ° C
10 00 ml
Potassi u m ch l or opl ati n i te 2 0 %
2 . 0 ml
Ci tr i c aci d
2 . 5 gm
Meth od :
1 . Heat di sti l l ed wat er to 3 0 ° C.
2 . A dd th e Potassi u m ch l or opl ati n i t e .
3 . A dd th e ci tr i c aci d.
4 . Th e ton er i s r eady for u se wh en cool ed to 2 0 ° C.
PALLADIUM TONER (JAMES, 2002) ADJUSTED
D i sti l l ed water
1 0 00 ml
S odi u m ch l or opal l adi te 1 5 % sol u ti on
2 .0 ml
Ci tr i c aci d
2 .5 gm
S odi u m ch l or i de
2 .5 gm
Meth od :
1 . Heat di sti l l ed wat er to 3 0 ° C.
2 . A dd th e S odi u m ch l or opal l adi te.
3 . A dd th e ci tr i c aci d, di ssol ve.
4 . A dd th e S odi u m ch l or i de .
5 . Use wh en co ol ed to 2 0 ° C.
97
A P P E N D I X 3 D E V E L O P E R A N D F IX E R F O R M U L A S
PMK DEVELOPER (HUTCHINGS, 1992)
S o l uti o n A
D i sti l l ed water at r oom te mper at u r e
7 5 0 ml
M etol
1 0 gm
S odi u m bi su l fi te
2 0 gm
Pyr ogal l ol
1 0 0 gm
Water to make
1 0 00 ml
S o l uti o n B
D i sti l l ed water at r oom te m per at u r e
1 4 00
S odi u m metab or ate
6 0 0 gm
Water to make
2 0 00 ml
Meth od :
S to c k S ol uti o n A
1.
Wei gh ou t th e sodi u m bi su l fi te.
2.
A dd a pi n ch of th e sodi u m bi su l fi te to th e 7 5 0 ml of water
an d set th e r emai n der asi de.
3.
A dd th e metol an d sti r u n ti l com pl etel y di s sol ve d.
4.
A dd r emai n i n g sodi u m bi su l fi te, sti r u n ti l di ssol ved.
5.
If a ven ti l ati n g h ood i s n ot avai l a bl e , measu r e th e
pyr ogal l ol ou tsi de.
6.
Pu t on gl oves, mas k an d eye pr ot ecti on .
7.
M easu r e ou t th e pyr ogal l ol an d add to th e sol u ti on .
S to c k S ol uti o n B
1 . D i ssol ve th e so di u m me tabor ate i n th e 1 40 0 ml of water .
2 . A dd wa ter to make 2 0 0 0 ml .
3 . S tor e i n br own gl ass bot tl es cl ear l y mar ked.
98
FIXER
Water
7 5 0 ml
S odi u m th i osu l fate
1 5 0 gm
S odi u m car bon ate
Water to make
2 . 5 gm
1 0 00 ml
Meth od :
1 . Heat th e 7 5 0 ml of water to 3 0 ° C .
2 . A dd th e s odi u m th i osu l fat e.
3 . A dd th e sodi u m car bon ate.
4 . A dd wa ter to make 1 0 0 0 ml .
KODAK FIXER TEST SOL UTION FT1
Water
1 0 0 ml
Potassi u m i odi de
1 9 gm
Meth od :
1 . Heat water to 3 8 ° C .
2 . A dd potas si u m i odi de.
3 . It i s r eady for u se wh en di ss ol ve d an d cool ed t o 2 0 ° C.
KODAK FIXER TEST SOL UTION ST-1
Water at 3 8 ° C
1 2 5 ml
S odi u m su l ph i de
2 gm
Meth od :
1 . Heat water to 3 8 ° C
2 . A dd S odi u m su l ph i de.
3 . R eady for u se wh en di ss ol ved an d cool ed t o 2 0 ° C.
CLEARING AGENT
Water at 3 0 ° C
S odi u m su l ph i te
1 0 00 ml
1 0 gm
Meth od :
1 . Heat water to 3 0 ° C.
2 . A dd S odi u m su l ph i te.
3 . Wh en di ssol ved an d th e t emper at u r e i s appr ox i matel y 2 0 ° C
i t i s r eady for u se.
99
KODAK HYPO TEST SOLU TION HT1A (RESIDUAL FIXER)
D i sti l l ed water at 2 0 ° C
1 8 0 ml
Potassi u m per man gan ate
0 . 3 gm
S odi u m h ydr ox i de
0 . 6 gm
D i sti l l ed water to mak e
2 5 0 ml
Meth od :
1 . Heat 1 8 0 ml water to 2 0 ° C.
2 . A dd potas si u m per man gan ate, wh en di ssol ved .
3 . A dd th e S odi u m h ydr ox i de .
4 . A dd wa ter to make 2 5 0 ml .
T o Use:
1 . D i l u te 1 ml of th e sol u ti on i n 12 5ml s of water .
2 . Pou r
15
ml
of
th e
pr epar ed
sol u ti on
i n to
a
gl ass
con tai n er .
3 . Take th e pr i n t fr om th e wash tr ay .
4 . A l l ow to dr i p for 3 0 secon ds i n to th e sol u ti on .
5 . If an y r esi du al fi x er r emai n s i n th e paper i t wi l l ch an ge
th e sol u ti on fr om pu r pl e to or an ge i n 3 0 secon ds. It
become s col ou r l es s agai n i n on e mi n u te.
100
GLOSSARY
Ac ti ni c l i g ht: L i gh t i n th e UV , vi ol et an d bl u e r egi on of the
spectr u m th at i s r equ i r ed for l i gh t -i n du ced ch emi cal r eacti on s
i n pr i n ti n g -ou t pr ocesse s to cr eat e an i mage.
Al k al i ne : Opposi t e of aci d wi th a pH gr eater th an 7 on a pH
scal e.
Anhydr o us : Fr ee fr om water .
Ar r o wr o o t:
S tar ch
made
fr om
tu ber ou s
r oots,
i n cl u di n g
potatoe s. It i s a fi n e wh i te p o wd er th at i s u sed for si z i n g an d
bi n di n g.
Bi nde r :
Th e
su bstan c e
th at
bi n ds
togeth er
t wo
or
mor e
mater i al s or ch emi cal s i n a mi x tu r e , i . e. gel ati n an d al bu men
bi n der s h ol d th e ch l or i de, di sper si n g th e si l ver ch l or i de wh i l e
adh er i n g i t to th e paper .
Br o nz i ng : Th i s des cr i bes th e sa tu r ati on poi n t of a sal t pr i n t
ex posu r e . Th e metal l i c si l ver p ar ti cl es si t so cl o se togeth er
th ey for m a l aye r on th e su r face.
Buc k l e Br ush : A test tu be, gl as s or pl asti c tu be wi th cott on
wool t wi s ted ti gh tl y i n on e en d.
Came r a L uc i da: N ot actu al l y a c amer a bu t a n o pti cal dr awi n g
ai d.
D.ma x i s th e max i mu m d en si ty r e cor ded on fi l m or paper .
D.mi n i s th e mi n i mu m d en si ty r e cor ded on fi l m or paper .
De c a-hydr ate d : C on tai n s 1 0 mol ecu l es of water .
De -i o ni z e d Wate r : Water pu r i fi ed fr om al l i n or gan i c sal ts by
an
i on
ex ch an ge
pr ocess
or
rever se
osm osi s
bu t
or gan i c
comp ou n ds ma y sti l l r emai n .
De l i que sc e nt : A bsor bs water f r o m th e ai r .
101
De -mi ne r al i z e d Wate r : S ame as d ei on i sed water .
De nsi ty : A m easu r e of l i gh t ab so r bed or tr an smi tted i n an ar ea
of an i mage. Th i s can be measu r ed by a den si tome ter . D en si ty
i s a l ogar i th mi c val u e. If on e ar ea of a n egati ve tr an smi t s
twi ce as mu ch l i gh t as an oth er th e den si ty di ffer en ce i s 0 . 3
(i . e. th e l og of 2 ) Usi n g S tep wedges th at ar e 2 1 steps wi th a
den si ty u n i ts of . 1 5 step i n ter val s gi ves a total r an ge of 3 . 1 5
den si ty u n i ts. Cou n ti n g th e n u mber of steps th at ar e di sti n ct
i n th e pr i n t an d mu l ti pl yi n g th i s by th e . 1 5 den si ty i n ter val
bet ween th e step s , wi l l gi ve th e ex posu r e r an ge i n l og u n i ts.
To con ver t th i s r an ge to sto ps m u l ti pl e th e l og u n i ts by 3 . 3 .
De nsi ty R ang e : Th e di ffer en ce b et ween th e l i gh test r ecor ded
ar ea
an d
th e
dar kes t
r ecor ded
ar ea.
In
fi l m
it
r efer s
to
measu r i n g th e th i n n est par t of th e n egati ve, th en measu r i n g
th e den ses t par t of th e n egati v e an d su btr acti n g th i s val u e.
Th i s wi l l gi ve y ou th e d en si ty r a n ge.
D en si tome ter s ar e u se d
to accu r atel y mea su r e den si ty.
Di sti l l e d wate r : A l l i m pu r i ti es a r e r emoved by boi l i n g wa ter
an d con den si n g th e stea m.
Effl o r e sc e nt : L ose moi stu r e.
E xo the r mi c : Cr eate h eat wh en di s sol vi n g .
Fadi ng : D eter i or ati on of th e sal t pr i n t th r ou gh poor fi x i n g,
i n compl ete wa sh i n g ou t o f fi x er s an d ai r bor n e c on tami n ati on
attr i bu te to fadi n g.
Fi xe r :
u sed
A mmon i u m th i o su l fate a n d sodi u m th i o su l ph ate ar e
to
r em ove
th e
u n ex pose d
an d
th er efor e
sti l l
l i gh t
sen si ti ve si l ver sal ts.
Fo g : Non -i mage si l ver th at sh ows as di scol ou r ati on , u su al l y
cr eated by con tami n at i on or ex posu r e on th e l i gh t sen si ti ve
su r face befor e pl aced u n der a n egati ve for pr i n ti n g.
102
Ge l ati n: A pr otei n bi n der cr eated fr om an i mal h i des, bon es
an d ti ssu e s. It i s an i m por tan t bi n der i n ph o togr aph y an d
si z i n g i n paper maki n g. V ar i ou s gr ades ar e ava i l abl e.
L*a .b . CIE 1 9 7 6 L*a . b . i s based di r ectl y on th e C IE 1 9 3 1 X YZ
col ou r space. It i s a l i n ear per cepti bi l i ty of col o u r di ffer en ces.
Th e n on l i n ear r el ati on s for L * a . an d b . ar e i n ten ded t o mi mi c
th e
n on l i n ear
r espon se
of
th e
eye.
L*
for
l i gh tn ess,
a.
r epr esen ts h o w r ed or gr een th e col ou r i s an d b . r epr esen ts
h ow bl u e or yel l o w i t i s.
E ver y col ou r h as an L * a . b. val u e.
S pectr oph oto meter s
L *a. b.
gi v e
n u mber s
for
a
par ti cu l ar
col ou r .
Late n t I mag e : A n i n vi si bl e i mage for med on sen si ti se d fi l m or
paper
by
ex po su r e
to
l i gh t.
Th e
ex posu r e
cr eates
smal l
cl u ster s of si l ver at om s i n si l ver h al i de cr ystal s th at ar e i mage
for mi n g wi th ch e mi cal devel o pme n t.
Lati t ude :
Th e
ac ceptabl e
r an ge
of
an
i mage
befor e
over -
ex posu r e an d u n der -ex posu r e cau se l oss o f detai l .
Li nte r s: Fi br es u se d to mak e cotton paper . Th ese ar e th e
sh or ter fi br es l eft af ter th e c otton h as gon e th r ou gh th e
gi n n i n g mach i n e. Th e l on ger fi bres ar e made i n to th r ead.
M e asl e s: B l otch y l i gh t mar ks c au sed by i n su ffi ci en t si l ver ;
al so a ter m u sed t o de scr i be da r k mar ks made fr o m po or or
ex h au sted fi x i n g bath .
M o no -hydr ate d : C on tai n s on e m o l ecu l e of water .
M S DS :
M ater i al s
descr i pti on
of
S afety
th e
D ata
S h eet s.
ch e mi cal s,
safe
Th e se
pr ovi de
h an dl i n g,
a
fu l l
pr otecti on
r equ i r ed an d fi r st -ai d tr eatmen t.
Oxi dati o n: Th e r e moval of an e l ectr on or el ec tr on s fr o m an
atom or a mol e cu l e .
P ho to c he mi c al Ac tio n : A ch an ge can on l y b e ma de by l i gh t
th at i s abs or bed. Th e a mou n t of ph ot och emi cal ch an ge i s
103
pr opor ti on ate t o th e l i gh t i n te n si ty mu l ti pl i ed by ti me of
i l l u mi n a ti on .
P ho to l ysi s: In th e sal t pr i n t i t is th e acti vi ty cr eate d by th e
ex posu r e to l i gh t th at ch an ges th e si l ver ch l or i de to metal l i c
si l ver .
P ur i fi e d
Wate r :
Th i s
gen er al l y
mean s
water
pu r i fi ed
for
h u man con su mpti on wh i ch sti l l may con tai n sal ts an d or gan i c
matter .
P yr o g al lo l : A n or gani c devel oper agen t for ph otogr aph i c fi l ms.
Oth er
n ames
u sed
ar e
pyr ogal l ol ,
pyr ogal l i c
aci d
or
tr i h ydr ox yben z en e. It offer s an ex cepti on al ton al r an ge an d
i n cr ease s h i gh l i gh t separ ati on . Pr yo i s tox i c.
R ag : Th ese ar e ol d r a gs or n ew off -cu t s of cotton fabr i c th at
ar e br oken do wn to mak e paper . R ag th r eads or i gi n al l y c ame
fr om th e l on ger , str on ger fi br es of th e cott on pl an t . A l th ou gh
today, paper i s n ot often mad e fr om th e r ags . H o wever th ey do
make a ver y str on g pa per .
R ati o : Th e r el ati on sh i p bet ween two qu an ti ti es. F or ex ampl e
1 : 3 mean s on e par t water an d th r ee par ts ch emi cal .
R e duc ti o n: Th e a ddi ti on of an e l ectr on or el ectr on s fr om an
atom
or
a
mol e cu l e.
Ox i da ti on
an d
r edu cti on
occu r
si mu l tan eou sl y ; a r edu ci n g agen t i s a s u bstan ce wh i ch gi ve s
u p el ectr on s an d beco mes ox i di z ed .
R e fl e c ti o n: For smo oth su r faces th e an gl e of th e i n ci den c e i s
th e same
as th e
an gl e of r efl ecti on
occu r r i n g
wh en
l i gh t
str i kes th e su r face an d bou n ce s back a t th e same an gl e. For
oth er su r faces th e l i gh t i s r efl ec ted back at di ffer en t an gl es,
i . e. scatter ed.
R e fr ac ti o n: Wh en l i gh t pass es th ou gh on e me di u m to an oth er
a r ay i s ben t sh ar pl y at th e su r f ace bet we en th em. In a pr i n t
th i s affect s th e ap pear an ce of th e si l ver wh en th e gl o ssi er
104
al bu men r efr act s th e l i gh t . Th e pr i n t appear s dar ker i n th e
sh ado ws an d l i gh ter i n th e h i gh ligh ts th an sal ted paper pr i n ts.
S atur ate d S o l uti o ns: A ch emi cal i s added to l i qu i d u n ti l some
i t i s l eft u n di s sol ved . If th e l i qu i d can n ot abs or b or di s sol ve
an ymor e of th e ch e mi cal , i t i s sa tu r ated. A h i gh er temper atu r e
may
cau se
th e
pr opor ti on of i t
ch e mi cal
to
di ssol ve
bu t
as
it
cool s
a
may pr eci pi ta te . Potas si u m di ch r o mate i s
often u sed as a sa tu r ated sol u ti o n .
S e l f-mask i ng : Th e th i n n er ar ea of th e n egati ve al l o ws th e
si l ver ch l or i de con ver t t o metal l i c si l ver i n th e pr i n t. Th i s n o w
dar ker su r face of th e sal t th u s f or ms a „ mas k‟ . Th e ex p osi n g
l i gh t i s h el d back fr om r each i n g th e u n r edu ced si l ver ch l or i de
u n der n eath . M ean wh i l e th e r est of th e sal t pr i n t con ti n u es to
ex pose u n d er th e mor e den se par ts of th e n egati ve.
S e nsi to me tr y: Th i s seeks to e st abl i sh a r el ati on sh i p between
ex posu r e an d th e den si ty of ph ot ogr aph i c mater i al .
S i z i ng : Th e su bst an ce added t o paper to i n cr ease su r face
str en gth . It r esi sts th e pen etr ati o n of sol u ti on s i n to th e fi br es
of th e paper . Gel ati n an d star ch ar e th e most co mm on type s of
si z i n g.
S te p We dg e : Th i s i s ei th er a tr an spar en t fi l m or paper wi th
den si ty i n cr emen t s of 0 . 1 5 or 0.3 0 . A wedge of 2 1 steps wi th
den si ty u n i ts of . 1 5 step i n ter val s gi ve a total r an ge of 3 . 05
den si ty u n i ts. B y cou n ti n g th e nu mber of di sti n ct steps i n th e
pr i n t an d mu l ti pl yi n g by th e . 15 den si ty i n ter val between th e
steps
gi ve s
th e
ex po su r e
r an ge
in
l ogar i th mi c
u n i ts.
To
con ver t th i s r an ge t o st ops, m u l ti pl y th e l og u n i ts b y 3 . 3
(Ctei n , 1 9 9 7 ). Oth er n ames:
S ee step tabl et, opti cal wedge an d tr an smi ssi on gr ey s cal e.
We tti ng Ag e nt : A pu r i fi ed deter g en t u sed i n th e fi n al wash i n g
stage of fi l m pr oces si n g , cau si n g to water r u n s to off even l y ,
th u s r edu ci n g r u n mar ks an d wat er spots.
105
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P r oc esses, D el mar , New Yor k.
Jen kyn - Jon es, B . (1 9 8 8 ) Un i ver si ty of Ox for d.
Jon es, B . E . (1 97 4 ) Enc yc l opa ed i a of P h otogr a p h y, A r n o Pr ess
In c. , US A .
L avedr i n e, B . (2 0 03 ) A G ui d e to t he P r even ta ti ve C on ser va ti on
of P h otogr a p h ic C ol l ec ti on s, Th e Getty C on ser vati on
In sti tu te, L os A n gel es US A .
Nel son , M . I. (2 00 4 ) P r ec i si on Di gita l Nega ti ves: For Si l ver &
Oth er Al ter n a ti ve P r oc esses, M ar k I Nel son .
R ei l l y, J. M . (1 9 80 ) Th e Al b u men & Sa l te d P ap er Book : Th e
H i stor y a nd pr a c ti c e of p h otogra ph i c pr i n tin g, 1 84 0 1 8 95 . , L i gh t Impr essi on s C or por ati on . , R och ester , US A .
R ei l l y, J. M . an d K en n edy, N. (19 84 ) P h otogr ap h i c Sc i en c e a nd
En gi n eer i n g. Vol . 2 8 , Nu m. 4 , 2 8 , p. 1 6 6 -7 1.
S ch aaf, L . J. (1 9 96 ) Rec or d s of th e Da wn of P h otogr a ph y
T a l b ot' s Noteb ook s P & Q, Un i ver si ty Pr ess Ca mbr i dge,
Cambr i dge Gr eat B r i tai n .
S ch aaf, L . J. (2 0 00 ) Th e P h otogr aph i c Ar t of Wi ll i a m H enr y Fox
T a l b ot, Pr i n ceton Un i ver si ty Pr ess, Ox for dsh i r e, UK .
Tu r n er , S. (19 9 8 ) T h e Book of Fi n e P a p er s, Th ames an d Hu dson
In c, Ne w Yor k.
Wal l , E . J. an d Jor dan , F. I. (1 97 5 ) P h otogr a p hi c Fac ts a nd
For mu l a s, A mer i can Ph otogr aph i c B ook Pu bl i sh i n g Co. ,
In c. , New Yor k US A .
Wal l s, H. J. an d A ttr i dge, G. G. (19 7 7 ) Ba si c Ph oto Sc i en c e, h ow
p h otogr a p h y wor k s, Focal Pr ess, L on don .
War e, M . J. (19 94 ) Mec ha n i sm of Ima ge Deter i or a ti on i n Ear l y
P h otogr a p h s - th e sen si ti vi ty to Ligh t of WH F T a lb ot' s
106
h a l i d e - fix ed I ma ges 1 8 34 - 18 44 , Sci en ce M u seu m an d
Nati on al M u seu m of Ph otogr aph y, Fi l m & Tel evi si on ,
B r adfor d, L on don .
War e, M . J. (20 03 ) H i stor y of P h otogr a p h y, 27, 35 -3 9 .
War e, M . J. (20 06 . ) G ol d i n Ph otogr a p h y., ffotoffi l m pu bl i sh i n g,
B r i gh ton , UK .
Webb, R . an d R eed, M . (2 0 00 ) Al ter n a ti ve Ph otogr a p hi c
P r oc esses : A Wor k i n g G u i d e for Ima ge Ma k er s, S i l ver
Pi x el Pr ess, R och ester N Y US A .
107
A T T A C H M E N T 1 CD: M I S C E L L A N E A P H O T O GE N IC A
108
A T T A C H M E N T 2 T H E S A L T P R IN T M A N U A L
109
MECHANISMS OF CONTROLLING COLOUR AND AESTHETIC
APPEARANCE OF THE PHOTOGRAPHIC SALT PRINT.
Eleanor (Ellie) Young
A thesis submitted in fulfilment of the requirements for
the degree of Master of Applied Science (Photography)
School of Applied Sciences
Portfolio of Science Engineering and Technology
RMIT University
February 2008
The following images are a pictorial
illustration of the results of the research carried out in the attached thesis
An exhibition of many of these works are displayed at Photospace 34 Dight
Street Collingwood Victoria
from the 27th of February to the 22nd of March
All work was photographed on an 8 x 10 camera using FP4 black and white negative
film and PMK developer . Each of the images are contact printed using various,
formulas, binders, papers and toning methods to illustrate the different colours and
effects that can be achieved.
Exhibition Title: Miscellanea Photogenica
Miscellanea Photogenica
Title: Chinese Lantern#1
Paper: Bergger COT 320 gsm
Solution: Ammonia Chloride, Sodium Citrate
and gelatine
Toner : Gold borax and platinum
Title: Chinese Lantern #2
Paper: Saunders HP 120 gsm
Solution: Arrowroot
Toner: Gold borax and palladium
Miscellanea Photogenica
Title: Love in the mist #1
Paper: Talbot 240 gsm
Solution: Sodium Chloride and Gelatin
Toner: Gold acetate and palladium
Title: Love in the Mist #2
Paper: Talbot 240 gsm
Solution: Ammonium chloride and gelatin
Toner: Platinum
Miscellanea Photogenica
Title: Love in the Mist #3
Paper: Arches Platine HP 310 gsm
Solution: Sodium Chloride and gelatin
Toner: Gold borax and platinum
Title: Love in the Mist #4
Paper: Buxton 240 gsm
Solution: Albumen
Toner: Gold acetate and palladium
Miscellanea Photogenica
Title: Scotch thistle # 3
Paper: Berrger 320 COT
Solution: Ammonium Chloride sodium
citrate and gelatin
Toner: Gold borax
Title: Scotch thistle # 1
Paper: Berrger 320 COT
Solution: Ammonium Chloride sodium
citrate and gelatin
Toner: Gold borax
Title: Scotch thistle # 2
Paper: Berrger 320 COT
Solution: Ammonium Chloride sodium
citrate and gelatin
Toner: Gold borax
Miscellanea Photogenica
Title: Gum Leaves
Paper: Berrger 320 COT
Solution: Ammonium Chloride sodium
citrate and gelatin
Toner: Gold borax and platinum
Title: Daisy Face
Paper: Berrger 320 COT
Solution: Ammonium Chloride and gelatin
Toner: Gold borax and platinum
Miscellanea Photogenica
Title: Snail
Paper: Saunders HP 140 gsm
Solution: Arrowroot
Toner: Gold Acetate and pallatinum
Title: Shell #3
Paper: Arches Platine 310 HP
Solution: Sodium chloride
Toner: Gold Thiocyanate (No 2)
Miscellanea Photogenica
Title: Shell #1
Paper: Berrger 320 COT
Solution: Ammonium Chloride and gelatin
Toner: Gold acetate and platinum
Title: Shell #2
Paper: Berrger 320 COT
Solution: Ammonium Chloride and gelatin
Toner: Gold thiocyanate (no1)
Miscellanea Photogenica
Title: Wing #1
Paper: Arches platine 310 HP
Solution: Arrowroot
Toner: Gold acetate and palladium
Title: Wing #2
Paper: Fabriano artistico
Solution: Albumen
Toner: Gold thiocyanate
Miscellanea Photogenica
Title: Wing #3
Paper: Arches platine 310 HP
Solution: Albumen
Toner: Gold Borax
Title: Wing #4
Paper: Saunders HP 140gsm
Solution: Arrowroot
Toner: Gold acetate and platinum
Miscellanea Photogenica
Title: Pear
Paper: Buxton 240
Solution: Albumen
Toner: Gold Borax
Title: Strawberry
Paper: Fabriano Artistcio
Solution: Arrowroot
Toner: Gold Acetate and platinum
Miscellanea Photogenica
End
SALT PRINTING
MANUAL
SALT
&
ALBUMEN
P HOTOGRAPHIC P RINT P ROCESS ES
BY
E LLIE Y OUNG
THE SALT PRINTING MANUAL
A G UIDE TO S ALT AND A LBUMEN
P HOTOGRAPHIC P RINT P ROCESSES
g ol d s t re e t st u d io s
7 0 0 J a me s L a n e V i c t o ria 3 4 5 8 A u s t ra l ia
P hon e 6 1 3 5 4 2 4 1 8 3 5 • Fa x 6 0 3 5 4 2 4 1 8 3 5
w w w. g o l ds t ree t s t ud ios . co m .a u
The author and publisher of this manual deny any liability for any
consequent injury, sickness, damages or loss from using the
information contained within this text
CONTENTS
A C K N O W L E D G E M E N T S ................................................................ .............. V
I N T R O D U C T I O N ................................................................ ..................... V I
1.
T HE O RI GIN S ............................................................................. 1
2.
P HO T OGR A P HI C PR OC E S S ES ........................................................ 4
A L T E R N A T I V E P H O T O G R A P H I C P R O C E S S E S ................................ ...................... 4
P H O T O G R A P H I C P R I N T P R O C E S S E S . ................................ .............................. 4
M A T T E R S U N I Q U E T O S A L T P R I N T I N G ................................ ........................... 6
3.
PR E PA RIN G FO R SA L T P RIN TIN G .................................................. 8
T H E W O R K I N G S P A C E : ................................................................ ............. 8
E Q U I P M E N T : ................................................................ ......................... 8
T O O L S A N D M A T E R I A L S ................................................................ ............ 9
C H E M I C A L S ................................................................ ........................ 10
O V E R V I E W O F T H E S A L T P R I N T I N G S T E P S ................................ ..................... 11
4.
T HE S A LT A N D S I LV ER F ORM UL A S ............................................... 13
S o dium Ch lo ri de F o r m ul a. .............................................................. 13
Am m o n ium Ch lo ri de Fo r mula. ................................ ......................... 13
V A R I A T I O N S T O S A L T F O R M U L A S ...............................................................
A D D I T I V E S T O S A L T F O R M U L A S ................................................................ .
S O D I U M C I T R A T E ................................................................ .................
S o dium o r Am m o ni um C hlo ride + S odi um Ci tr ate ..............................
14
15
15
16
P O T A S S I U M D I C H R O M A T E ................................................................ ....... 16
Po ta ss ium D ic h ro m at e 5 % S o lut ion ................................ ................. 17
S o dium o r Am m o ni um C h lo ride + Pot as s ium Dic hrom ate ................... 17
B I N D E R S ................................ ................................ ............................ 17
G E L A T I N B I N D E R ................................................................ .................. 18
S o dium o r am m o nium c h lor ide so lut ion + ge lat in ............................. 18
A R R O W R O O T B I N D E R ................................................................ ............ 19
Ar ro w ro o t fo rm u la ................................................................ ........ 19
A L B U M E N B I N D E R ................................................................ ................ 20
Albu m en fo rm u la ................................................................ ........... 21
S I L V E R N I T R A T E S E N S I T I S E R ................................................................ ..... 22
S ilv er N it ra te S en s iti s in g Fo rmu la ................................ ................... 23
S ilv er N it ra te Fo rm u la w ith Ci t ric Ac id ................................ ............ 25
5.
T HE P A P ER ............................................................................... 26
P A P E R M A N U F A C T U R I N G ................................................................ ........
A D D I T I V E S T O P A P E R ................................................................ .............
S U R F A C E F I N I S H I N G ................................................................ ..............
W E I G H T A N D D E N S I T Y ................................................................ ...........
26
27
28
28
ii
C A R E O F P A P E R ................................................................ ...................
P A P E R S F O R S A L T P R I N T I N G : ................................................................ ....
A D D I N G S I Z I N G T O P A P E R ................................................................ .......
Ge lati n S iz ing ................................................................ ...............
29
29
32
32
H A R D E N I N G T H E G E L A T I N S I Z I N G : ............................................................. 33
Gl yo xal Ha rden ing Fo rm ula ............................................................ 34
6.
CO A TIN G TH E P A P ER ................................................................. 35
P R E P A R I N G T H E P A P E R ................................................................ ...........
C O A T I N G L I G H T W E I G H T P A P E R S A N D F A B R I C : ................................ ...............
S A L T C O A T I N G ................................................................ ....................
A L B U M E N C O A T I N G ................................................................ ..............
S E N S I T I S I N G T H E P A P E R ................................................................ .........
S E N S I T I S I N G A L B U M E N P A P E R ................................................................ ..
S E N S I T I S I N G A R R O W R O O T P A P E R ..............................................................
7.
36
36
37
39
40
41
42
P HO T OGR AM S AN D T H E N E GA T IV E .............................................. 43
P H O T O G R A M S ................................................................ .....................
T H E S A L T P R I N T N E G A T I V E ................................................................ ......
T Y P E S O F N E G A T I V E S : ................................................................ ............
A N A L O G U E C O N T I N U O U S T O N E F I L M N E G A T I V E S ................................ ...........
PM K D eve lo pe r ................................................................ ..............
43
44
45
45
46
I N C R E A S I N G T H E T O N A L R A N G E P O S T D E V E L O P M E N T ................................ ....... 48
E N L A R G I N G N E G A T I V E S I N T H E D A R K R O O M ................................ ................... 48
D I G I T A L N E G A T I V E S ................................................................ .............. 49
8.
EX P OS IN G T H E PR IN T ................................................................ 53
E X P O S U R E T I M E S ................................................................ ..................
R E C I P R O C I T Y F A I L U R E ................................................................ ............
S E L F M A S K I N G ................................................................ ....................
B R O N Z I N G ................................ .........................................................
9.
55
55
56
56
PR OC E S S IN G TH E P RIN T ............................................................. 59
P R E - W A S H ................................ ......................................................... 60
T O N I N G ................................ ............................................................ 61
Go l d B o rax To ne r ................................................................ .......... 62
S o dium Ac et ate Go ld To ner . .......................................................... 62
Th io c ya nate Go ld To n e r 1. .............................................................. 63
Th io c ya nate Go ld To n e r 2 ............................................................... 63
Pall adi um To ne r ................................................................ ............ 65
T H E F I X E R ................................ .......................................................... 67
Fi xe r ................................ ............................................................ 68
Ko dak F ixe r Te st S o lu tio n F T 1 ......................................................... 69
W A S H I N G T H E P R I N T ................................................................ ............. 70
iii
T H E C L E A R I N G A G E N T ................................................................ ............ 70
Cle a ring Age nt ................................................................ .............. 70
T H E F I N A L W A S H ................................................................ ................. 71
Ko dak Hy po Te st S o lut io n H T1a ................................ ....................... 72
Ko dak hyp o te st ht -2 ................................................................ ..... 73
D R Y I N G ................................ ............................................................. 74
10 .
ST OR A G E AN D F RA M IN G ............................................................ 75
S T O R A G E ................................ ................................ ........................... 75
F R A M I N G ................................ ................................ ........................... 76
11 .
PR OB L EM S ............................................................................... 79
GL OS S AR Y ........................................................................................ 82
A PP EN D IX 1 C H E M I CA L S ..................................................................... 86
S A F E T Y N O T E S ................................................................ .....................
M E A S U R I N G O U T C H E M I C A L S : ................................................................ ..
C O N V E R S I O N S O F M E A S U R E M E N T S .............................................................
C H E M I C A L S U S E D I N T H I S M A N U A L ................................ ............................
86
87
87
88
A PP EN D IX 2 M A T ERI A L SU P PL I ER S ....................................................... 96
C H E M I C A L S A N D A L T E R N A T I V E P R O C E S S K I T S ................................ ................
E X P O S U R E F R A M E S : ................................................................ ..............
S H E E T F I L M : ................................................................ .......................
G L A S S R O D C H E M I C A L S P R E A D E R S : ................................ ............................
P A P E R S U P P L I E R S : ................................................................ ................
S T E P W E D G E S ................................................................ .....................
96
96
96
96
96
97
B IB L IO GR A P HY ................................................................................. 98
iv
A C K N OW L ED G EM E NT S
M a n y peo p le ha v e c on t ri b u t e d t o t his m a n ua l in va r io u s wa ys .
I wo u l d li ke to m y exp res s g ra ti t u de to M ic h a el a n d Ba r ba ra
Gr ey fo r t he in i tia l i n t r od u c t ion to sa l t p rin t in g in 1 9 9 9 .
Als o wi s h t o t ha n k a n d a c kn o wl e dge A sso cia t e P r ofe ss o r Ga le
Sp r in g , P r og ra m L e a de r S cie n t if i c P ho to g ra p h y RM IT , fo r h is
a ssi st a n c e a n d t i re l ess s u pp o r t. I a m gra t ef u l t o Ala n E ll io t t
fo r hi s gen e ro u s a n d en t h us ia s t ic a ss is ta n ce a t s o ma n y l e vel s .
D r M ic ha el W a r e , w h ose a ssi s ta n c e a s a n on g oin g in va l ua bl e
con s ul ta n t wa s t r ul y a p p re cia t ed . I a l s o a m d ee pl y g ra tef ul to
P hi li p F ra n ce s o f t he RM IT P h ys i cs De pa r t men t , J a me s R e ill y ,
T ris h a n d Wa r ren Si mp son o f Si m ps on G ra p h i cs , P h re d
Pe te r son Sen i o r L e c t u re r Ap p lie d Sc ie n ce P ho t og ra p h y R M I T
a n d L u t he r H u be r o f B on d I ma gi n g fo r t he g en e r o us
sp on s o rs hi p o f t h e D u ra clea r (K o da k ) Ne ga ti ves . D a n i elle
Ed wa r ds t he “ ma n ua l ” p h o to g ra p h e r. T ha n ks t o A n t h on y
M o u rn a in of P ho t o Fo r m ula r y , S u za n n e G reg o r y a n d Ro be r t
L ove fo r t hei r a ssi s t a n ce wi t h t h is ma n u a l .
I a m in de b te d t o a ll t he s t u den ts wh o ha v e a t ten de d m y
wo r k s h op s; t h ei r q ue r ies h el pe d e x ten d m y kn o wl ed ge of t he
p ro ce ss . A la n , m y so ul - ma te a n d li fe t i me pa r tn e r , t ha n ks fo r
t he en d less s u p p o r t a n d j us t be in g t he r e.
v
I N TR O D U C TI O N
T he sa l t p rin t i s t h e f o un da ti on of p ho t og ra p h y. M y in t e res t
in t h is p r o ces s wa s in i tia t ed b y a sa l t p rin t in g wo r k s h op in
M el bo u rn e, A us t ra l i a , r u n b y M i c ha e l G r ey , t h en c u ra t o r of t he
Fox Ta l bo t M us e u m in L a c oc k , En g la n d. Wi ll ia m H en r y Fox
Ta l bo t , kn o wn a s t h e “fa t he r ” o f p h o to g ra p h y , di sc o ve re d t he
sa l t p r in t p r o cess i n 1 8 3 4 . T he h is t o r y o f Ta l b o t is q ui te
re ma r ka b le . Hi s ea rl y d is co ve r ies we r e t he f o un da ti on o f
n u me r o us p ho t og ra p hi c a n d p r in t p r oc esses , ma n y s ti ll
p ra c tis ed t oda y .
Sa l t p r in tin g is a h a n d - c oa te d t wo -s te p pr o ces s . F i rs t , t h e
sa l t so l u ti on is a p pl ie d t o t h e pa pe r a n d a l lo we d t o d r y . N ex t
is t h e sen s i ti sin g st ep , a sil ve r n i t ra t e sol u t ion , is a p pl ie d to
t he pa pe r t o f o r m li gh t s en s it iv e si lve r c hl o ri de . Ex po s u re t o
lig h t c ha n g es t he si lve r c hl o ri de to t he i ma ge ma k in g me ta l li c
sil ve r . T hi s sa me p r oc ess o c c u rs in a l b u men p rin t in g . A l b u men
ha d a n en o r m o us i m pa c t on p h o to g ra p h y b ec o m in g t he
me d i u m o f c h oi ce d u ri n g t he la s t ha lf o f t he 1 9 t h c en t u r y.
Wh il e of ten t rea t ed a s a di ffe r en t p r oc e ss , a n a l b u m en p r in t is
essen t ia l ly a sa l te d pa pe r p r in t usin g t h e a lb u m en a s a b in d er .
D ue t o t he in he ren t ma sk in g a bi li t y n o ot h e r p h o to g ra p hi c
p rin t p ro ce ss ca n c r ea t e t he t on a l ra n ge o f t h e sa l t p rin t . T he
c ha l len ge is to c rea te n e ga ti ves t ha t re a c h t his e xt r a o r din a r y
ra n ge . T he sa l t p ri n t a l so o ffe r s fl exi b il it y in co n tr ol lin g t h e
co lo u r , ton e s a n d h ue s.
Ex ce p t wh e re s ta t e d, a ll t he
me t h o ds , fo r m u la s a n d p r o ce d u res ha v e
been te s te d b y t he a u t h o r. U l t i ma te l y t h e
in t en ti on of t h is ma n ua l is to p ro vi de a
re so u r ce t ha t wi ll e n co u ra ge f u r t h er
exp lo ra t ion of sa l t p rin t in g .
vi
C HAPTER
1
1. T H E O RIG I NS
S i nc e A r is to tl e 1 (3 8 4 -3 2 2 B C) t he re is e v i de n ce t h a t me n a n d
w o me n h a v e be e n e x p lo r i ng t he re l a t io ns h i p be tw ee n l ig h t a n d
c he m i c a ls . Re m a r k a b l y i t to o k u n t i l 1 8 3 4 b e fo r e W i l l i a m He nr y
Fo x T a l bo t d is co v e r e d t he pro c es s o f pe r m a ne n t ch e m i c a l ly
p ro d uc e d i m ag es cr e at e d b y l ig h t . H is s a l te d - p a pe r p ri n ts w ere
t he f irs t p ho to g r a p h i c p ro ces s t h a t cr e at e d a po s i t i ve i m ag e
fro m a n eg a t i ve . T a l bo t ‟s „ p ho to g e n i c dr aw i ngs ‟ a n d h is
co n t i nu a l
d is co ve r ies
had
a
p ro fo u n d
effect
on
both
p ho to g r a p hy a n d t h e d e ve lo p me n t o f pr i n t m a k in g.
Wil lia m Hen r y F ox Ta l bo t ( 1 8 0 0 - 1 8 7 0) ca me f ro m a p ri vi le ged
ba c kg r o un d . He wa s wel l e d u ca te d , wi t h a b r il lia n t m in d a n d
c u ri o us a b o u t t he wo rl d a r o un d hi m . F o r t un a te ly f o r t he
hi s to r ia n s a n d p h o to g ra p hi c resea r c h er s Ta l b ot do c u m e n te d
m os t o f h is ex pe r i m en t s. 2
In I ta ly 1 8 3 3 , Ta l b ot wa s on h ol ida y wi t h hi s n e w wif e a n d
fa mi ly m e m be rs . H e be ca me f r us t ra te d wi t h h is in a b il i t y to
ske t c h on pa pe r 3. E v en wi t h t he a i d o f h is d ra win g in s t r u m e n t ,
a ca m e ra l u ci da , he c o ul d n o t ca p t u re t he b ea u t y
of
Lake
C o mo .
U ti li sin g
hi s
kn o wl e dge
of
c he m is t r y he p on d e re d wa y s o f “ fi xin g ” a n i m a ge
on pa pe r . B y s p r i n g 1 8 3 4 Ta lb o t ‟s pon de r in g s
be ca me r ea l i ty . He fo un d t he ra ti o b et we en s a l t
a n d s il ve r n i t ra te t ha t wa s
essen t ia l
to
c rea te
and
„s ta bi li se ‟
an
i ma ge.
Ta l bo t ‟s dis c ov er y of t he
sa l t p rin t in s pi re d yea r s of
re sea r c h,
la yin g
t he
fo un da ti on f o r ma n y f u t u re
p ho t og ra p h ic
p rin t
p ro ce sse s . In 1 8 3 9 wi t h t he a ssi s ta n c e
1
E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r ap h y , D o v e r P u b l i c a t i o n s I n c N e w Y o r k . p 1
S c h a a f , L . J . ( 2 0 0 0 ) T h e P h o t o g r ap h i c A r t o f W i l li a m H e n r y F o x T a l bo t , P r i n c e t o n
U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K. p .2 9 .
2
3
Ibid.p13.
T he Sa l t p ri n t M a n u a l |
1
T he O rig in s
of h is c ol lea g ue , S ir J o hn He rs c he l, T a lb o t wa s a b le t o „ fix ‟
t hi s i m a ge p e r ma n e n tl y on pa pe r . D es pi te t his , i ma g e f a din g
st il l ca us e d T a l bo t a gr ea t dea l of g r ief t h ro u g h in a de q ua te
p ro ce ssin g a n d wa sh in g . Fa din g be ca me s u c h a n i ss ue fo r
ma n y sa l t p rin t e rs t ha t a fa din g co m m i t tee wa s es ta bli s he d in
1855.
T he p h o to g ra ms , o r a s Ta l bo t c a ll ed t h e m „ p ho t og e n ic
d ra wi n gs ‟ we r e c re a te d b y coa t in g wr it in g pa pe r wi t h a sa l t
(s od i u m c h lo r i de ) s ol u ti on . Af t e r t h e p a pe r d rie d he a p p li ed a
coa t in g of s il ve r n it ra t e so l u ti on . An ob je c t
su c h a s a lea f o r la ce wa s p la c ed on t he d r y ,
n o w li g h t sen s i ti v e pa pe r; a n i m a g e wa s
c rea te d wh en ex p o sed to s un li g h t. T hi s is a
sa l t p ri n t o r sa l t ed pa pe r p rin t . I n 1 8 3 4
Ta l bo t bega n ex p os i n g i m a ge s in a ca m era . B y
con ta c t p rin t in g t he se n e ga ti ve sa l t p rin t s,
Ta l bo t p ro d u ce d po si ti ve i ma ges .
In 1 8 4 0 he d is c ove r ed t h a t ga ll i c a c i d
de vel o pe d o u t a la ten t i ma ge o n pa p e r . T h is
c rea te d
t he
f i rs t
dev el op ed -o u t
n ega ti ve
to
po si ti ve
p ho t og ra p h ic p rin t p r oc ess . Ex po s u r e ti me in t he ca me ra
d ra ma t ica ll y de c rea sed f ro m h o u rs to sec on ds 4. T he e ff ec t on
p ho t og ra p h y ‟s
re p r od u c ti ve
po we r
wa s
en o r m o us
and
5
effe c t ive l y wa s t he de m ise o f t he Da g u er re o t y pe .
As ea rl y a s 1 8 4 2 Ta l bo t p r o po se d t h e t ele p h o to len s,
ele c t ron ic f la s h a n d in f ra re d p h o t og ra p h y . H e se t t h e
fo un da ti on of p h o t og ra v u re wi t h p ho t o en g ra vin g , p r e di c t in g
p ho t og ra p h ic r ep r od u c t ion wo u l d f oll o w t h e wa y o f t he
p rin t in g p re ss 6. Ta l bo t wa s o bses se d wi t h t he po we r of l ig h t .
T hi r t y- t wo o f h is f o r t y- t wo p u b li s he d p a pe rs dea l t wi t h l ig h t . 7
T he o u t st a n d in g s c ho la r, ex pe ri m en t er , t hin ke r a n d
a r ti s t wa s de s tin e d to be c o me on e of t he m os t in f l ue n ti a l
sc ien ti s ts of t he n i n e teen t h c en t u r y . Ta l bo t ca me in t o
4
E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r ap h y , D o v e r P u b l i c a t i o n s I n c N e w Y o r k . p 3 2 1
5
Ibid. p 323
S c h a a f , L . J . ( 2 0 0 0 ) T h e P h o t o g r a p h i c A r t o f W i l li am H e n r y F o x T a lbo t , P r i n c e t o n
U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K. p 2 8
6
G r a y , M . , O l l m a n , A . a n d M c C u s k e r , C . ( 2 0 0 2 ) T h e F i r s t P h o t o g r a p h s W i l li am H e n r y
F o x T a l b o t a n d t h e B i r t h o f P h o t o g r a ph y , P o w e r H o u s e B o o k s U S A , N e w Y o r k .
7
T he Sa l t p ri n t M a n u a l | T he O ri gin s
2
T he O rig in s
p ho t og ra p h y a s a pi c t u re ma k e r r a t h er t ha n a
sc ien ti s t 8 c rea tin g a n e w c ra f t a n d a r t fo r m . T he
sa l t p rin t e m b ra c es t he a r t, c ra f t a n d sc ien ce of
p ho t og ra p h y .
Sa l t p rin t in g in cl u des t h e a l b u m e n p rin t in g
p ro ce ss . Al b u m en i s t he b in de r o b ta in ed f r o m t he
egg wh i t e o f u s ua l ly hen ‟s e gg s . In bo t h s a l t a n d a l b u men
p rin t in g s i lv er c hl o ri d e f o r ms t h e i ma ge . T h e F r en c h
p ho t og ra p he r L o u i s Dés i ré B la n q ua r t -Ev ra r d d eve lo pe d t h e
a lb u m en p rin t in t he la te 1 8 4 0s . H e di sc ov e re d t he a l b u men
pa pe r wh i l e sea r c h i n g f o r i m p r ov e men ts in Ta l b o t‟ s ca l o t y pe
(p a p e r n ega t ive ) p r oc ess . O n M a y 2 7 , 1 8 5 0 B la n q ua r t -E v ra r d
p res en te d hi s di sc o ve r y to t he F r en c h Ac a d e m y . B y 1 8 5 5 m os t
p ho t og ra p he r s
ha d
c h a n ge d
to
a l b u men
p rin t in g ,
t hi s
re ma in e d t h e p rin ci pa l p rin t in g me t h od un ti l 1 8 9 0 when
gela t in si lve r ca me in t o use 9.
T he Ge r ma n ci t y of D re sd en , b y 1 8 7 0 s u p pl ie d t h e m a j o ri t y o f
t he wo r l d‟ s a l b u m en p a p e r. D res den ha d t he a d va n ta g e o f
be in g cl ose t o t h e pa pe r ma n u fa c t u r er s of Ri ve s a n d S a xes .
Co m bin ed wi t h a n e xce llen t s u p p ly of l o w c os t eg gs a n d la bo u r
t he y p r o d u ce d a su pe ri o r p r o d uc t . In 1 8 8 8 t he
D re sd en e r Al b u m u i n fa b r i ken A. G fa c t o r y use d
m o re t ha n six m il l ion eg gs to ma ke 1 8 , 6 7 4
rea m s of a l b u me n pa pe r . Ea c h ha n d c ra f te d
rea m wa s 4 8 0 s he e ts a t 4 6 0 m m b y 5 8 0 m m .
T his wa s j us t on e of se ve ra l f a c t o rie s in
D re sd en a l on e . 10
P ho t og ra p he r s to da y ma y n o t be a wa re o f ho w t he e a r ly
pi on ee r ‟s
ma de
t he i r
f i rs t
p h o to gra p h i c
i ma ges ,
but
con t e m po ra r y p h o t og ra p he rs s t il l s ha re t he sa m e de si re to
ma ke pe r m a n en t i ma ges . 11 To da y, a s p ho t og ra p h ic i ma g i n g
con t in ues to ex ten d a n d d eve lo p we de ba te a n d s t r ug gl e wit h a
m y ri a d of i ss ues of wh a t we be lie ve p ho to g ra p h y s ho u l d be .
W a l l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B as i c P h o t o S c i e n c e , h o w ph o t o g r a p h y w o r k s ,
Focal Press, London. p 13
8
E d e r , J . M . ( 1 9 7 8 ) H i s t o r y o f P h o t o g r a p h y , D o v e r P u b l i c at i o n s I n c N e w Y o r k . p 5 3 5 537
9
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p
33-35
10
W a l l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B as i c P h o t o S c i e n c e , h o w ph o t o g r ap h y w o r k s ,
Focal Press, London. p13.
11
T he Sa l t p ri n t M a n u a l | T he O ri gin s
3
C HAPTER
2
2. P H OT OG R AP H IC P R O C ES S ES
T h is c h a p t er d is c us s es a l t er n a t iv e pro c e s s es i n ge n er a l . I t lo o ks
a t t h e d i f f er en c e b etw e e n p ri n t i ng -o u t a n d pro c es s i ng - o u t
p ri n ts a n d co n c l u d e s w i th is s ues u n iq ue to t h e s a l t pr i n t .
A L TE R N A TI V E P H O T O G R A P H I C P R O C E S S E S
M a n y o f t he ea rl y p h o tog r a p h i c p rin t p r oc esse s a re re fe r re d t o
a s „ A lt e rn a ti ve ‟ . T h i s te r m a ls o i n c l u de s me t h od s of ca p t u rin g
i ma ge s wi t h len s- l ess ca m e ra s s u c h a s pin h ol e . T h e m o re
co m m on l y p ra ct i se d p ro ce sse s in c l u d e a l b u men , c ya n o t y pe ,
gu m
bi c h r o ma t es ,
g u m oi ls ,
br o m oil s,
zia t y pe ,
pla t in u m /pa lla d i u m , sa l t p rin ts a n d V a n D y ke b r o wn .
De sp i te ma n y de ba te s ov e r t he yea r s , „a l te rn a t ive ‟ i s wi de ly
un de rs t oo d a n d a c c ep te d b y t he v a s t m a jo r i t y o f p ra c t it io n er s .
Te r ms les s f re q ue n tl y u se d in cl u de ; t ra di t ion a l p ro ces ses ,
hi s to r ic a l p h o t og ra p hi c p r o ces ses , ha n d c ra f te d i ma ges a n d
p ri m i ti ve p ho t og ra p h y .
D igi ta l i ma gin g h a s la rge l y di s pla c ed f il m ca p t u r e a n d
c he m ica l p r oc ess in g. B la c k a n d wh i te silv e r gela t in p ri n tin g ,
on c e t he ma in s ta y fo r p h o to gr a p h ic p r in tin g , t o da y is
con si de re d a n a l t er n a t ive p ro ce ss .
PHOTOGRAPHIC PRINT PR OCESSES .
De ve lo pe d - o u t a n d p rin te d -o u t a re t he t wo m a j o r p h o t og ra p hi c
p rin t ca teg o ri es .
1. De ve lo pe d , o r p ro ce sse d - o u t, r efe r s t o t he i ma g e t ha t is
ca p t u re d b u t n o t s e en un ti l c h e mi ca l b a t hs „ dev el op ‟ o r
„p r o ces s ‟ o u t t h e l a ten t i ma ge , kn o wn a s t he c h e mi ca l
re d u c ti on o f si lve r pa r ti cl es . M o st p h o to g ra p hi c pa p e rs
a re p ro ce sse d in t h e da r k ro o m un de r a re d sa f e li g h t .
Sin ce 1 9 0 5 p ro ces s in g - o u t ha s been t he m os t co m m on
p ra c ti ce o f p rin t in g . 12 No w di gi ta l o u t p u t s u r pa s se s t he
t ra di t ion a l we t p r o c esses .
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y a n d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 2
12
T he Sa l t p ri n t M a n u a l |
4
D E V E L O P E D -O U T P H O TO G R AP H I C P R I N TI N G
ADVANTAGES
2.
DISADVANTAGES
Negatives can create enlarged
prints to a preferred size.
To n a l r a n g e i s n o t a s w i d e a s
some of the printing-out
processes.
Mass production standardised
coatings, allowing print
consistency.
P a p e r t yp e s a n d s u r f a c e s a r e
limited the by manufacturer‟s
choice.
Processing chemicals are in a
ready to use form.
A traditional wet darkroom is
required.
P rin t in g -o u t re fe rs to t he p r oc ess es whe r e p r in ts a re
c rea te d b y l ig h t e n e rg y on l y . T he y re q u ir e n o c he m i ca l a i d
to p ro d u ce a n i m a g e . M a n y o f t he me t a l ba se d p r o ces ses
a p pea r in s ha de s of b ro wn . T h is i s d ue t o t he i ma ge
ma k in g pa r ti cle s i ze . T he y a re to o sm a ll fo r l ig h t to
re fle c t a l l t h e wa v elen g t h s of li g h t. P r oc esse d o u t sil ve r
gela t in a p p ea rs bl a c k a s t he s il ve r pa r ti cl es a re la rge
en o ug h t o a bs o r b a l l wa ve len g t h s of li g h t .
A hin g e d b a c k p ri n tin g f r a me a ll o ws e a sy a c ce ss to c h ec k
t he ex po s u re d u ri n g p r in tin g . Fo r t h e f i rs t si xt y -f iv e yea rs
of p ho t og ra p h y t h is wa s t he m et h o d o f c re a t in g t he
ma jo r i t y of p ho t og r a p hi c p rin ts . 13
13
Ibid.p2.
T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s
5
P R I N TI N G - O U T P H O T O G R AP H I C P R O C E S S E S
ADVANTAGES
DISADVANTAGES
Th e c o a t i n g s a r e a p p l i e d b y
hand, the prints are therefore
uniquely the photographer‟s.
Restricted to contact printing, the
negative is the same size as the
print. ( An exception is the
bromoil process)
Th e t o n a l r a n g e i s g r e a t e r t h a n
developed out photographic
papers for processes such as
salt, albumen and platinum
/palladium. Some have a narrow
tonal range, but offer benefits
such as colour using pigments.
A wide choice of papers and
textures.
Contact printing requires creating
negatives either by using large
format cameras, increasing the
negative size in the darkroom or
printing inkjet negatives from
digital files.
Th e n u m e r o u s c o n t r o l s o v e r
tonal effects, contrast, surface
finish and colours.
Printing-out processes maybe one,
t wo o r m u l t i c o a t i n g s t h a t r e q u i r e
drying between each coat before
exposing or re-exposing.
A darkroom is not required.
Most solutions need to be
prepared from raw stock
chemicals. Some require care and
special handling.
Sunlight is inconsistent. For
consistency an artificial UV light
source is required.
Sunlight is a readily available
light source to expose prints.
Prints can be checked during
exposure.
Each of the processes requires a
s p e c i f i c t yp e o f n e g a t i v e .
Exposures are considerably longer
than processed out papers,
minutes to hours as opposed to
seconds.
M A T TE R S U N I Q U E TO S A L T P R I N T I N G
Sa l t P r in t in g i s a p rin t in g -o u t p ro ces s of fe r in g a ton a l r a n ge
gr ea te r t ha n a ll o t h er p h o to g ra p hi c p ri n ti n g p ro ce sse s . T h is i s
a t t ri b u te d to a n in he r en t ma s k in g a bi li t y t ha t o cc u r s d u rin g
exp os u re . I t r e q ui r es a den se n eg a t i ve wh i c h ma y ex cl u de
p rin t in g wi t h o t he r p ro ce sse s . S il ve r n i t ra te s ol u t ion res p o n ds
un fa v o u ra bl y t o ma n y pa pe r a d d i ti ves , re st r i c tin g sa l t p rin tin g
to q ua li t y 1 0 0 % c ot t on wa t e r c ol o u r pa pe rs . T wo se pa ra te
sol u t ion s a re a p pl i ed ; e a c h m us t be d rie d bef o re ex po s u re .
An y s h o r t c u ts res ul t in s ta i n in g o r p ro d u cin g a le ss t ha n
des i ra ble p rin t .
T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s
6
T he Sa l t a n d
in fl u en ce d b y :
Al b u men
p r in t
c ol o u r
and
a pp ea ra n ce
is
o
T he pa pe r : s iz in g in t he pa pe r a n d t he c ol o u r of t h e
pa pe r .
o
Ch e mi ca ls : di ff e ren t f o r m ula s a n d a d di ti ve s .
o
H u mi di t y .
o
The n ega tive or subject ma tter for photogra ms .
o
L ig h t ex po s u re s o u r ce .
o
Ton in g .
o
Wa s hin g a n d fix in g .
A p la in sa l te d p rin t ha s a s in g le la y er st r u c t u re in wh i c h t he
i ma ge is e m be d de d in t he p a p e r fi b re . An a l b u m en p rin t ,
h o we ve r, i s a t wo la ye r s t r u c t u re. Al b u men h ol ds t he i ma g e on
t he s u r fa ce of t he p a pe r . 14
T he a d d i ti on of ge la t in a s a bin de r i n t he sa l t so l u ti on ca n
a lso c rea te a t wo l a ye r s t r uc t u r e in t he sa l t p r in t. T h e g el a ti n
h ol ds t he i ma ge on t he s u r fa ce of t he p a pe r .
14
http//archive.amol.org.au/collections/1/3/17.html
T he Sa l t p ri n t M a n u a l | P ho t og ra p h ic P r oc esse s
7
C HAPTER
3
3. P R EP A RI NG
F OR
SALT
P R IN T IN G
R eq ui re m e n ts o f t h e w o rk i ng s p ac e , e q u i p me n t , m a te ri a ls a n d
c he m i c a ls r eq u ir e d fo r s a l t pr i n t i ng ar e d is c us s e d in t his
c h a p te r . I t co n c l u d es w it h a n o u t li n e o f t h e s t e ps i n vo lv e d i n
m a k i ng t he s a l t p r i n t .
C he m i c a ls t h e ms e l v es ar e no t n e ces s a r i l y d a ng ero us , b u t
m is h a n d li ng , o f te n th ro ug h i g no r a n ce c a n c a us e s er io us
i n j ur ies . T a ke t i me to u n de rs t a n d t h e c he m i c a ls yo u a re us i ng ,
ho w t he y s ho u l d b e h a n d le d a n d t re a t t he m w i t h t h e u t mo s t
res p ec t . A s k t h e c h e mi c a l s u p p li ers o r d o w n lo a d fro m t he w eb
M a t er i a ls S a f e ty D a t a S h ee t s ( M SD S) , fo r e ac h o f t h e c h e mi c a ls
a cq u ir e d. T h e M SD S gi ves a f u l l des c r i p t io n o f s a f e h a n d l i ng ,
w ha t pro t e c tio n is r eq ui re d a n d t he fi rs t ai d t re a t m e n t .
A tr a d i ti on a l we t da r k r oo m is n o t n e ces sa ry . A l t h o ug h
des i ra ble , a U V li g h t b ox i s n o t es sen ti a l a s t h e s un ca n s u p pl y
t he u l t ra v io le t (U V ) lig h t r eq u i re d to exp ose t h e p r in t . T he
c he m ica ls fo r sa l t p rin t in g a n d p r o ces sin g a re re la ti vel y
in ex pen s iv e a n d ea sil y o b ta in e d . Ho we ve r s o me c he m i ca l s fo r
to n in g a r e c on si de r a bl y m o re c os t ly .
THE WORKING SPACE:
o
Wo r k ro o m or a rea fo r coa t in g pa pe r wh e r e a l l U V a n d
sun li g h t ca n be bl o c ke d o u t . L o w in ca n des ce n t l ig h t in g
is r e q ui re d ; 2 5 t o 5 0 wa t t ( lo w wa t ta ge n o r ma l h o us e
la mp ) a t lea s t 1 . 5 m a wa y f ro m t h e wo r kin g s u r fa c e . T hi s
is wh e re coa t in g a n d in s pe c t ion wi ll ta ke p la ce . N B :
Fl uo r es cen t li g h ts s h o ul d n o t be use d a s m os t e m it U V .
o
A ben c h o r ta bl e wi t h a d r y c lea n fl a t s u rf a c e f o r coa t in g
pa pe r .
o
A we t p r o ces sin g a rea , p r efe ra b l y wi t h r un n in g wa te r ,
sepa r a t e f ro m t he c oa tin g a n d t he ex p osin g a r ea . T he r e
sh o ul d be e n o u g h s pa ce to ho l d 5 t o 8 p ro ce ssin g t ra ys.
o
A clea n , d us t f ree d r y l o ca ti on a wa y fr o m wa t e r a n d
c he m ica ls f o r d r y in g fin is he d p r in ts .
EQUIPMENT:
o
A gla s s s hee t 4 m m to 6 m m t hi c k . Si ze a p p r oxi m a tel y
4 0 0 m m x 5 0 0 m m to p ro vi de a h a r d f la t ba se fo r
coa t in g . An a l te rn a ti ve is hea v y ca r d . T his p r o te c ts t he
ben c h o r ta ble f ro m in e vi t a b le s il ve r n i t ra te s ta in s .
T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g
8
o D r yin g ca b in e t a n d/ o r ha i r d r ye r to d r y pr in ts .
o Exp os u re f ra me s. T he se ca n be t ra di t io n a l
a s t he i ma g e s ho wn , o r a p ie ce o f 3 m m or
4 m m t hi c k gla ss cl ip pe d t o a b oa r d. T he
boa r d ca n be hin ge d b y t wo pa r ts ta p ed
to ge t he r a s s h o wn . T he b oa r d a n d t he
gla s s s h o ul d be t h e sa me si ze , ha ve t he
edg es of t he gla ss g ro un d o r ta pe d t o
a vo id c u t tin g h a n d s .
o Sca les , ei t he r ba la n ce o r e le c t ron ic , m e a su r in g 0. 1 g m
o r les s.
o A r ti fi cia l U V li g h t s o u rc e o r s un .
T O O L S A N D M A TE R I A L S
o
Fo r c oa tin g: G la s s r od s 1 0 m m wi d e r t h a n t he n e ga ti ve .
Fo r exa m pl e a 2 0 3 x 2 5 5 m m ( 8 x 1 0 in c h ) n ega t ive
re q u ir es a ro d 2 1 3 m m l on g . T h ese a re m a de f r o m
a p p rox 1 m m t h ic k wa lle d g la ss t u bes wi t h 1 0 m m
op en in g. A t r ia n g u l a r s ha pe a s ill u s t ra t ed wi ll a ll o w
coa t in g wh i le us in g on e ha n d.
Al te rn a t iv el y , b r u s h es wi t h
D is po sa b le s po n ge b r us he s
a va i la ble in m u l ti pl e s i zes .
wi t h c o t ton wo o l a n d a te s t
o
n o me ta ll ic pa r ts .
a re c he a p a n d rea di ly
B u c kl e b r us he s ca n be ma de
t u be .
Sy r in g es 3 m l o r 5 m l t o a cc u ra t el y m ea s u re c oa tin g
sol u t ion s ( wi t h o u t t he n ee d le ). C he m i st s h o ps sel l t h e
sy r in ge s.
o
B ro wn gla ss b o t tl e 1 0 0 m l wi t h a wi de o pen in g f o r t h e
sil ve r n i t ra te s ol u t i on .
o
St o ra ge b o t tle s 5 0 0 m l fo r sa l t so l u ti on s.
o
Gla s s o r p la s t ic g ra d ua te s 5 0 0 m l a n d 1 0 0 0 ml
fo r ma kin g a n d m ixi n g so l ut io n s .
o
Gla s s o r p la s t ic mea su r in g g ra d ua t e o r pi pe t te s
2 5 ml a n d 5 0 m l wi t h a t lea s t 1 m l in c re men t s
o
6 t o 1 0 p ho t og ra p h ic t ra y s , la rg e r t ha n t he p r in t
si ze t o a l lo w r o o m t o m ov e t h e p r in t ea sil y .
o
Se t of wo o de n o r p l a st i c p ri n tin g t on gs .
o
Clo t h es l in e a n d p lastic pegs or non metallic clips for
hanging prints to dry, alte rn a t iv el y n on-metallic screens,
fibreglass or plastic for drying prints flat.
o
Ro lls o f a bs or b en t wh i t e pa pe r t o we ls to wi pe up s pi lls
a n d ex ces s so l u ti on .
T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g
9
o
R ub be r gl o ves fo r ha n d p ro t ec t ion . N ot t he po wd e re d
glo ve pa c ks , a s yo u ta ke t he m o ff po wd e r ma y
con ta m in a t e yo u r wo rk a n d wo r k a re a .
o
S ma l l s q ua res of pa pe r to we i g h s ma ll e r a m o un ts of
c he m ica ls .
o
Pa pe r c u ps fo r mea s u ri n g la r ge r a mo un t s of c h e mi ca ls .
o
Pla s ti c sp oon s
con ta in e rs .
o
1 0 0 % Ra g c o t ton wa te r co lo u r pa pe r si z ed wi t h ge la tin o r
sta r c h . Se e C ha p t e r 5 T he P a p er f o r m o r e in fo r m a ti on .
o
Re m ova bl e ta pe t o h ol d pa pe r s t il l wh i le c oa ti n g .
o
Ch eese cl o t h to s t ra in a l b u men a n d a r r o wr o o t s ol u t ion s .
to
r e mo ve
dry
c h e m ica ls
from
t he i r
CHEMICALS
See A p pen d ix 1 fo r m o re in fo r ma t ion o n t he f ol lo wi n g
c he m ica l s .
Sa l ti n g s ol u ti on s
o
A m m on i u m c hl o ri de .
o
A r ro wr o o t ( f o r s ta r c h bin de r / si z in g ).
o
Ci t ri c a c i d ( re q u i re d fo r A r ro wr o o t s ta r c h b in de r ).
o
Gela t in ( f o r b in de r / si zin g ) .
o
Sil ve r n i t ra t e ( s en si ti se r ).
o
So di u m c hl o ri de (sa lt ) .
o
So di u m c i t ra te ( in c r ea se s s pee d a n d m o di fie s
co lo u r ) .
o
Po ta ssi u m d ic h r o ma te ( to in c rea se c on t r a st ) .
Al b u men P rin t in g
o
Egg wh i t e .
o
Gla cia l a ce t i c a c id .
o
Is o p ro p yl Al co h ol 7 0 % ( f o r d o u bl e c oa ti n g) .
Ton in g
o
A m m on i u m t hi o c ya n a te .
o
Ci t ri c a c i d .
o
Gol d c hl o ri de 1% .
o
Po ta ssi u m c h lo r op la tin i te 2 0% .
T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g
1 0
o
So di u m a ce ta t e .
o
So di u m c hl o ri de .
o
So di u m c hl o ro pa lla di te 1 5 % .
o
So di u m te t ra b o ra te ( bo ra x ) .
o
So di u m t h io c ya n a te .
P ro ce ssin g
o
So di u m ca r bon a t e ( a d di ti ve to fix e r) .
o
So di u m s ul p hi te (f ix er clea r in g a gen t ) .
o
So di u m t h ios u lf a t e “ h yp o ” (f ixe r ) .
D is ti lle d o r de - min era li ze d wa te r s h o ul d be use d to m i x a ll
coa t in g a n d ton in g sol u t ion s. C on d i ti o n of p i pes a n d pl u m bin g
fix t u re s ma y a l lo w th e wa te r t o p ic k up t ra ce ele m en ts th a t
a ffe c t t he c he m ic a l r ea c t ion s d u rin g t he p rin t c oa tin g a n d
to n in g p r o cess es . A lt h o ug h t h e q u a li t y of ta p wa te r ca n v a r y
gr ea tl y i t is gen e ra ll y s ui ta bl e fo r ma kin g t h e fixe r , s ta n da r d
wa s hin g a n d rin sin g o f p r in ts .
O V E R V I E W O F TH E S A L T P R I N TI N G S T E P S
Th e f ol lo win g l is t gi ves a ba si c
in v ol ve d in ma kin g a sa l t p r in t .
ove r vi e w
of
t he
st ep s
1.
M a ke t he sa l t so l u ti on .
2.
U se 1 0 0 % c o t to n ra g pa p e r a n d ma r k o u t t he i ma ge a rea .
3.
A pp l y t h e s a l t s ol u t ion to t he pa pe r.
4.
D r y t he sa l t ed pa pe r .
5.
M a ke t he s en si t ise r .
6.
Sen s i ti ze t he p a p e r in s ub d ue d l ig h t .
7.
D r y in s u b d ue d li g h t .
8.
Pla ce n e ga ti ve a n d sec u re in p r in tin g fra m e in s u b d ue d
lig h t .
9.
Exp ose t o U V li g ht .
1 0 . Re m ove p rin t f r o m f ra me in s u bd u ed lig h t .
1 1 . P ro ce ss in s u b d ue d lig h t .
T he s te ps
in c l u de:
in vo lv e d
in
p r o ces sin g
t he
ex p ose d
sa l t
p rin t
1 . P re – wa s h in ta p wa te r in s u b d ue d l ig h t .
T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g
1 1
2 . Wa s h in ta p wa t e r i n s u b d ue d li g h t .
3 . Ton e in s ub d u ed lig h t .
4 . Wa s h in ta p wa t e r i n s u b d ue d li g h t .
5 . Fix b a t h s.
6 . Wa s h in ta p wa t e r.
7 . Hy p o c lea ri n g ba t h .
8 . Fin a l wa s h in ta p w a te r .
9. Dry.
T he Sa l t p ri n t M a n u a l | P re pa rin g f o r S a lt p rin t in g
1 2
C HAPTER
4
4. T H E S A LT
AN D
S IL V E R F OR MU LAS
T he b as i c fo r m u l as a re s e t o u t i n t h is c h a p te r , w i t h a n u m b er
o f v a ri a t io ns i n c l u d i ng b i n d ers . E a c h c h a ng e o r v ar i a t io n w il l
cr e a te a d i f fer e n ce , in s o m e c as es d r a m a t i c d i f f er e nc es w i ll b e
o bs er ve d . T hes e a r e t he f irs t s te ps i n co n t ro l li n g t h e co l o ur ,
to n a l r a ng e a n d t he a es t h e t i c a p p e ar a n c e o f t he s a l t p r i n t.
Ta l bo t u se d so di u m c hl o ri de , o r co m m on ta b le sa l t in his fi rs t
sa l te d pa pe r p r in t s. M os t ta ble sa lt s to da y ha ve a t l ea s t
so di u m a l u m in o si li ca t e a n d pos si b ly so d i u m io di de . T he se
a d di t ive s ma y rea c t wi t h t h e s il ve r n i t ra te , c rea t in g c h e m ica l
fog gin g re d u cin g p r in t q u a li t y . P u r c ha se t he s o di u m c h lo r id e
fr o m t he l oc a l c h e m ica l s u pp li e r .
Ple a se No t e: T he sa l t so l u ti on s ( c hl o ri des ) a re n o t li gh t
sen si t iv e a n d la s t i n de fin it el y . Al l sa l t , a lb u men a n d a r r o wr oo t
sol u t ion s ca n be ma de un de r n o r ma l li g h tin g c on di t ion s
SODIUM CHLORIDE FORMULA.
D is ti lle d Wa t e r
So di u m c hl o ri de
2 5 0 ml
5 gm
M et h o d:
1 . A t r oo m te m pe ra t u re a dd s od i u m c h l o ri de t o t h e di s ti ll ed
wa t er .
2 . T his wil l di sso lv e ea si ly a n d is r ea d y f o r us e wh en
di sso lv ed .
AMMONIUM CHLORIDE FORMULA.
D is ti lle d Wa t e r
A m m on i u m c hl o ri de
2 5 0 ml
5 gm
M et h o d:
1 . A t ro o m te m pe ra t u re
di s til le d wa te r .
add
a m m on i u m
c hl o ri de
to
T he Sa l t p ri n t M a n u a l |
the
1 3
2 . T his wil l di sso lv e
di sso lv ed .
ea si ly
and
is
r ea d y
for
us e
wh en
T he di ff e ren ce s b e t we en t he a m m on i u m c h lo r id e s ol u t ion a n d
t he s o di u m c hl o ri d e sol u t ion ; A m m on iu m c hl o ri d e sol u t ion
wi l l sli g h tl y d ec r ea se exp os u r e ti m e , en r ic h t he co lo u r a n d
con t ra s t o f t h e p r in t m o re t ha n t he s o di u m c h lo r id e so l u t ion .
So di u m c hl o ri de is sli g h tl y re dd e r in c ol o u r.
V A R I A TI O N S T O S A L T F O R M U L AS
Sa l t p rin t s a re a t t h ei r b es t wh e n t he c hl o ri d e ( sa l t ) c on te n t i s
a p p rox i ma te l y 2 % a n d t he si lve r s o lu t ion is ro un d 1 2 %.
Cha n ge s to t h e ra ti o o f sa l t to si lv er c a n be use d t o a l te r t he
to n e a n d t he co lo u r of t he fin a l p rin t . Bo t h t h e s od iu m
c hl o ri de a n d a m mo n i u m c hl o ri de a r e t he ba se f o r m u la s fo r t he
fol lo win g va ria t ion s .
Inc re a se Sal t P e rc e nt ag e : Ta l bo t
sa l t in t he s ol u ti o n , t he pa p e r
T his wa s h is fi r s t a t te m p t a t
i ma ge s. 15 Ef fe c ts o f in c re a s in g
sol u t ion ;
fo u n d t ha t b y in c rea s in g t he
be ca me le ss li g h t sen s it iv e .
s ta b il isin g or “ f i xin g ” t he
sa lt p er cen ta ge in t h e sa lt
o
3 % c rea tes a s li g h t de c rea se in con t ra st a n d t he t on es
a re co ol e r .
o
5 % c rea te s a d ec r ea se i n con t ra s t a n d t he i ma ge a p p ea rs
fla t .
o
1 0 % c rea te s a s u bs ta n t ia l d ec r ea se
re s ul tin g in a ve r y f la t we a k p r in t.
in
the
con t ra s t
De c r e a se
Sal t
P e rc en t ag e :
Ta l bo t
dis co ve re d
t ha t
by
de c rea s in g t h e sa l t t he re wa s a n in c r ea se in l ig h t se n s i ti vi t y. 16
Ho we ve r , de c rea sin g t h e c h lo r i de s ol u ti on be lo w 1 % ten d s t o
p ro d u ce p rin ts la c k in g b r il lia n ce a n d d en si t y .
Ef fe c t s of
de c rea s in g t he sa l t in t he s ol u t io n t o;
o
1 % ca use s t he sa l t s ol u ti on t o in c re a se t he c on t ra s t a n d
t he ton es be co m e wa r me r in c ol o u r.
S c h a a f , L . J . ( 2 0 0 0 ) T h e P h o t o g r a p h i c A r t o f W i l li am H e n r y F o x T a lbo t , P r i n c e t o n
U n i v e r s i t y P r e s s , O x f o r d s h i r e , U K.
15
16
Ibid.p19
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 4
o
0 . 5% ca us es t he sa l t s ol u ti on to fu r t h e r in c rea s e
con t ra s t, i t be c o m e a wa r m e r co lo u r a n d l ose s s o me
de ta il in t he hi g hl ig h ts
o
0 . 2% ca u ses t he sa lt so l u ti on to in c re a se t he con t ra s t
a ll o win g in fo r ma t io n in t h e s ha do ws b u t l i t tle in t he
hi g hl ig h t s. T he re i s n ot en o ug h f ree c h lo ri de t o r e ma ke
t he si lv e r c hl o ri de . T his c yc le n ee ds t o c on tin u e t o
ma ke t he me ta ll i c si lve r pa r ti cl es d u r in g t he e xp os u re .
O t he r c h lo r i de sa l t s a re a ls o s ol u b le in wa te r ; t h ese in c lu d e
ca l ci u m c h lo r id e a n d p o ta s si u m c hl o ri d e .
IN ORDER OF WARMTH OF COLOUR
IN ORDER OF LIGHT SEN SITIVITY
1. Ammonia chloride
1. Potassium chloride
2. Sodium chloride
2. Ammonia chloride
3. Potassium chloride
3. Sodium chloride
4. Calcium chloride
4. Calcium chloride
B o t h ca l c i u m c hl o ri de a n d p o ta s si u m c hl o ri d e a re u se d a t t h e
sa me 2 % ra t io t o t he d is t il le d wa te r a s t he a m m on i u m a n d
so di u m c hl o ri de .
A D D I TI V E S T O S A L T F O R M U L AS
S O D I U M C I TR A TE
So di u m ci t ra t e in c r ea ses t he re d u c ti on of t h e si lve r c hl o r id e
a n d sil ve r c i t ra te to me ta ll ic si lv e r on ex p os u re to li gh t .
T he re fo re t he p rin ts wi ll be :
o
Wa r m e r in c ol o u r .
o
L o we r in con t ra s t.
o
Exp os e d f o r le ss ti me .
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 5
SODIUM OR AMMONIUM CHLORIDE + SODIUM CITRATE
D is ti lle d Wa t e r
Sodium chloride or a mmonium c hloride
So di u m ci t ra t e
2 5 0 ml
5 gm
5 gm
M et h o d:
1 . A t r oo m te m p e ra t u r e a d d t h e c h lo ri d e t o t he di s ti lle d wa te r .
2 . T his wil l di sso lv e ea si ly a n d is r ea d y f o r us e wh en
di sso lv ed .
3 . A dd 5 g m s o di u m ci t ra te ; i t is rea d y f o r use wh e n d iss ol ve d .
T he s od i u m c hl o ri de s ol u t ion wi t h s od i u m ci t ra te in c re a ses
t he s pee d b y on e st o p mo r e t ha n a m m on i u m c hl o ri de . T he
a m m on i u m c h lo r i d e wi t h s od i u m ci t ra te in t he s ol u ti o n is
a bo u t 1 0 % wa r me r i n co lo u r t ha n t he so di u m c hl o ri de .
P O T A S S I U M D I C H R O M A TE
P O T A S S I U M D I C H R O M A TE I S P O I S O N O U S
D U S T FR OM T HE D R Y CHE MI CAL IS CA RCI NOGE NI C . S KIN CO NT ACT MA Y CAU S E
DE RMA TI TI S .
W EA R G LO VE S , E YE P ROTE CTI ON A ND A DU ST MA S K .
A dd in g 2 d ro ps o f po ta ssi u m di c h ro m a te 5% so l u ti on t o 3 0 m l
of t he sa l t s ol u t io n yo u wi l l:
o
In c rea s e t h e c on t ra s t o f y o u r i ma ge .
o
In c rea s e t h e ex pos u re ti m e.
Po ta ssi u m d ic h r o ma te be co m es l ig h t- se n si ti ve wh en i t oxi d ise s
wi t h t h e gel a t in . I t re d u ces t he l ig h t s e n si ti vi t y t he re fo re
re q u ir es l on g er e xp os u re ti m es . 17
17
“Potassium dichromate is only light -sensitive when it has something to oxidise for
example gum Arabic or gelatin, it cannot oxidise itself. It reduces sensitivity, hence
t h e l o n g e r e x p o s u r e t i m e s . I t i n c r e as e s t h e c o n t r a s t b y c u t t i n g o f f h i g h - l i g h t s i n t h e
t o n a l s c a l e . The presence of the strong oxidising agent chromium (VI) will ten d to reverse the
photochemical formation of silver metal, re-oxidising it to Ag+, it reduces sensitivity and
increases contrast.” Mike Ware 28/11/07.
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 6
POTASSIUM DICHROMATE 5% SOLUTION
D is ti lle d Wa t e r
Po ta ssi u m d ic h r o ma te
1 0 0 ml
5 gm
M et h o d:
1 . Hea t wa te r to 2 0 °C .
2 . P u t on g lo ves , e ye p r ot ec t ion a n d d us t ma sk .
3 . D iss ol ve 5 g m o f po ta ssi u m di c h r o m a te in t he di s ti lle d
wa t er .
4 . St o re in a s m a ll s t o p pe re d b r o wn bo t t l e .
V a r yi n g t h e a m o un t of p o ta s si u m d i c h ro m a t e a ll o ws s o me
con t r ol . T h e ex t re me u sa ge , i .e . 1 0 % po ta ssi u m d i c h ro ma te
wi l l ca us e los s of i n fo r ma t ion in t he s ha do ws b ef o re t h e r e is
de ta il in t he hi g hl i gh t s. A m m on i u m c hl o ri d e wi t h p o ta s s iu m
di c h r o ma te is 8 % to 1 0 % co ole r in co lo u r t ha n so di u m c h l o ri de
wi t h p o ta ss i u m di c h r o ma te .
SODIUM OR AMMONIUM CHLORIDE + POTASSIUM DICHROMATE
D is ti lle d wa te r
Sodium chloride or a mmonium c hloride
2 5 0 ml
5 gm
M et h o d:
1.
2.
3.
4.
Hea t d is t ill e d wa t e r to 2 0° C .
A dd t he sa l t t o t he di s til le d wa te r . I t will di ss ol ve ea s il y .
Ta ke 3 0 m l o f sa l t s ol u ti on .
A dd 2 d ro ps o f t he 5 % po ta ssi u m d ic h r o ma te s ol u ti on .
BINDERS
Bin de r s
a re
s u bs t a n ces
t ha t
bi n d
t oge t he r
t wo
or
m o re
ma te r ia l s o r c he m i c a ls in a m ix t u re . T h e m os t co m m on l y u sed
in sa l t p rin ti n g a r e ge la tin a r r o wr o o t a n d a l b u men . T h eses
bin de r s ho ld t h e c h lo ri de , di s pe rs in g t he si lve r c h lo ri d e whi le
h ol din g i t to t he p a pe r .
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 7
N B: To a vo i d s po il in g yo u r n e ga ti ve , m a ke s u re t he re is n o
exce ss of t he b in d er le f t on t he ed g es o f t he pa p e r.
t h o ug h
t he
pa pe r
is
dry
t hi s
ex ce ss
or
l u m ps
h ol d s
Even
t he
m ois t u r e a n d a b so r b a g rea t e r % of t he sil ve r n i t ra t e. W hen t he
n ega ti ve
is
pla ce d
on
t he
sen s i ti ze d
pa pe r
s u r fa ce
and
exp ose d , t he h u m i di t y c rea te d b y U V la mp s o r s u n c re a te s
m ois t u r e a n d n o t o n ly s t a in s b u t t he sof t bin de r l u m ps ma y
st ic k t o y o u r n ega t i ve.
G E L A TI N B I N D E R
T he ge la tin e bin de r a ct s a s a si zin g a gen t a n d t he f ol lo wi n g
oc c u rs :
o
T he i m a ge a p pea r s sh a rp e r a s t he g ela tin s to ps t h e
sil ve r c hl o ri de so l u ti on f ro m be in g a bs o r be d in t o t he
pa pe r f ib r es . T he i ma ge si t s on t he p a pe r s u r fa c e.
o
I t m a k es t h e i ma g e c ol o u r a p pea r c oo le r a t a s m a l l
pe r cen ta ge, b ut a s t he p e rc en ta ge in c rea s es t he i ma ge
be co m es wa r me r .
o
T he p rin t wi ll a p pe a r to ha ve a s li g h t sh een , d ep en d in g
on t h e a m o un t o f ge la t in a dd ed t o t h e s ol u ti on .
o
As t he p e rc en ta ge o f gela t in is i n c r ea se d in t he sa lt
sol u t io n t he te m pe r a t u re of t he so l u ti o n n ee ds t o be a t
lea s t 2 0° C be fo re c oa tin g . C ol d ge la tin s ol u ti on s wi l l
beg in to se t a s y o u a re coa t in g , ma kin g a s m oo t h e ven
fin i s h d if fi c ul t to a c hie ve .
SODIUM OR AMMONIUM CHLORIDE SOLUTION + GELATIN
D is ti lle d Wa t e r
Gela t in
D is ti lle d Wa t e r
So di u m c hl o ri de or A m m on i u m C h lo r i de
5 0 ml
2 gm
2 0 0 ml
5 gm
M et h o d:
1 . Mix 2 gm of gelatin with 50 ml of the distilled water at room
temperature, lea ve f o r 1 0 m in u tes .
2 . Hea t t he 2 0 0 ml o f d is ti lle d wa te r t o 4 0 ° C .
3 . A dd t he sa l t.
4 . St i r in t he ge la tin .
5 . T he so l u ti on is rea d y wh en co ole d to a b o u t 2 0 °C .
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 8
A bo u t Ge l ati n : „ Bl o o m fa c to r s ‟ mea s u re ho w r ig id t he g ela t in
sol u t ion is wh en i t se ts . A la b g ra de p u r c ha se d f r o m a
c he m ica l s u p pli e r w ill ha ve a b lo o m n u m be r o f a b o u t 1 2 5, a
su pe r m a r ke t c oo k in g gela t in (a ls o ca lle d ge la tin e ) i s les s t ha n
1 0 0 . T he hi g he r t he bl oo m n u m b er t he f ir m e r t h e ge l fo r a n y
giv en c on cen t ra ti on o f ge la tin .
Foo d g ela ti n a va i la b le f ro m s up e r ma r ke ts co m es in
gra n ula r o r s h ee t f o r m . I t n o r ma l l y h a s t he p res e rva t i ve
2 2 0 s u lp h u r di ox id e ( CO 2 ) . As s oon a s t he s il ve r n i t ra te
sol u t ion is a p p lie d to a sa l t so l u ti on us in g t his t y pe o f
gela t in a s a b in d e r i t s ta r ts to oxi d ise t he s il ve r b ef o re
exp os u re s h o wi n g a ye ll o win g o r c h e mi c a l „ f og gin g ‟ e ffe c t .
T his i mp a i rs t he hi g hl ig h t s a li t tl e. 18
ARROWROOT BINDER
A r ro wr o o t s ta r c h a c ts a s a s iz in g a n d :
o
Cr ea tes a d ee p wa r m ton e
o
En ha n c es d e ta i l in t he s ha d o w r eg ion
ARROWROOT FORMULA19
D is ti lle d wa te r
A r ro wr o o t s ta r c h
D is ti lle d wa te r
A m m on i u m c hl o ri de
So di u m ca r bon a t e
Ci t ri c a c i d
7 5 0 ml
20 gm
2 5 0 ml
14 gm
23 gm
7 gm
M et h o d:
1.
2.
3.
4.
5.
M ix t h e a r r o wr o o t s ta r c h wi t h a bo u t 2 0 ml o f t h e di s ti lle d
wa t er ma k in g a s m o ot h c rea m y s u sp en s ion .
B rin g t o t he b oi l t h e ba la n ce o f d is t ill e d wa te r .
Gra d ua ll y a d d t he s ta r c h wh i le s ti r r in g .
Con tin u e t o b oi l un t il t he li q u i d is t ra n s lu ce n t .
Wi t h t he se con d a m o un t o f di s ti lle d wa te r d iss ol ve in t he
a m m on i u m c hl o ri d e , so di u m ca r bon a te a n d ci t r ic a ci d .
Wh il e a d din g t h e c i t ri c a ci d t his s ol u t io n wi ll e ffe r ve sc e .
18
“Sulphur dioxide is a reductant, apart from the „ fogging ‟ there is no long term
e f f e c t . ” M i k e W a r e 2 0 0 7 . A l a n E l l i o t t s t at e s t h at s o m e S O 2 r e m a i n s b o u n d t o t h e
gelatin.
W a l l , E . J . a n d J o r d a n , F . I . ( 1 9 7 5 ) P h o t o g r a ph i c F a c t s an d F o r m u l as , A m e r i c an
Photographic Book Publishing Co., Inc., New York USA. p 258
19
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
1 9
6.
7.
8.
A dd t he s ol u t ion t o t he a r r o wr o o t a n d b oi l fo r 5 mo r e
m in u tes . T he s m el l of a m m on ia wi l l be q ui te st r on g .
St r a in t h ro u g h c he e se cl o t h wh i le s t ill wa r m , l ea ve t o c oo l.
Re m ove a n y s k in t ha t h a s fo r m ed bef o re a p pl y in g t o t h e
pa pe r .
Coa tin g pa pe r wi t h a r r o wr o o t is m o re c ha l len gin g t ha n o t he r
bin de r s. T he a bo ve fo r m u la is s ui ta bl e fo r c oa tin g wi t h a r od
o r b r us h . If t h e c oa tin g o f t he so l u ti on is t oo t hi c k, t he
sen si t iv i t y of t h e si lve r n i t ra te s o lu t ion de c rea s es . T his
c rea te s a p in k l ig h t b r o wn c ol o u r wi t h pl en ty o f de ta il b u t n o
den s i t y in t he s ha d o w r eg ion s.
N ot e : S od i u m c i t ra te is n e ce ssa r y in t he s ol u ti on a s s ta r c h
a lon e i s n o t a n a c t ive o r ga n i c s u bs ta n ce 20. Ci t ri c a ci d in n ot
n ece ssa r y in t h e si l ve r n i t ra te , i t wi ll i n c rea s e sen si t iv it y b u t
wi l l m a k e t h e pa pe r mo r e d iff i c ul t to to n e. 21
ALBUMEN BINDER
Al b u men is a n „a c t ive ‟ o rga n ic s u bs ta n ce ; i t in c rea s e s
t he re d u ct io n of si lve r c h l or i de a n d s ilv e r a l b u min a t e.
An a l b u m en p rin t is a sa l t p ri n t wi t h t he a l b u men
bin de r . T h is bin de r will a d he r e t h e si l ve r i ma ge on t h e
pa pe r s u rfa ce . Ex p er i men ts on a l b u m en wi t h o u t sa l t were
ca r rie d o u t in 1 8 3 9 b y Ta lb o t a n d in 1 8 4 1 b y R ob e r t H un t . 22
T he i m a ge wa s c r ea t ed f r o m s il ve r n i t ra te fo r m in g s ilv e r
a lb u m in a te s wh i c h re d u ce to m e ta l li c sil ve r on e xp os u r e t o
lig h t . 23
Fre n c h p h o t og ra p he r B la n q ua r t -E v ra r d re fin e d t he p r oc ess b y
a d din g t he c h l or i de a n d a n n o un c e d hi s s u c ces s in 1 8 5 0 . T he
Al b u men p rin t in c o r po ra t in g c hl o ri de be ca me t he pr o m in en t
p rin t in g pr o ces s o f t he mi d 1 9 t h cen t u r y a n d re ma in e d th e
p rin ci pa l p r in tin g m et h o d un t il 1 8 9 5 . 24
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 2 2
20
C r a w f o r d , W . ( 1 9 7 9 ) K e e p e r s o f t h e L i g h t , M o r g a n & M o r g an , I n c . , N e w Y o r k , U S A .
p153
21
22
H u n t , R . ( 1 9 7 3 ) A M a n u a l o f P h o t o g r ap h y , A r n o P r e s s I n c . U S A . p 2 8 6
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r ,
USA.p,28
23
24
Ibid. p28
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 0
ALBUMEN FORMULA
Al b u men (e gg wh i t e )
to 10 eggs)
D is ti lle d wa te r
A m m on i u m c hl o ri de
Gla cia l a ce t i c a c id
250 ml ( approx 8
1 0 ml
4 gm
0.5 ml
M et h o d:
1 . Egg wh i t es m us t be in d iv i d ua l ly a n d ca r ef ul l y se pa ra te d .
T his iso la te s p ro b le ms wi t h o u t s p oi lin g pr ev io u sl y
sepa r a t e d e gg s .
2 . Re m ove a l l co n t a mi n a t ion o f yo l k, s t r i n gy ti ss ue , bl o od o r
sh el l f ro m t he e gg wh i t es .
3 . D iss ol ve a m m on i u m c h lo ri d e in t he di s ti ll ed wa te r a n d a d d
gla cia l a c et i c a c id .
4 . A dd to e gg wh i t es .
5 . Bea t t hi s so l u ti on u n ti l a l l t h e so l u ti on is c on v e r te d t o
fr o t h .
6 . L et t he s ol u t ion s i t fo r 2 4 h o u rs i n t he re f ri ge ra to r .
7 . B rin g t o ro o m t e m p era t u r e .
8 . St r a in t ho u g h m u sl i n o r c hee se cl o t h t o re m ov e fo a m .
9 . Cov e r a n d re f ri ge ra t e f o r 1 wee k to f e r m en t .
Bea t in g t he eg g wh i te b rea ks do wn t h e a lb u m en in t o a
un if o r m c on s is ten c y . T he sa l t a n d t he a ci d a s sis t wi t h
fe r men t in g t he a l b u men s ol u t io n . T h e e a se of coa t in g
in c re a ses a s t h e a l b u men a ges .
T he s il ve r n i t ra t e c oa tin g „ se ts ‟ o r c oa gu la te s t h e f i rs t
coa t in g of a l b u m en . A se con d coa t in g o f a l b u men wi l l in c re a se
t he s u r fa ce gl oss gi vin g a n ex t ra b ri ll ia n ce . U n f o rt u n a tel y t hi s
sec on d c oa tin g w ill s of t en t h e fi r st coa t of a l b u m en .
Ha rd en in g is t h e re fo re n e ces sa r y be f o re a p pl y in g a se c on d
coa t a n d c a n be a c h iev ed b y a n y of t he fol lo win g:
25
o
St o ri n g t he fi r s t c oa t f o r a t lea s t f iv e m on t hs f o r i t t o
slo wl y „ c u re ‟ . 25
o
Pla c in g in a ba t h of iso p r op y l a l co h ol 7 0 % fo r 1 5
sec on ds . T hi s c on s i st en tl y is t he m os t su c ces sf u l
me t h o d wh en a pp l yi n g a s ec on d c oa tin g .
Ibid.p39
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 1
o
St ea min g t he s u rfa c e of t he fi r s t c oa tin g fo r 1
m in u te .
o
Pla c in g a pie ce o f pa pe r ov e r t he s u rf a ce of t he d r y
a lb u m en a n d u sin g a n i r on se t a t te m p e ra t u re
be t we en si l k a n d c ot t on , t h en mo ve t he ir on e ven l y
ove r t he pa pe r . 26
M a n y tex t s a d vi se t ha t 2 % a m mon i u m c hl o ri d e s ho u l d be a d de d
to t he ba t h of is op r o p yl a l co h ol a s t he ba t h lea c h es t he
c hl o ri de f r o m t h e f ir s t c oa tin g. T es ts ha ve p r ov ed t hi s is n ot
n ece ssa r y .
If t h e coa t in g is un sa t is fa c t o r y wh en d r y i t ca n b e p la ce i n a
t ra y of co ol wa te r . The a lb u m en wi ll sof ten a n d even t u a ll y
wa s h off a n d on ce d r y , t he p a p e r ca n b e re coa t ed . I h a ve
fo un d t his us ef u l w hen e xp en si ve ha n d ma de pa p e rs ha v e been
us ed .
ADVANTAGES OF ALBUMEN PRINTS:
o
T he i ma ge si t s on t he s u r fa ce o f t he pa pe r g iv in g t he
a p pea ra n ce o f a g re a te r den s i t y ra n ge t h r o ug h t he
re f ra c t io n of t he l ig h t .
o
An a l b u men p rin t h a s a s li g h t s heen to glo ss y f in is h ed
su r fa ce gi vi n g b r il li a n ce , a b sen t in sa l t ed pa p e r p r in ts .
U sin g a m m on i u m c h lo ri de in t h e a l b u me n s ol u t ion res u l ts i n
t he co lo u r bein g 8 % to 1 0 % c oo le r t ha n us in g s o di u m c hl o ri de .
B y a d din g 2 d ro ps of p o ta s si u m di c h r o ma te 5% s ol u ti on i n 3 0
m l of t he a l b u m en s ol u ti on wi ll :
o
In c rea s e t h e c on t ra s t o f y o u r p r in t.
o
In c rea s e ex po s u re t i me .
S I L V E R N I TR A T E S E N S I TI S E R
S I L V E R N I TR A TE I S P O I S O N O U S
I T IS A N O X ID IZ I NG A GE N T , CAN CA USE SE R IO U S PE R MA NE N T
D A M A GE TO E YE S . WEAR GLOVES AND EYE PROTECTION.
J a m e s , C . ( 2 0 0 2 ) T h e B o o k o f A lt e r n at i v e P h o t o g r a p h i c P r o c e s s e s , D e l m ar , N e w
York.p267
26
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 2
T he si lv e r n i t ra te sen si t is in g s ol u t io n m us t be ma de u sin g
di s til le d o r de -i o n iz ed wa te r . Si lv e r n i t ra te rea c t s wi t h
c hl o ri de a n d a n y ha r d wa te r ion s s u c h a s ca r b on a tes t ha t ma y
exis t in ta p wa te r su p pl ies . T h e re s ul t o f c on ta min a t ion is a
cl o u dy wh i t e p re ci pi ta t e of s i lve r c h lo r id e a n d s i lve r
ca r bon a t e. T hi s de p ri ves t h e s il ve r n it ra t e o f i t s s t ren gt h ,
ma k in g sen si t isin g t he pa pe r le ss ef fe c t ive . 27
SILVER NITRATE SENSITISING FORMULA
D is ti lle d o r de - min e ra li ze d wa te r
Sil ve r n i t ra t e
5 0 ml
6 gm
M e th o d:
1.
2.
3.
P u t on g lo ves a n d e ye p ro te c ti on .
A dd t he s il ve r n i t ra te to t he di s til le d wa te r .
St o re in a b ro wn gla ss b o t tle .
Sil ve r n i t r a t e is n ot sen s i ti ve to l ig h t un l ess t he re is a n
oxi da n t p resen t . M ixin g s ma l l a mo un ts of si lv e r n i t ra te
sol u t ion re d u ces t h e ri s k of con ta m in a t ion t h ro u g h u sa g e .
If us in g t he gla ss r od me t h o d , t he a b o ve so l u ti on wi l l c oa t 2 0
to 2 5 s hee t s of pa pe r f o r 8x 1 0 in c h p rin t s . M o r e so l u ti on is
us ed f o r t h e b r us h me t h o d , de pen din g on t he b r us h ty p e a n d
si ze.
Inc re a se Si l ve r Ni t r ate Pe rc e n tag e : S m a ll in c rea se s in t he
pe r cen ta ge o f sil ve r n i t ra te in t h e so l u t ion ca n be ben efi c ia l in
p rin t in g l o w c on t ra st n e ga ti ves . A s t h e pe rc en ta g e in c r ea s es
b ron z in g a f fe c ts t h e s ha d o w r eg ion s a n d y el lo wi n g in t he
hi g hl ig h t s wi l l b egi n to s p oi l t he p rin t ‟ s t on a l ra n g e .
27
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r ,
USA.
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 3
THE EFFECT OF INCREASING THE SILVER NITRATE:
o
1 5 % in c rea s es t he con t ra s t . T he co lo u r i s c oo le r a n d
sh o ws so m e l oss of de ta il in t h e s ha do ws . T he hi g hl ig h t
de ta il is m o re a pp a r en t . T he p rin t is s ti ll a c ce p ta b le.
o
2 0 % c re a t es f u r t h e r i n c rea se in t he con t ra st a n d a
fu r t h e r lo ss o f de t a il in t he s ha d o ws . T he re is so m e
b ron z in g a n d m o re de ta il in t he hi g hl ig h ts .
o
3 0 % in c rea se s t h e c on t ra s t , a l lo win g l i t tl e de ta i l in t he
sha d o ws . B r on zin g be co m es o bv io u s a n d t h e re is le ss
de ta il in t h e hi g hl ig h ts . T he h ig h li g h ts ma y be c o me
ye ll o w.
De c r e a se Si l ve r Ni t ra te Pe rc en t ag e: A sm a ll r ed u c t ion in t he
pe r cen ta ge of si lv e r n i t ra te in t h e s o lu t ion ma y s ho w s o me
ben e fi t s in p rin t in g h ig h con t ra s t n e ga t ive s . As t h e p e rc en t a ge
be co m es s ma ll er t h i s ma y res u l t in wea k in e ff ec t ive p rin t s .
THE EFFECT OF DECREASING SILVER NITRATE:
o
1 0 % de c re a ses t he con t ra s t a n d t he p rin t a pp ea rs
wa r m e r in c ol o u r . T he p rin t ma y be s t ill sa t isfa c t o ry .
o
5 % t he p r in t beg in s to lo se h ig h li g h t de ta il b u t ga in s
sha d o w d e ta i l a n d i n c rea s es t he wa r m t h o f t h e c ol o u r.
o
1 % s h o ws li t t le de ta i l in t he h ig h li g h ts a n d t he m i d
to n es de c rea se in c on t ra s t . T h e s ha do w de ta il is wea k .
Sp o ts de sc r i be d a s „ mea sle s ‟ m a y a p pea r a f te r s o me
ti m e.
T he li g h t sen s i ti ve su bs ta n ce in sa l t a n d a l b u men p a p er i s
sil ve r c h lo r i de . Si l ve r c h lo r id e is in s ol u bl e in wa t e r . S o di u m
c hl o ri de so l u ti on is c oa te d on t he pa pe r fo ll o we d b y t h e s i lve r
n it r a t e so l u ti on t h us c rea ti n g si lv e r ch lo r i de a n d so d iu m
n it r a t e. So di u m n i t ra te i s so l u ble a n d is wa s he d a wa y d u ri n g
t he p r oc ess in g . I f t he c h lo r id e a n d t he sil ve r n i t ra te a r e e q ua l
or
si m ila r
c h e m ica l
eq u iv a len t ,
lig h t
sen si ti vi t y
is
d ra ma t ica ll y re d u c ed . Ex ce ss s il ve r n it r a t e a l lo ws m o re
me ta ll i c sil ve r to b e fo r me d in t he p r i n t , t h u s in c r ea s in g t he
den s i t y.
T he c i t ri c a ci d a d de d to t he s il ve r n it r a t e so l u ti on c r ea t es
sil ve r c i t ra te , in c re a sin g s pe ed a n d wa r m in g t he c ol o u r ton es. 28
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr ac t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 4
28
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 4
SILVER NITRATE FORMULA WITH CITRIC ACID
D is ti lle d o r de - min e ra li ze d wa te r
Sil ve r n i t ra t e
Ci t ri c A c id
5 0 ml
6 gm
0.75 gm
M et h o d:
1 . P u t on g lo ves a n d e ye p ro te c ti on .
2 . A dd t he s il ve r n i t ra te to t he di s til le d wa te r .
3 . A dd t he ci t r ic a ci d .
4 . St o re in a b ro wn gla ss b o t tle .
M ixin g s m a l l a m o u n ts o f s il ve r n i t ra t e s ol u ti on r ed u ce s t he
ri s k of con ta m in a t i on t h r o ug h usa ge .
A high percentage of citric acid can cause bronzing as it increases
the speed the silver citrate and silver chloride conversion to
metallic silver.
T he Sa l t p ri n t M a n u a l | T he Sa l t a n d Sil ve r Fo r m u la s
2 5
C HAPTER
5
5. T H E P AP E R
S a l t pr i n t i ng br i ng s yo u i n to uc h w i t h t he a n c i en t c r a f t o f
p a p er m a k i ng . A b as i c un d ers t a n d i n g o f t he s tr u c t u re a n d
te x t u res o f p a p ers w il l p ro vi d e an o t h e r to o l to co n t ro ll i ng t he
co lo ur a n d t he f i n a l lo o k o f yo u r pr i n t . T he re a re m a n y p a p ers
t h a t w i l l no t w o rk w it h t h is pro c es s . T he re fo re y o u a re l i m i te d
to us i ng q u a li t y 1 0 0 % r a g co t to n w a te r co lo ur p a pe rs . T h is
c h a p te r e x p l ai ns w h y a n d o f fe rs s o m e s ugg es tio n o n v a r io us
p a p ers to tes t . T he Bo o k o f F i n e P a pe rs b y S i lv i e T ur ne r is a
b ri l l i a n t bo o k o n t h e h is to ry o f p a p er as w el l as a w o r l d w ide
gu i d e o n f i ne p a pe rs a n d p a p er m i l ls .
1 0 0 % c o tt on p a p e r is t he p u re s t f o r m o f ce ll u lo se of f er in g
hi g h s t ren g t h a n d t he l on g es t li fe o f a ll pa pe r s. 29 Co t ton is a
sta b le ba s e fo r t h e si lv e r n i tr a te so lu t ion t he re fo r e m o re
p re di c ta bl e in i ts re sp on s e t h ro u g h t he p r oc ess . Si zin g is
a d de d to p r ev e n t s ol u ti on s f r o m s oa ki n g to o dee p ly in t o t he
pa pe r t h us ma kin g t he c oa ti n g mo r e un if o r m . T he f ib r e s in
pa pe r a r e ma de u p of s ho r t e r co t t on lin te rs o r c o t ton „ r a gs ‟.
Ra gs f i b res a re lon ge r a n d s t ron ge r b u t les s co m m on l y u s ed . 30
U n de r st a n d in g t h e c ha ra c te ri s ti cs of pa pe rs , t he i r l ife a n d
be ha vi o u r is o f g rea t va l ue wh en c ho os i n g pa pe rs . 31
P AP E R M A N U F A C TU R I N G
Fa b r ia n o in t r o d uc ed wa te r ma r k s in 1 2 7 2 . A c tin g a s re c ogn i ti on
of t he ma ke r , t h ey p r o mo t e a n a ss u m p ti on o f q ua li t y.
Wa t e r ma r ks a re n o r ma ll y cl ose t o t h e edg e o f t h e pa pe r a n d
“ rea d r ig h t ” f r o m t h e to p s i de.
Pa pe r m a kin g ca n b e di vi de d in to t he t h re e f ol lo win g gr o u ps ;
ha n d ma de , mo u l d m a de a n d ma c h in e ma de .
29
T u r n e r , S . ( 1 9 9 8 ) T h e B o o k o f F i n e P a pe r s , T h am e s a n d H u d s o n I n c , N e w Y o r k . p 1 6 2
30
Ibid.p21
31
Ibid.p19
T he Sa l t p ri n t M a n u a l |
2 6
TYPE
A D V A N TA G E S
D I S A D V A N T AG E S
HAND-MADE
Handcrafted cotton or
linen individual sheets,
little grain so therefore
stronger.
Expensive, unknown purity
and irregular sizes.
CYLINDER
MOULD MADE
Quality is consistent, less
expensive than handmade,
wide variety and easily
available. Most watercolour
rag papers are made on a
mould in the form of a
cylinder
MACHINE-MADE
Cheap and readily
available.
O wi n g t o t h e w i d e v a r i e t y
it requires research to
understand the various
types suitable for salt
printing. Grain is laid in
one direction therefore not
as strong as handmade
papers
Av o i d f o r i m a g e m a k i n g . I t
is a major problem for
longevity as it is usually
f r o m wo o d p u l p , l i g n i n
bleaches and other
additives that contribute
t o a c h e m i c a l b r e a k d o wn
in the paper.
A D D I TI V E S T O P A P E R
1 . S i zin g . Si zin g i s a d de d to in c rea s e su r fa ce s t r en g t h a n d
re sis t s t he pen e t ra ti on o f so l u ti on s i n t o t he fi b res of t he
pa pe r . Ge la tin a n d s ta r c h a re t he m os t c o m mon t y pe s of si z in g
su i ta ble fo r sa l t p rin t in g . Al k yl - ke t en e - di m e r ( A K D ) i s a
syn t he t i c a r c h iva l i n te rn a l si zi n g a gen t whi c h a l lo ws t h e p a pe r
to re m a in n e u t ra l p H. A q ua p el i s on e of t he t ra de n a me s fo r
t hi s hy d r op h o bi c o r wa te r re pe llen t si zin g . Ge la tin e si zin g
c rea te s a c oo le r to n e in t he p a p e r. 32 A wa r m e r c ol o u re d sa l t
p rin t i s fo r m e d u sin g s ta r c h s iz in g .
Wa y s of s i zin g:
o S u rfa ce si z in g a ls o ca l le d t u b si z in g . T he d ry f in i s he d s h e et
is i m m e rs ed in a b a t h of h o t gela t in fo r m in g a s kin o ve r t he
pa pe r s u r fa ce a n d ha r den e d . T his is a pe r fe c t s u r fa ce f o r
sa l t p r in tin g.
32
Ibid. p133
T he Sa l t p ri n t M a n u a l | T he Pa p er
2 7
o
In te rn a l si z in g is k n o wn a s b ea te r o r ma c hi n e . T he si z in g is
a d de d t o t he p r o ces s be fo re t he f o r ma t i on of t he s h ee ts . 33
2 . Fil le rs a n d loa d in gs . M in e ra l pi g me n ts b in d t he f i b r es
to ge t he r , f il lin g be t we en t h e ga ps c r ea t in g den s e r s hee ts . 34
T hese in cl u de c a l c iu m ca r bon a te (a c i d b uf fe r ), C hi n a c la y
( ka o lin ) , t i ta n i u m d iox id e a n d o p ti ca l b ri g h ten e r s. Av oi d t h ese
a s t h e y rea c t wi t h t he si lve r n i t ra te be fo re ex pos u r e, c re a tin g
c he m ica l f ogg in g .
3 . Wa t e rlea f . A te r m fo r n o s i zin g a n d t h e ref o re ve r y
a bs o r ben t. I t is p r ob le ma t ic fo r sa l t pr in tin g c re a t in g fla t
p rin t s a n d u n ev en co lo u r d ue t o t he hi g h a n d in c on si s ten t
a bs o r pt io n ra t es o f t he s ol u t ion s.
SURFACE FINISHING
o
Ro u g h. In h a n d ma de p a p e rs i t is a i r dr ie d c rea t in g a
r o ug h te x t u re d s u r fa c e . In mo u l d ma de , a r o ug h fel t
ma ke s t h e r o ug h s u rf a c e . 35
o
NO T . C ol d p re sse d wh i c h m ea n s i t is n ot h o t p ress e d a n d
is ha l f- wa y be t we en ro u g h a n d ho t p res s wi t h a tex t u re d
fin i s h
o
Ho t P r ess . A s m oo t h fi n is h us in g ho t r oll e rs o r p r ess ed
t h ro u g h c ol d po lis h ed me ta l r ol le rs .
WEIGHT AND DENSITY
T hi c kn es s o r we ig h t is r efe r r ed to a s gra m s pe r s q ua re me t r e
(gs m ) . 2 8 0 gs m to 3 0 0 gs m is i dea l fo r sa l t p rin t in g b u t wi t h
ca re l ig h te r we ig h t s c a n be us ed .
Den si t y re la tes t o h o w we ll t he pa pe r i s b on d ed . Den se pa pe r
wi l l ex pa n d a n d c on t ra c t a s a wh o le a n d i ts ten de n c y t o c u r l is
n o t a s g rea t . Pa pe r wil l c u rl mo r e wh en d en se r fi b re s a r e on
t he to p s i de o f a she e t . T he s pe ed o f ex pa n s ion a n d
con t ra c t ion a re t he r efo re a t di ffe r en t ra te s. 36
33
Ibid. p24
34
Ibid. p25
35
Ibid. p28
36
Ibid. p35
T he Sa l t p ri n t M a n u a l | T he Pa p er
2 8
CARE OF PAPER
o
Ha n dle a s li t t le a s p oss ib le a n d b y t he e dge s , i dea ll y use
wh i t e c o t ton gl ove s. A v oi d c re a sin g t h e pa pe r .
o
St o re f la t . Ro lle d pa pe r o ve r t i me c r ea t es a „ me m o r y‟
wh i c h ma k es t he pa pe r dif fi c u l t t o fla t t en o u t.
o
Re m ove ma r ks ca r ef ul l y wi t h a so f t b r u s h o r e ra s e r.
D is t u r b in g t h e s u r fa c e of t h e pa p e r ma ke s i t m o re
a bs o r ben t a n d ma y re m ov e t he si z in g . St a in s m a y a p pea r
in t he se a rea s .
PAPERS FOR SALT PRINTING:
Pa pe rs s u it a b le f o r sa lt p rin t in g ha ve a rig h t a n d wr on g si de
d ue to t he s u r fa ce s iz in g a n d t h e fin is h in g .
o
T he pa pe r c h oi ce wi l l a ffe c t t h e co l o u r, c on t ra s t a n d
to n a l se pa ra t ion of yo u r i ma ge .
o
Te m pe ra t u re a n d h u m id i t y wi ll a ffe c t t h e a bso r p t ion
ra te of t he so l u ti on s.
o
To u c hin g t he pa pe r s u rfa ce in t he i ma ge a re a wi l l l ea v e
oil s a n d sa l t f r o m yo u r s k in a n d ma y ca use s ta in i n g in
t he f in a l p rin t .
o
S mo o t h, ha r de r f in is he d s u r fa ce s i ze d pa pe r s gi ve a
sha r pe r , m or e b r il li a n t i m a ge .
o
So l ut io n s sin k in t o po ro u s pa pe r . T h e im a ge a p pea rs
sof t er , c rea tin g a d ul l ma t t a p pe a r a n c e .
Tex t u re d p a p e rs a re m or e d iff i c ul t to coa t . T h is ca n be
ove r c o me b y us in g a b r us h to a p pl y t h e so l u ti on . T he tex t u re
re f ra c t s t h e li g h t , fl a t ten in g t he i m a ge a p pea ra n ce .
L is te d b el o w a re pa pe rs I ha v e u se d , in o r de r o f p r efe r en c e .
1 . BE RGG ER CO T 3 2 0 M O U L D M A DE 3 2 0 g sm HP ( F ren c h) . 1 0 0 %
co t t on un - b uf fe re d a n d s u rfa ce s iz e d wi t h gela t in . M a de on
a c yl in de r m o ul d , t hi s pa pe r wa s c re a te d sp ec if ic a ll y f o r
pla t in u m p rin t in g . I t is e x ten s ive l y use d f o r o t h e r
a lt e rn a ti ve p ho t og r a p hi c p ro ce sses a s it is a ci d- f ree , ha s n o
op t ic a l b rig h t en e rs a n d is Ne u t ra l p H .
A dva n ta ges : I t ho l ds t he t on es be t te r t ha n a l l o t he r pa pe rs
te st e d t o da t e. T h e sa l t p r in t is a co ol dee p b ro wn co lo u r a n d
is c on s is ten t in it s pe rf o r ma n ce a n d q u a li t y.
T he Sa l t p ri n t M a n u a l | T he Pa p er
2 9
D isa dva n ta ges : T h is pa p e r is a l it t le m o re ex pe n si ve .
2 . TAL BO T HA N DM A DE 2 4 0 gs m 1 0 0% (F r e n c h ), 1 0 0 % lon g f i b re
co t t on , ma t t fin is h a n d s u rf a c e s iz e d wi t h ge la tin . S hee ts
a re p re sse d sev e ra l ti me s in b o t h wet a n d d r y s ta t e t o
m in i m ise po r os i ty .
A dva n ta ges . I t h el d t he ton es in bo t h hi g h li g ht a n d s ha d o ws
sh o wi n g 1 8 s te ps . Th e sa l t p rin t i s wa r m dee p re d b r o wn
co lo u r a n d is con si s ten t in pe r fo r ma n ce a n d q ua li t y .
D isa dva n ta ges . T h e re a re s o me in t r in si c in con sis t en c ies i n t he
pa pe r ; b u t t hi s is e xpe c te d wi t h ha n d ma de pa pe rs . T h is pa pe r
is a li t t le m o re e xp e n siv e .
3 . ARC HE S PL AT I N E M O U L D M A DE ( F ren c h ) 3 1 0 g s m H P 1 0 0 %
co t t on .
It is un - b uf fe re d a n d s u rfa c e si ze d wi t h s ta r c h .
Ac i d- f ree wi t h n o op t ic a l b ri g h ten e r s a n d is N e u t ra l p H.
M a de a t t he A r c hes m il l in F ra n ce on a c yl in d e r mo u ld , t hi s
pa pe r wa s c rea t ed spe c ifi ca ll y f o r pla tin u m p r in t in g. I t i s
a lso ex te n si ve ly u sed f o r o t he r a l te rn a t ive p ho t og ra p h ic
p ro ce sse s.
A dva n ta ge s : H ol ds t he ton es ex t re me l y wel l a n d i s c on si s t en t
in i ts p e rf o r ma n ce q ua l i t y , a n d is u s ua ll y a va ila bl e .
D isa dva n ta ges :
pa pe rs .
This
pa pe r
is
m o re
exp en si ve
t ha n
o t he r
4 . FA BR I A NO A RT I ST IC O M O U L D M A DE ( I ta l ia n ) 3 0 0gs m H P 1 0 0 %
co t t on . I t is un - b uf fe re d a n d s u rf a c ed si ze d , a l so a va ila b l e
in a r o ug h s u r fa c e whe r e be s t r es ul t a re a c hi ev ed b y
b r us h in g t he c oa t in g on .
A dva n ta ges : T he s u rf a c e s i zin g h ol d s t he t on e s we ll . I t is
in ex pen s iv e a n d rea di l y a va i la bl e .
D isa dva n ta ges : T he pa pe r is q u i te wa r m in co lo u r s o t he
hi g hl ig h t s a re n o t a s c lea n a s t h e p rev i o us pa pe rs . O c ca s io n a l
p ro b le ms f o un d wi t h q ua l i ty in c on s is te n ci es .
5 . BU XTO N HA N DM A DE PL A T I NO T YP E 2 4 0 gs m 1 0 0% c ot t on H P
un -b u f f er e d in te rn a ll y si ze d wi t h Al k y l - ke ten e - di m e r ( A K D )
a syn t he t i c a rc h iva l in t e rn a l s i zin g a ge n t , t his h y d ro p h o bi c
o r wa te r re pel len t s iz in g . P r o d uc ed in R us c o m be M i ll F ra n c e ,
it wa s de vel o pe d i n co lla b o ra ti on wi t h D r M i ke Wa re fo r
pla t in u m p r in tin g .
T he Sa l t p ri n t M a n u a l | T he Pa p er
3 0
A dva n ta ges :
C ol o u r
M id
ton e s
se pa r a te d
we l l.
T h is
p a p er
w o rke d ex t re m e ly w el l fo r al b u m e n pr i n t i ng g i vi n g t h e f i nes t
res u l t o f a l l p a p e rs a n d s ur f a c es t es te d w it h t h is fo r m u l a .
D isa dva n ta ges : W he n a p p ly in g t he si l ve r n i t ra te so l u ti o n t o
t he sa l t t he A K D c rea t ed a c h e mi ca l fog wh i c h re d u ce d t he
hi g hl ig h t s a n d f la t ten ed t he s ha d o w reg ion s a li t t le. T his
pa pe r n ee d to b e we ll se c u re d wh i le c oa tin g , d ue t o t he li g h te r
we ig h t i t wi l l c u r l w hen m oi st u r e is a p p lie d .
OTHER PAPERS TRIED :
o
SAU N D ER S WA TE RF O R D (En gl is h ) 3 0 0 gs m HP 1 0 0 %
co t t on un - b uf fe re d , in te r n a ll y a n d s u rf a c e si ze d wi t h
gela t in e . A ve ra g e p ri ce ra n ge ho ld s t on es we ll , ha s a
ve r y wa r m to n a l r a n ge .
L os es t he hi g hl ig h t s t o t he
wa r m t on es of t he pa pe r. Al so a va i la bl e in 1 5 0g s m a
lig h t l y tex t u re d s u r fa c e . wh i c h s ho w a m in o r fla t ten in g
of t he i ma ge .
o
R IS I NG S TO NE HE NG E M A CH I N E M A DE ( En gl is h ) 2 4 5 gs m
NO T 1 0 0% c o t ton , b uf fe re d wi t h ca lc i u m ca r bon a t e.
In ex p en si ve
pa pe r .
The
c a l ci u m
ca r bon a t e
is
p ro b le ma ti c wi t h t he sen s i ti vi t y of si lve r n i t ra te . T h is
pa pe r is a bs o r ben t , c rea ti n g a d u ll p rin t .
o
AR CHE S AQ U A REL L E M O U L D M A D E (F r e n c h ) 3 0 0 gs m H P
1 0 0 % c ot t on un - b uf fe re d, in t e rn a l l y a n d s u rfa ce s iz ed
wi t h ge la tin e . G iv es a r ea s on a ble t on a l ra n ge wi t h
pl ea sa n t wa r m t on es. M o r e e x pe n si v e t ha n F a b r ia n o
A r tis t i co .
o
FA BR I A NO T IE PE L O M O U L D M A DE Wa t e r co lo u r ( I ta l ia n )
2 9 0 g s m 1 0 0 % co t to n in te r n a l ly s i ze d . A wel l p r ic e d,
ve r y so f t s u rfa ce d p a pe r wi t h a hi g h a bs o rp t ion ra te ,
un s u i ta ble fo r pla in sa l te d p ri n ts b u t i m p ro ve s wi t h a
gela t in b in de r a n d e xt ra s iz in g .
o
L A NAQ U AL L E M O U L D M A DE , 3 0 0gs m HP , 1 0 0 %
un -b u ff er e d, i n t e rn a l & ex t e rn a l l y si z ed . We ll
b u t res u l ts ha ve be en d isa p po in tin g re su l tin g in
p rin t s d ue t o t he u n even a b so r p ti on , e ven wi t h
in t he s a l t s ol u ti on .
o
CR A NE‟ S D I PL O M A PA RC HM E N T (U S A) ( re pla ce m en t f or
Cra n es P la tin o t yp e) M A CH I NE M A D E 1 7 7g s m H P 1 0 0 %
co t t on R osin & A l u m s iz ed .
c o t ton ,
p ri ce d,
b lo t c h y
bin de r s
T he Sa l t p ri n t M a n u a l | T he Pa p er
3 1
o
CR A NE K I D F I NI S H (U SA ) gs m 1 4 0 1 0 0 % co t t on un p res se d L ig h t we ig h t n ee ds ca re f ul ha n d lin g c oa ti n g a n d
in p r oc ess in g ba t hs .
ADDING SIZING TO PAPER
M a n y pa pe rs a re s i ze d d u r in g ma n u fa c t u rin g a n d bin de r s a ct
a s si zin g , h o we ve r t he re a r e s ti ll t he f oll o wi n g a dv a n ta ge s in
p re - si zi n g o r res i zi n g t he pa pe r bef o re c oa ti n g .
1.
2.
3.
4.
5.
U sin g po r o us pa pe r s t ha t a re n o t p re - si ze d.
A dd in g a n ex t ra f in i sh t o t he s u r fa ce .
U sin g pa pe rs t ha t a r e hi g hl y tex t u r ed .
T he d if fe ren t s iz in g t yp es a l lo w c on t r ol o f t h e c ol o u r.
U sin g di ffe r en t t y pe s of s u r fa c es .
T he si z in g c a n be :
o
o
o
Ge la t in .
Gela t in ha r de n e d wi t h g ly oxa l .
A r ro wr o o t .
GELATIN SIZING
D is ti lle d Wa t e r
Gela t in
D is ti lle d Wa t e r
1 0 0 ml
30 gm
9 0 0 ml
M et h o d:
1.
2.
3.
4.
5.
A dd 1 0 0 ml of t he wa te r to t he gela t in .
Al lo w t o b lo o m (s we ll ) fo r 2 0 min u t es a t ro o m te m pe ra t u re .
A dd t he 9 0 0 m l of t h e wa te r .
Hea t to 6 0° C.
Po u r s ol u ti on in to a wa r m t ra y . Si t t h is t ra y in s id e a la rg e r
t ra y fi ll ed wi t h h o t wa te r to ma in ta in a te m pe ra t u re of a t
lea s t 2 0° C.
6 . A dd s h ee ts o f pa pe r on e a t a ti m e.
7 . S h uff le t h e s he e ts fo r a t lea s t 3 m i n u te s a n d u p to 5
m in u tes .
8 . Re m ove s hee ts on e a t a ti m e, a n d pl a ce on a fi r m fla t
su r fa ce .
9 . U sin g a g la ss ro d si m ila r in s i ze t o t he pa pe r , g en tl y
sq ue ez e t h e ex ces s sol u t ion do wn a n d off t he e d ge o f t h e
pa pe r .
1 0 . Ha n g to d r y.
If t he so l u ti on c oo ls b el o w 2 0° C, i t wi l l n o t coa t e ven l y . A
sec on d c oa t of gela t in wi l l a ss is t wi t h r o ug h tex t u re d s u r fa ces .
T he Sa l t p ri n t M a n u a l | T he Pa p er
3 2
H A R D E N I N G TH E G E L A TI N S I Z I N G :
Ch e mi ca ls us ed f o r ha r den in g gel a tin a re gen e ra ll y d a n ge r o us .
O n ly use t h e m i f yo u fin d t he u n ha rd en ed gela t in s i zin g is n o t
a de q ua te . A vo i d fo r ma ld e h yd e!
If y o u d o no t ha ve ac c e s s to a f u m e c up b oa rd , wea r r u b be r
g l o ve s, g a s m a sk a nd e y e pr o tec ti on .
T he Sa l t p ri n t M a n u a l | T he Pa p er
3 3
GLYOXAL HARDENING FORMULA
Wa t e r
Gl yox a l 4 0%
1 0 0 0 ml
5 0 ml
M et h o d:
1.
2.
3.
4.
5.
6.
P u t on ma s k , gl o ves a n d ey e p r o te c ti on .
A dd t he g l yox a l to t he wa t er .
A dd t he s o di u m ca r bon a t e.
Pla ce t he s h ee ts in ba t h .
Ca r e f u ll y s h uf fl e t h e s h ee ts f o r 1 0 m in u te s .
Re m ove a n d p la ce in a fr es h wa te r ba t h to re m ov e ex ces s
ha r den e r . 37
7 . W a s h fo r 2 0 m in u te s c ha n g in g wa t e r a b o u t e ve r y 5 min u te s .
8 . Ha n g to d r y in a wel l ven ti la te d ro o m .
T he a d di ti on of so di u m ca r b on a te c re a te s a n a l ka lin e b a t h t o
a ssi st t he b in din g b et we en si zin g a n d h a r d e n e r a s t he h ig h p H
ma x i m is es t he h a r den in g 38. T his wi ll c rea t e se ve r e c he m i cal
fog gin g t h e ref o re i s o m i t te d f ro m t h e f o r m ula .
37
W a r e , M . ( 2 0 0 6 ) T h e C h r y s o t y p e M a n u a l, T h e C r o m w e l l P r e s s L t d , U K . p 4 7
W a l l s , H . J . a n d A t t r i d g e , G . G . ( 1 9 7 7 ) B as i c P h o t o S c i e n c e , h o w ph o t o g r ap h y w o r k s ,
Focal Press, London. p212.
38
T he Sa l t p ri n t M a n u a l | T he Pa p er
3 4
C HAPTER
6
6. C O AT I NG
TH E
P AP E R
O ne o f t he o r ig i n a l m et ho ds us e d to co a t p a p er w as to fl o a t t h e
s he e t o n t h e s u r f ac e o f a s o l u t io n i n a “ b a t h ” o r tr a y . A mo re
co n tro l l e d m et ho d i s to us e a g l as s ro d a n d a s yr i ng e to a p p l y
t he s o l u t io ns . T h e c o a t i ng is mo re ev e n a n d t h e r a t io be tw ee n
t he s a l t a n d t h e s i l v er ni t r a te s o l u t io n i s mo r e co ns is t en t
Coa tin g t h e pa pe r is b r o ken in t o t he foll o wi n g t h ree b a si c
me t h o ds .
1 . Fl o ati ng or s u bm e rg i ng i n a s ol u ti o n Ba t h . T h e
pa pe r ca n b e c o m pl ete l y s u b me r ge d o r t he e dg es o f
t he pa pe r ca n be t u rn e d up t o r es em b le a b oa t
flo a t in g on t h e s u rf a ce o f t h e so l u ti on .
2 . Bru s hi ng On . U s in g b r u s hes wi t h m e ta l pa r ts wi l l
rea c t wi t h t he s il ve r n i t ra te s ol u t ion . S pon ge b r us he s
a n d B uc k le b r us hes wo r k wel l . A B uc k le b r us h i s ma de
b y t wis t in g co t t on w oo l in to a tes t t u be .
3 . Dr ag g i n g o r pu s hi ng t he s ol u ti o n . G la ss ro ds , a ls o
kn o w a s p ud d le p u s he r s o r c h e mi ca l p u sh e rs , p us h t he
sol u t ion ev en l y a c r oss t h e pa pe r , b y mea s u rin g t he
sol u t ion o u t wi t h a sy r in ge t h is coa tin g s ys t e m i s
ec on o m i c, fa s t a n d p re ci se.
ADVANTAGES
DISADVANTAGES
Floa t in g
Often stated as an even way
of coating the paper.
B r us h in g
Relatively fast, easy method.
Sponge brushes are cheap
and easily obtained.
Brushes for salt can be
reused.
P us h in g
Economic, precise, fast and
easy method. Glass rods are
reusable, easily washed
leaving no chemical trace.
Inexpensive.
More solution is used therefore,
longer drying time. The quantity of
solution absorbed into the paper is
inexact.
Even coatings can be difficult.
Brushes for the silver nitrate
solution become contaminated
when coating the salted paper and
need careful washing, or to be
replaced.
The rod needs to match the
negative size; a flat firm surface is
required for coating. The glass rods
are breakable.
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
3 5
P R E P A R I N G TH E P A P E R
Cu t o r tea r t he pa p er a bo u t 5 0 m m ( 2 i n c hes ) wi de r t ha n
yo u r n e ga ti ve o r i ma ge si ze . T he ex t ra wi d t h m a kes
ha n dl in g t h e pa pe r ea sie r t o a v oi d to u c hin g t he i m a ge
a rea . M a ke s u re t he wa te r m a rk i s n o t i n t he i m a ge a r ea .
Al lo w r o o m fo r t he st ep we dg e. M a r k o u t t h e i m a ge si ze
a n d n o te in pen c il on t h e ed ge o r on t he re ve rs e of t he
pa pe r ( o u ts id e t h e i ma ge a rea ) t h e fo ll o wi n g :
1 . T he so l u ti on y o u a r e us in g .
2 . T he a mo un t of s ol u t ion ( if us in g a s y ri n ge) .
T he ro d s ho u ld si t a t lea s t 2 0 m m in f r o m t he o u t e r e dge s of
t he pa p e r . I f t h e s ol u ti on m ig ra t e s ov e r t h e e dg es a n d a bso r bs
in t o t he re ve rse si de o f t he p a p e r i t wo u l d c rea te a p ro bl e m
fo r t h e n ex t co a t. Silv e r n i t ra te so l u ti on a b so r bs un e ven l y
t h ro u g h t he pa pe r , da r ke r s ta in s i den t if yin g wh e re sa l t
sol u t ion h a s a bs o rb ed in to t he pa pe r s re ve rs e . A pa pe r to we l
un de r t h e pa p e r a ll o ws s up p len e ss on t he pa pe r s u rf a c e
ma k in g i t ea sie r to coa t e ven ly .
Kee p in g t he pa pe r a n d t he so l u ti on a t r oo m t e m pe ra t u re
m in i m ise s t he c u r li n g o r b u c k lin g o f t he pa p er a s t h e s ol u ti on
is a pp li ed . St o p t he pa pe r m ov in g d u rin g a p p li ca ti on by ta p in g
do wn t h e c o rn e rs to t he gla ss s u r fa c e o r pin to h ea v y
ca r db oa r d. T he t a p e sh o ul d b e of t h e re m ova b le t y pe , n ot
ma sk in g ta pe . U se a d u s t bl o we r to re m ove a n y pa r t ic les , h a i r
o r d us t off t he s u r f a ce o f t h e pa pe r .
C O A TI N G L I G H T W E I G H T P AP E R S AN D F A B R I C :
L ig h t wei g h t pa pe r ma ke s i t di ff ic u l t t o coa t e ven l y d ue t o t he
pa pe r b uc k lin g. T h e fo ll o win g me t h o d i s u se f ul a l so when
coa t in g la r ge r p r in ts a n d fa b ri c. T h e foll o wi n g me t h od of
st re t c h in g o ve r co m es t h ese p ro bl e ms .
1 . L ea ve p len t y o f s pa ce a r o un d t he i m a g e t o a l lo w f o r t he
ta pin g d o wn of t he pa pe r . Pa pe r bo r de r s sh o ul d be a bo u t
7 5 m m la r ge r t ha n t he n e ga ti ve .
2 . Soa k t he pa p e r in wa r m wa te r fo r 5 min u te s.
3 . Re m ove f ro m t ra y a n d a l lo w t he wa t e r to d ri p ba c k in to
t he t ra y f or a f e w m o men ts .
4 . Pla ce on a g la ss s u rf a c e la r ge r t ha n t he pa pe r a n d bl o t
d r y wi t h c o t to n t o wels .
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
3 6
5 . Ta p e d o wn a ll s id e s wi t h g u m m ed ta p e, t hen da b ov e r
ca re f ull y a ga in wi t h c o t ton pa pe r to wel s.
6 . Wh en mo s t o f t h e da m pn e ss
fin i s h d r y in g wi t h a ha i r d r ye r.
is
g on e
7 . L ea ve t h e pa pe r o n t he g la ss fo r b o t h of
t he s ol u ti on c oa t in gs. S to r e in a d a r k o r
di m lig h t pla ce wh e n d ry in g t he s en si t i ze d pa pe r .
N B: F a b r i c s ho u l d b e 1 0 0 % c o t ton , wa s h a n d d r y be fo re u sin g
to re m ove a n y si z in g e tc . I t is ea sie r t o su b m e rge t h e fa b ri c in
t he sa lt s ol u t ion a n d t h en ta pe i t do wn . S il ve r n i t ra t e is
a p pl ie d wh en d r ie d , b ut st il l t a p ed do wn , wi t h a s pon ge br us h .
S A L T C O A TI N G
T his ca n b e ca r r ie d o u t un de r n o r ma l l i gh t in g .
Ro d me t h od of a p pl ica t ion f o r a n 8 x 1 0 in c h p rin t :
1.
D ra w u p 2 m l o f so l u ti on in t o t h e s y rin ge .
2.
2 0 m m in f r o m t he ma r ke d i ma ge a rea g en t l y di sp en se a l l
t he s ol u t ion on to t he pa pe r in a l in e , st o pp in g 2 0 m m f ro m
pa pe r e dge .
3.
Gen tl y p la c e t he r od in t his l in e of fl u i d, wi t h ca r ef u l
si de wa r d mo ve men ts a l lo w t he f l ui d to ev en l y d is pe r s e
a lon g t h e f ul l len gt h o f t h e r o d .
4.
L if t t h e r o d ov e r t h e sol u t ion s o t he r od s i ts b e t ween t he
pa pe r e dge a n d t he sol u t ion .
5.
P us h t h e s ol u t ion t o t he o t he r en d of t he p a p e r , a t l ea s t 2 0
m m be yon d t he i ma ge a rea . T he p us h s h o ul d b e a t a
con s ta n t s mo o t h st ea d y r a t e wi t h ve r y li t t le p re ss u re . T h i s
sh o ul d ta ke a bo u t t en s ec on ds .
6.
Ch ec k fo r un coa te d a r ea s , i m m e dia te l y d ra g t he s ol u t io n
ba c k ov e r t h ese a re a s t o a vo i d u n ev en coa t in g .
7.
Aga in li ft t he r o d o ve r t he s ol u t ion so t he ro d si ts be t we e n
t he pa pe r e dge a n d t he l on g po ol of s ol u ti on .
8.
Gen tl y p u s h t h e so l u ti on to t he o p p osi t e en d o f t h e pa pe r .
9.
If t he pa pe r is e ve n ly co ve re d wa it f o r 3 0 se c on ds wh i l e
t he s ol u t ion a bs o r b s i n t o t he p a p e r.
1 0 . T he re m us t be en o ug h s ol u ti on to c on tin ue p us h in g a t
lea s t 4 mo re t i mes s m oo t h l y a c r oss t he pa pe r .
1 1 . T he re s ho u ld be n o p u d d l es o f so l ut i on o r a rea s w i tho u t
co ve r ag e .
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
3 7
1 2 . An y ex ces s ca n b e re m ov ed gen t ly wit h a pa pe r t o we l ,
a vo id in g t he i ma ge a rea or h ol d t h e pa pe r b y a c o rn e r a n d
a ll o w a n y e xc ess t o r un o ff .
1 3 . Ha n g o r la y t he pa p er so l u ti on si de u p to d r y . A ha i r d r ye r
on t he wa r m se t tin g wil l s pee d u p t he p r oc ess . Kee p in g t he
d r ye r 1 0 c m a wa y f r o m t h e pa pe r s u r fa c e.
Wh en us in g a h ig he r pe r cen ta ge o f g el a ti n in t he sa l t so l u ti on
en s u re t ha t t h e pa pe r a n d t h e so l u ti o n a re hea te d to a t
lea s t 2 0 ° C t o 2 2 °C . T hi s s t op s t he ge la t in se t tin g a n d
„d r a g g in g ‟ un e ven l y d o wn t he pa pe r . In c rea sin g t h e
q ua n ti t y of f l ui d a p pl ie d to t he pa pe r e a ses t h i s p r o ble m .
Fo r exa m p le , a 8x 1 0 i ma ge n o r ma ll y re q u i res 2 m l o f
sol u t ion , t he re fo re i n c rea s e t h is to 3 ml .
B r us h me t h o d of a p pl ic a t io n :
P re pa re t he pa p e r t he sa m e wa y a s t h e sa l t c oa tin g.
1 . Po u r 2 0 ml o f sa l t so l u ti on in t o a di s h wi de en o u g h to
a c co m m o da te t he br us h wi d t h .
2 . Al lo w t h e b r us h to a bs o rb t he m oi s t u re .
3 . Re m ove e xc ess o ff t he b r us h .
4 . Pa in t on t h e so l u ti o n by r un n in g t he b r us h u p a n d d o wn t h e
pa pe r , ov e rla p pin g ea c h s t r o ke sl ig h t ly .
5 . En s u re t he re a re n o ga p s.
6 . T u rn t he pa pe r 4 5 ° a n d re pea t t he b r us h in g , re pea t t he
t u rn i n g a n d c oa tin g a f u r t he r 2 ti me s .
7 . T he re s h o ul d b e n o p u dd les o r a r ea s n o t c ov e re d.
8 . Ho ld t he pa pe r b y a c o rn e r a n d a l lo w a n y ex ces s t o r un of f .
9.
Ha n g to d r y h a n g o r pla ce t he p a p e r so l u ti on s id e u p .
1 0 . Yo u ca n u s e a ha i r d r ye r on t he wa r m se tt in g t o sp ee d up
t he d r yin g , ke ep in g t he d r ye r a t lea s t 1 0 c m f r o m t h e pa pe r
su r fa ce .
Al lo w t h e s ol u ti on to soa k in be fo re u sin g wa r m a i r t o d r y a s
t hi s wil l gi ve a mo re con sis te n t e ven su r fa ce . Exc ess iv e hea t
wh i le s t il l q u i te d a m p wi ll d r y t h e sa l t on t he s u r fa ce lea vin g
sa l t c r ys ta l p a t c h es . T he sa l te d pa pe r wi l l ke e p in def in i te ly .
M a ke s u re t he p a pe r i s c o m ple t el y d r y b ef or e a d d in g t he
sen si t ise r .
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
3 8
A L B U M E N C O A TI N G
Al b u men is n o t a s ea sy to co a t a s pla in sa l t . B ub b les a n d
lu m p s c re a t e da r k s po t s a n d ci r cl es . U n even s t rea k s wil l s h o w
a s di ff e rin g den si ti es in t h e fin a l p r in t .
o
In c rea s e t he a m o u n t of s o l u ti on y o u a p pl y . T he
exce ss so l u ti on a l l o w s c on t ro l o ve r t he s mo o t hn e ss
of t he c oa tin g .
o
A dd in g 0 . 5 % o f we t t in g a g en t to t h e a l b u men so l u ti on
t he o re ti ca ll y re d u c es a i r b u b ble s on t he s u rfa ce of
t he pa pe r a n d f o r ms s mo o t he r coa t i n gs . 39 I fo un d
t he re wa s n o t a sign if ica n t d iff e re n ce wi t h t h e
we t t in g a gen t .
o
Re m ove a n y e xc ess a lb u m en a r o un d t he ed ges o f t h e
p rin t ; t he e xc ess fo r ms h a r d l u m ps t ha t ma ke i t
di ff ic u l t to m ove t he r od even l y a c r o ss t h e pa p e r
wh e n a p pl y in g t he s ilv e r n i t ra te s ol u t io n .
S Y R I N G E : I f 2 m l is u sed on a n 8 x 1 0 sa lt
p rin t , in c rea s e t hi s to 3 t o 3 . 5 ml of
a lb u m en . M ove t he ro d sl o wl y a n d
sm o o t hl y u p a n d d o wn t he pa pe r . W h en
b u bb les a p pea r s to p c oa tin g a n d a l lo w t h e ex ces s t o r u n o ff
t he pa pe r e dge b y h ol din g u p b y on e co rn e r .
B R U S H I N G . A ll o w p l en t y o f s ol u t ion s o yo u ca n sl o wl y a n d
gen tl y b r us h t he so l u ti on on t o t he pa p er .
D R Y I N G . A bo u t
a lb u m en .
3 0°
C
wi ll
c re a te
a
glo ss ie r
fin is h
for
th e
T he si lv e r n i t ra te c oa tin g se ts o r coa g u la t es t he f i rs t c oa ti n g
so t he re i s n o n ee d to ha r den t h is un le s s a se c on d c oa t of
a lb u m en is des i re d . H o we ve r a se con d coa t i n c r ea se s t he
su r fa ce gl os s , t he re b y p r od u c in g a n ex t ra b ril lia n c e t o t h e
a lb u m en p r in t. Ha r d en in g i s ess en tia l t o a v oi d s of ten in g t he
fi rs t a l b u m en c oa t wh i le a p pl y in g t he s ec on d . T h e d r ie d
a lb u m en is wa t e r so lu b le un ti l ha r de n e d wi t h :
o
o
o
Ti me
Sil ve r n i t ra t e
Al co h ol
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
39
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
3 9
U n sen s i ti ze d a l b u m en wi l l s to re in d ef i n it el y in a n a i r t ig h t
con ta in e r in co ol co n di t ion s wi t h rela t i vel y s ta bl e
te m pe ra t u r e s a n d lo w r e la ti ve h u mi d it y .
S E N S I TI S I N G TH E P A P E R
Ea r lie r me t h o ds of sen si t is in g we re pe rf o r me d b y fl oa tin g t h e
sa l te d pa pe r on t h e su r fa ce of a ba t h of si lve r n i t ra t e s ol u t i on .
T his da ng e r ou s p ra c ti ce a n d wa s te f ul me t h o d a s i t c on s u me s
la rge a mo u n t s of s i lve r n i t ra te . I s t r on gl y s ugg es t t h e re is n o
phy si c al c on t ac t w i th si l v er ni tr a te . T he g la s s ro d a n d t he
sy r in ge m e t ho d of coa t in g wi l l e va d e a ll co n t a c t wi t h t he
sil ve r s ol u ti on .
A s y rin ge ( wi th o ut t he needl e ) ma k e s it ea s y t o c on t ro l t he
a m o un t o f si lve r n i t ra te s ol u t ion a p pl ie d. E ven t h o ug h t he r e is
n o p h ys ic a l c on ta c t wi t h t he s il ve r n i t r a te yo u s t il l m u s t we a r
p ro t ec t ive gl ove s. D o n o t t o u c h t h e s y rin ge ti p on t he s a lt e d
pa pe r . T hi s wi ll con ta m in a te t he res t of t he s il ve r n i t ra te when
d ra wi n g mo r e so l u ti on in to t he s y r in ge fo r t he n ex t p rin t .
U se t he sa me q ua n ti t y of si lv e r n i t ra te so l u ti on a s t he sa l t
sol u t ion . Fo r e xa m p le if 2 ml o f sa l t s o lu t ion wa s u se d, us e 2
m l of t he s il ve r n i t r a te s ol u t ion .
To a pp l y t h e si lve r n it r a t e:
1.
En s u re sa l t ed pa pe r is co m p le te l y d r y .
2.
Ta ke a c lea n g la ss r od .
3.
P u t on g lo ves .
4.
Wo r kin g un de r lo w in ca n des cen t
sol u t ion in to t he s y rin ge .
5.
O n t he pa pe r 2 0 m m o u t f r o m wh e re t he i ma ge st a r t s
gen tl y di sp en se a l l t h e so l u ti on on t o t h e pa p e r in a
st ra ig h t l in e , s to p pi n g 2 0 m m in f ro m e dge .
6.
Pla ce t he r o d c a r ef ul l y on t he fl u i d a n d wi t h gen tle
si de wa r d m o ve men ts a l lo w t he f l ui d t o ev en l y d is pe rs e
a lon g t h e f ul l len gt h o f gla ss ro d .
7.
Po si ti on t he ro d be t we en t h e pa pe r e d g e a n d t he so l u ti on .
8.
D ra g t he so l u ti on t o t he o t he r en d of t he p a p e r a t lea s t 2 0
m m be y on d t he i ma ge a rea , b u t s t o p be fo re t he e d ge o f t h e
pa pe r . T h e d ra g s h o ul d be a t a con sta n t s m oo t h s tea d y
ra te , wi t h ve r y li t t l e p re ss u re . T h is s h o ul d ta ke a b o ut t en
sec on ds . I f t h e r e a r e p a r t s o f t h e i m a g e n o t c o v e r e d b y t h e
l ig h tin g,
d ra w
t he
solution immediately drag the solution back over this area to
avoid an uneven coating.
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
4 0
9.
Aga in g en tl y l if t t h e r o d o ve r t he so l u ti on s o t he r o d s it s
be t we en t h e pa pe r e dge a n d t he l on g po ol o f so l u ti on .
1 0 . Gen tl y p u s h t h e so l u ti on to t he o p p osi t e en d o f t h e pa pe r .
1 1 . If t h e p a p e r is even ly c ove r ed wa i t fo r 3 0 s ec on ds fo r t he
sol u t ion t o a bs o r b i n t o t he pa pe r .
1 2 . T he re m us t en o ug h sol u ti on le f t on t h e pa pe r t o s m oo t hl y
re pea t t he coa t in g a t lea s t 4 t i mes .
1 3 . En s u re t he re a re n o p u dd les of s ol u t ion o r un c oa te d a r ea s .
1 4 . An y ex ces s ca n be re m ov ed gen tl y wit h a pa pe r t o wel ,
a vo id t he i ma ge a re a .
1 5 . Ho ld t he pa pe r b y a c o rn e r a n d a l lo w a n y ex ces s t o r un of f .
1 6 . To d r y ha n g o r la y t he pa pe r s ol u t ion si de u p. A ha i r d r ye r
ca n be u se d, kee p t he d r ye r 1 0 c m a wa y f ro m t he pa pe r
su r fa ce .
1 7 . D r y in da r k o r l o w l ig h t a rea .
I t is i mp o r ta n t to w a sh t he r od a f te r e ve ry co a t of s il ve r . T he
r od be co m es con ta m in a te d wi t h sa l t a s yo u a re coa t in g .
T he s t re n g t h of t he sil ve r n i t ra te sol u t ion re g ula t es t he g r a in
si ze o f t he p re c ip i ta ti n g s il ve r c hl o ri de . S t r on g e r so l u ti on s
p ro d u ce la r ge r g ra i n s t ha t a re les s li k el y t o a bs o r b in to t he
fi b res of t he pa p e r. 40
Coa tin g
c rea te s:
t he
si lv e r
n it ra te
on to
t he
d ry
s o di u m
c hl o ri de
1 . Sil ve r c hl o ri de , t h e i ma g in g ma kin g c o m po u n d .
2 . So di u m n i tr a te , t hi s m us t be wa s he d ou t o f t he p rin t
a ft e r ex po s u re.
S E N S I TI S I N G A L B U M E N P A P E R
o As wi t h t he a lb u m e n sa l t s ol u t ion , i n c rea se t he a m o un t o f
sil ve r in t he s y r i n ge o r on t he b r us h t o en s u re ea sy
a p pl ica t ion . ( 3 mls f o r 8x 1 0 s hee t ) T hi s a lso he lp s min i m is e
t he b u bb les .
o
40
Th e fi r st p us h of t he s il ve r n i t ra t e so l u ti on do wn t h e pa p er
sh o ul d b e a t a c on s ta n t s mo o t h s t ea d y ra t e (a bo u t 1 0
sec on ds on a n 8 x 1 0 s h ee t ) Wa i t 3 0 sec on ds be fo re t h e
Ibid.p56
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
4 1
sec on d „ p u s hin g ‟ of t he si lve r n i t ra te s ol u ti on t o t he en d of
t he pa p e r . Gen t l y re mo ve b ub b les b ef o re p us h in g t he
sol u t ion a c ros s t he pa pe r . T r y a t le a s t 4 p us hes do wn t he
sh ee t. S to p b ef o re t he b u b bl es lea v e a t ra i l of b ub b l es
a c ro ss t he pa pe r . E a c h of t he se b u b bl e s on t h e pa pe r wi ll
lea v e da r k ci r cle s in yo u r i m a ge .
S E N S I TI S I N G A R R O W R O O T P AP E R
A r ro wr o o t re q ui re s a s t ron ge r s il ve r n i t ra te c oa tin g b u t n e eds
to be a p pl ie d ra p id l y d ue to t h e s ta r c h ‟ s s ol u bi li t y . 41 A pp l y t he
sil ve r n i t ra te s ol u t i on a s de s c ri be d f o r t he sa l te d pa pe r .
S t or ag e of Se n si ti z e d P ape r .
T he st o ra ge of sen s it i ze d pa pe r d u lls t he p r in t , t he hig h li gh t s
los e t he i r c la ri t y a n d t h e re is los s of den s i ty . A lb u m en wi ll
sta r t to s h o w yel lo wi n g in t he hi g hl ig h ts . T he a u t h o r t he r e fo re
di sc o u ra g es s t or a ge fo r mo re t ha n t wo to t h re e h o u rs . Des pi te
t he di sa d va n ta ges rea de r s ma y wis h to us e t h e fo ll o wi n g
me t h o ds to in c re a s e s t or a ge ti m es .
41
Ibid.p57
42
Ibid. p 62
o
1 to 5 %
sol u t ion . 42
c i t ri c
a ci d
a d de d
to
the
o
Ci t ri c a c i d in t he a l b u men s ol u t ion .
o
A pp l y 2 % c i t ri c a ci d s ol u t ion on t o p a p er be fo r e
sa l tin g .
o
St o re in a c oo l, d r y , da r k a rea in b la c k p la s t ic
ba g s.
T he Sa l t p ri n t M a n u a l | C oa ti n g t he Pa p er
si lv e r
4 2
C HAPTER
7
7. P H OT OG R AM S
AN D T H E
N EG A TI V E
T a l bo t ‟s fi rs t i m ag e s w ere p ho to g r a ms m a d e b y us i n g o b je c ts
s u c h as l e a ves a n d l a c e. T hes e m a d e ne g a ti v e i m ag es o n t h e
p a p er . T h es e w e re i n t u r n e x po s e d to c re a te a po s i t i ve i m ag e.
I n 1 8 4 0 T a l bo t d is co ve re d t he c a lo t y pe n eg a t iv e w h i le
ex p er i m en t i ng o n a pro c es s he t ho ug h t m a y c o m pe t e w it h t he
D ag u er reo t y p e . A n i m ag e he ex po s e d i n t he c a m er a w as no t
v is i b l e u n t i l h e a d d e d a g a l l i c a c i d s o l u t io n to t he e x po s e d
p a p er . T a l bo t ‟s c a l o t y pe l a te n t i m ag e is k no w n as t h e f irs t
d ev e lo pe d o u t n e ga t i ve . T his s ig n i f i c a n tl y de c re as e d th e
ex po s u re t i me i n t h e c a me r a f ro m ho urs to s e co n ds . 43
Th e a bi l i t y to m a k e neg a t i ves t ho ug h co m p u t er s h as
re j u ve n a t e d m an y p ri n t i ng -o u t p ro ces s es . P ho to gr a p he r s a n d
a rt is ts w i t ho ut a c ce s s to l ar ge fo r m a t c a m er as a n d d a r kro o ms
c a n no w ex pe r ie n c e t h e ar t a n d cr a f t o f th es e t h e e a rl y
p ho to g r a p h ic p ri n t p ro c es s es .
PHOTOGRAMS
T he ea r lie st p h o to gra p h i c i ma ges c re a te d we r e p h o to g r a m s .
T he i ma ge a c hi eve d b y si m pl y pla c i n g a n o bj ec t on to t he
sen si t i ze d pa pe r s u rf a c e a n d e xp os i n g i t t o l ig h t . O f ten
p ho t og ra m s a re o ve rl o ok ed d ue t o t h e exp os u re p ro b le ms a n d
“a r t y” or j uv en i le sti g ma a t ta c he d. O bj ec t s ha ve va r yin g
den s i t y a n d ca lc u la tin g t he ex p os u re ti me ca n be p r o ble m a ti c .
U su a ll y wi t h p ho t og ra m s it is n o t p oss i bl e t o c he c k ex po s u re s
wi t h o u t ris k o f m ov in g t h e ob je c t . T he co lo u r , s ha pe a n d
di m en s i on o f t he o bj ec t wi l l ha ve a n a ffe c t on ex po s u re a n d
p rin t co lo u r .
o
Gla s s o b je c ts s uc h a s va ses a r e of ten n o t s u c ces sf ul in
U V l ig h t box es a s t h e l ig h t “ wr a ps a ro u n d ” t he o bje c t .
o
T h ree di m en s ion a l ob je c ts in s u n li g h t a l te r a s t he s un
m ove s.
o
L ig h t we ig h t ma te r ia ls ex po se d o u ts i de n eed t o b e fi r m l y
fixe d in ca s e of wi n d mo ve men t .
S c h a a f , L . J . ( 1 9 9 6 ) R e c o r d s o f t h e D aw n o f P h o t o g r a ph y T a lbo t 's N o t e bo o k s P & Q ,
U n i v e r s i t y P r e s s C a m b r i d g e , C a m b r i d g e G r e at B r i t ai n .
43
T he Sa l t p ri n t M a n u a l |
4 3
o
Col o u rs o f i te m s ma ke a di ff e ren ce to ex p os u re t i me .
Re d i t e ms fo r exa m pl e ta ke m o re ti me to ex po se t ha n
ye ll o w.
T H E S A L T P R I N T N E G A TI V E
O ft en t he fa i l u re t o p r o d u ce q ua l i t y sa l t p rin t s c o me s f r o m
un s u i ta ble n ega t ive s. T h e i dea l sa l t o r a lb u m en p rin t n e ga ti ve
ma y n o t p ro d u ce q ua l i t y p r in ts in ot h e r p r in t p r oc es ses .
A t te m p tin g t o p r o d u ce a n ega ti ve f o r va ri o us p r in tin g -o u t
p ro ce sse s o r p r o ce ssin g - o u t pa pe r s m a y c o m p ro m is e ea c h o f
t he p ro ce sses .
T he lon g t on a l ra n ge of sa l t p rin t s pr ov i des ex ce p ti o n a l
sepa r a t io n s
in
the
hi g hl ig h ts
and
re co r d s
mi d
to n es
pa r ti c ul a rl y we ll . S ha do ws la c k t he sa me de g ree of se pa r a ti on ,
ma y l o ok m u d d y a n d l a c k de ta i l. A hi g h pe r cen ta g e o f s ha do w
a rea i n a n ega ti ve ca n ma ke t he en t ir e i ma g e a p pea r f la t .
Exp os in g f o r t he s h a do ws is t he re fo re c ri t ica l . T he re m us t b e
de ta il in t he s ha d o ws a n d hi g hl ig h t s wi t h a den si t y ra n g e of
1 . 8 t o 2. 2 (a t lea s t 7 s t op s la ti t u de ) .
Sa lt pr in ts d o n o t re q u i re a hi g h c on t ra s t n ega ti ve . T he
n ega ti ve m u s t be d en se wi t h in f o r ma ti on f r o m t h e s ha d o ws to
t he hi g hl ig h ts . A l o w c on t ra s t n ega t i ve wi ll p r o d uc es a fla t
p rin t b u t h ig h c on t r a st n ega t iv e s wi l l re su l t in ha rs h co n t r a st y
p rin t s, o f ten l os i n g de ta il in t he sha do ws a n d / o r t he
hi g hl ig h t s .
S uc ce ssf u l sa l t ed pa pe r p rin t re q ui re s :
1 . A n e ga ti ve wi t h a l on g t on a l ra n ge , t h e r a n ge b e t ween
t he hi g hes t a n d l o wes t den si t y p oi n t s ma x i m ise d .
2 . A n ega t iv e wi t h e n o ug h den s i t y t o a l l o w t he si lv e r
c hl o ri de to c ha n ge i n t o m e ta l li c si lv e r d u ri n g ex po s u re .
D ue t o li g h t r ef le ct in g o ff t he s u r fa c e , glos s y a l b u men p r in t s
see m to ha ve a s h o rt e r de n si t y ra n g e t ha n ma t t pa pe r s . Th e
p rin t a p pea r s a s t h o ug h i t h a s dee pe r sha d o ws a n d b r ig h te r
hi g hl ig h t s. P ro ce ss ed- o u t pa p e rs ha v e t hi s sa me e ffe c t . A
glo ss y g ela t in -s il ve r p rin t wil l a p pea r t o ha v e d ee pe r bl a c ks
a n d wh i t e r hig h li g h ts co m pa r e d wi t h a d ull m a t t -f in i s he d
p ro ce sse d o u t p rin t . G los s y a l b u m en p r in t s ha ve a co m pa ra bl e
to n a l ra n ge t o pla t i n u m p r in ts . Sa l te d pa pe r p rin t s ex ce ed t he
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 4
to n a l ra n g e of pla t in u m. 44 Th is i s d ue to t he se lf ma sk i n g
effe c t . T h e si lve r c hl o ri d e c on v e r t s to me ta ll ic si lve r d u r in g
exp os u re t h u s b lo c kin g t he s ha do w a rea s ( lig h t pa r t o f t he
n ega ti ve ). T h is sl o ws t he ex p os u r e a llo win g t he h ig h li g h ts
(d en se / da r k p a rt o f t h e n ega t iv e) t o con t in ue p rin t in g . T he
self - ma s k in g g iv es p rin t s a gra da t ion o f lig h t to n es wh i le st il l
h ol din g go o d s ha do w de ta il . Co r r e c t n ega t ive den s i t y is
i mp o r ta n t f o r t he hi g hl ig h t s so t h ese lig h t e r ton e s a re n o t
ove r -ex p ose d .
T he sa l te d pa pe rs a n d ma t t (s in g le c oa te d) a l b u men p r i n ts
re q u ir e mo r e re d uc ed s il ve r to m a ke t he a p pea ra n ce of b la c k
in t h e s ha do ws . T h is is a c h iev e d b y l on ge r e xp os u r e t i m e s,
t he re fo r e t he n ee d fo r a den se r n ega ti ve .
T he p la in sa lt ed
p rin t wi t h o u t a bin de r is t he fla t t es t i n a p pea ra n ce ; t he r e fo re
it r eq u i res t h e g r ea t es t den s i ty r a n ge in t he n ega t iv e t o
a lle via t e t h is l oo k .
T Y P E S O F N E G A TI V E S :
Al t h o ug h n e ga ti ve s fa ll in to t o t wo ma jo r g ro u p s , a n a l og ue
a n d d igi ta l , t he se g r o up s do in te r t win e . An a n a lo g ue n ega t ive
ca n be p ro d u ce d f ro m a di gi ta l fi le a n d a n a lo g ue n ega t ive s a re
di gi t ise d to c rea t e i n k je t n e ga ti ves . T h ey a ll off e r a d va n ta ges
a n d ha v e d isa dva n t a ges .
A N A L O G U E C O N TI N U O U S T O N E F I L M N E G A TI V E S
A dva n ta ges :
o
Ne ga ti ves ca n p r ov i de a n ex ce llen t con t in uo us t on e .
o
De ve lo p men t con t r ols ca n c r ea te t he ext ra den si t y f o r
sa l t p r in ts .
o
Sil ve r n ega ti ve s b l oc k in g po we r s a r e gr ea te r t ha n t he
bla c k dy es o f in kj e t pr in te rs .
D isa dva n ta ges :
o
Fil m ma y n o t be rea di l y a va i la bi li t y .
o
Re q ui re a da r k ro o m fa c il i ty .
o
3 5 m m a n d me di u m fo r ma t f il m s n ee d to be en la rg ed b y
mea n s of in te r - n eg a ti ve s o r rev e rse p ro ce ss in g . T h ese
ma te r ia l s a re ex pen siv e. D us t ca n b e a c u rse .
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p69
44
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 5
T he n u m be r o f bla c k a n d wh i te f il m s a va i la b le on t h e ma r ke t
to da y ha s r ed u ce d con s i de ra bl y d ue t he i n c r ea se of di gi ta l
ca p t u re ca me ra s . S he et fi l m a va i la bil i t y in A us t ra lia is q ui t e
li m it e d. (Se e s up p li er l is t ) T he c ho ic e is wi de r in 3 5 m m a n d
1 2 0 ro ll fi l ms . T he i n te rn a ti on a l ma r ke t of fe rs a m o re
ext en s ive ra n ge .
Fil m ex p o s u re
fol lo win g :
and
t on a l
ra n ge
ca n
be
con t r ol le d
by
the
1 . L ig h tin g o f t he s u b j ec t .
2 . T he t y pe of f il m us e d .
3 . T he d eve lo p m en t t i me a n d a g i ta ti on .
4 . T he t y pe a n d s t ren g t h o f t h e de ve lo pe r .
Th e sa l t p r in t n ega ti ve m us t be ex po se d fo r t he s ha d o ws . T he
st re n g t h of t he de v elo pe r s ol u ti on is do u b le d t o p ro vi de t h e
den s i t y.
T h ro u g h
exten si ve
tes t in g
I
ha v e
fo un d
t he
co m b in a ti on o f I lf o rd ‟s HP 4 f il m a n d PM K de vel o pe r to
p ro d u ce t he bes t sa lt p rin t n e ga ti ves t o da te .
I L F O R D F P 4 F I L M 1 2 5 I SO
T his fi l m wi l l c r ea t e a wi de t on a l ra n g e ex ten de d b y
t he lo w fo g ba se o f t he f il m . U s e t h e 1 2 5 ISO ra t in g
a n d ex po se f o r t h e sha d o ws .
PMK DEVELOPER45
S ol u ti on A
D is ti lle d wa te r a t ro o m t e m pe ra t u re
M et ol
So di u m bi s ul fi te
P y ro ga l lo l
Wa t e r t o m a ke
S ol u ti on B
D is ti lle d wa te r a t ro o m t e m pe ra t u re
So di u m m e ta b o ra te
Wa t e r t o m a ke
7 5 0 ml
10 gm
20 gm
100 gm
1 0 0 0 ml
1400
600 gm
2 0 0 0 ml
M et h o d:
S t oc k S ol u ti o n A
1 . Weig h o u t t h e so di u m bis u lf i te .
45
Hutchings, G. (1992) The Book of Pyro, Bitter Dog Press, Granite Bay, CA. p13
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 6
2 . A dd a pi n c h o f t h e so di u m bis u lf i te t o t h e 7 5 0 ml o f wa t er
a n d se t t he re ma in d er a s i de .
3 . A dd t he me t ol a n d s ti r un t il c o m pl e tel y di sso lv ed .
4 . A dd re ma in i n g s od i u m bis u lf i te , s ti r un ti l d iss ol ve d .
5 . If yo u do n o t ha v e a ven t ila t in g ho o d, p er fo r m t he f oll o wi n g
o u tsi de .
6 . P u t on g lo ves , ma s k a n d ey e p r o te c ti on .
7 . M ea s u re o u t t he p y r oga ll ol a n d a d d to t he s ol u t ion .
S t oc k S ol u ti o n B
1 . D iss ol ve t he so d i u m me ta bo r a te in t he 1 4 0 0 ml of wa te r .
2 . A dd wa t e r t o m a ke 2 0 0 0 ml .
St o re in b ro wn gla s s bo t t les cle a rl y ma r ke d .
U sa ge f o r sa l t p rin t n ega ti ve s on l y :
Sal t pri nt ne g a ti ve :
1.
Hea t wa te r 5 0 0 ml t o 2 2 ° C .
2.
A dd 1 0 ml pa r t A .
3.
A dd 2 0 ml pa r ts B .
4.
P ro ce ss f il m wi t h co n ti n ua l a g i ta ti on f o r 1 2 m in u te s .
5.
St o p ba t h 3 0 se c on d s (n o r m a l a ci d s to p ba t h ) .
6.
Fix fo r 5 m in u te s a gi ta ti on fo r 3 0 se con ds e ve r y m in u te .
(S ta n da r d rea d y- ma de a m m on i u m t h ios ul fa te f ixe r ) .
7.
D o n o t ta n t he n ega ti ve a s o f ten s ug ges te d b y pla cin g ba c k
in t o dev el op e r a f te r f ixin g . T hi s fla t t e n s t he t on es fo r t h e
sa l t p r in t.
8.
Wa s h fo r 1 mi n u te .
9.
Pla ce in a ba t h of 1 % c lea rin g a ge n t f o r 2 m in u tes ( 1 0 g m
so di u m s u l p hi te i n 1 0 0 0 ml wa t e r) .
1 0 . Wa s h fo r 5 mi n u te s .
1 1 . A d r o p of we t t in g a gen t in 1 0 0 0 ml wa t e r f o r 1 m in u te s t o ps
st re a k ma r k s .
O the r Fi l m s
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 7
1 . I L F O R D H P 5 4 0 0 ISO . Si mi la r q ua li t ies t o t h e I lf o rd FP 4 fil m ,
b u t wi t h o u t s u c h a clea r fi l m ba se . P r oc ess a s a b ov e b u t
in c re a se t he dev el o p men t ti m e t o 1 2 m in ut es
2 . F O M A P A N C L A S S I C 2 0 0 I SO . T h is fi l m wo r ke d wel l wi t h si m il a r
q ua l i tie s t o t he I lf o r d F P 4 . T he ba se fo g a n d PM K de vel o pe r
wa r m ed t he n e ga ti v e ba se co lo u r . T hi s fla t ten s t he s a l t p ri n t
to n a l ra n ge . P r oc e ss t he f il m a s a b ove b u t i n c r ea s e t he
de vel o p men t ti m e t o 1 2 m in u tes .
I N C R E A S I N G TH E T O N A L R AN G E P O S T D E V E L O P M E N T
Fil m R ed u c in g Fo r m u la s p r ov i de d on l y a min i ma l i n c re a se i n
t he ton a l ra n g e .
Sele n i u m wa s s u c c essf u l a s a f il m i n ten si fy in g f or m u l a . A
sol u t ion o f 1 : 1 0 fo r 1 0 mi n ut es in c rea s ed t h e t on a l ra n ge b y 2
st o ps , d ue t o sel en i u m a d din g den si t y t o t he h ig h lig h t s .
E N L A R G I N G N E G A T I V E S I N TH E D AR K R O O M
En s u re y o u r da r k r o o m is li g h t t ig h t a n d y o u r e n la rg e r d oe s n o t
re fle c t l ig h t a ro un d t h e r oo m . T h is st o ps t h e r is k o f l ig h t
fog gin g ex pen s ive f il m . W hi te ba se d e a sels s h o ul d b e co ve re d
wi t h a bla c k s he e t of pa pe r to st o p lig h t ref le c tin g b a c k
t h ro u g h t he f il m . Th e o r t h o fi l m a n d l i t h f il m a re hi g h
con t ra s t s o d il u te d pa pe r d eve lo p er is use d t o lo we r t h e
con t ra s t.
3 5 m m a n d 1 2 0 ro ll fil m s ca n be en la r ged in t he d a rk r o o m b y
ma k in g a n en la rge d in te r- p os i ti ve t hen c on ta c t p rin t in g b a c k
to a n e ga ti ve o f t h e sa me si ze . T h is i s a t wo s t ep p ro ce ss .
In te r- p osi t iv es me t h od of en la rgi n g n e ga t iv es :
o
U sin g Il fo r d O r t h o Pl u s fi l m. T his m u s t b e u se d un d e r a
re d sa fe li g h t .
1 . Pla ce t he 3 5 m m o r 1 2 0 ro ll f il m in t he en l a rge r
a n d c he c k t h e f o c u s e t c , a s fo r n o r ma l da r k ro o m
p rin t in g .
2 . U se tes t s t ri ps t o f in d t he co r r ec t e xp os u r e.
P ro ce ss t h is i n d il u te d pa pe r de ve lo pe r . S of t
de vel o pe rs s u c h a s Ko da k Sel ec t ol
un d il u te d wi ll
giv e go o d h ig h li g h t a n d s ha do w de ta il .
3 . A dj u st t h e ra ti o o f t he de ve lo pe r t o con t r ol t h e
con t ra s t.
4 . Wh en t h e n e w po si ti ve i s d r y pla ce t hi s on n e w
te st s t r i p fi l m .
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 8
5 . Exp ose de te r m in e t he ex p os u re ti m e .
6 . Con ta c t p r in t t h e n e ga t iv e.
7 . Tes t t h is n e w n eg a t ive to en s u r e yo u h a ve n o t lo s t
t he ton a l ra n g e , o r ga in e d to o m uc h co n t ra s t .
o
U sin g M a c o Gen i u s fil m : T h is ca n be us ed un de r a re d
sa fe l ig h t .
1 . Pla ce t he 3 5 m m o r 1 2 0 ro ll f il m in t he en l a rge r
a n d c he c k t he f o c u s , e t c . a s f o r n o r m a l da r k r oo m
p rin t in g .
2 . U se tes t s t ri ps t o f in d t he co r r ec t e xp os u r e.
P ro ce ss t hes e in di l u te d pa p er de v elo pe r . S of t
de vel o pe rs s uc h a s K o da k S ol ec t ol
1 : 2. Fo r 2
m in u tes . Ad j us t t he ra t io of t he d eve lo pe r t o
con t r ol t he con t ra s t .
3 . Wh en t he n e w p os i t ive is d r y , p la ce t he po si t ive in
di re c t con ta c t wi t h tes t s t r ip s t o d e t er m in e t he
co r re c t ex p os u re .
4 . Con ta c t p r in t t h e n e ga t iv e .
5 . Tes t t h is n e w n eg a t ive to en s u r e yo u h a ve n o t lo s t
t he t on a l ra n ge o r t ha t i t ha s ga in e d to o m u c h
con t ra s t.
D I G I TA L N E G A TI V E S
A kin to a n a l og u e f il m , t he a m o un t o f in fo r m a ti on a n d t he
q ua l i t y o f t h e dig i t a l fi le wi l l ref le c t in t h e o u t co m e o f t he
fin a l p rin t . T h e ref o re t h e me t h o d of s ca n n in g o r ca p t u rin g a
di gi ta l i ma ge in ca me ra m u s t be c on s id er e d. A pr of ess io n a l
p ho t og ra p h ic la b o r dig i ta l b u r ea u wi ll offe r q ua l i ty s ca n n in g
se rv ic es . An 8x 1 0 n ega ti ve s ca n n e d a t 4 0 0 p pi wi l l gi ve a fil e
si ze of 3 6M B . D ig i ta l ca me ra s a r e be yon d t he s co pe of t his
bo o k d ue t o t he c o mp lex a n d con s ta n tl y c ha n gi n g ma r ke t .
Al t h o ug h n o t di s c u sse d, t he ca p t u re d i ma ge f ile s ho u l d h a ve
si mi la r q u a li t ies t o t he re fe r re d s ca n n e d fi le a bo ve .
D igi ta l n ega t iv es in cl u de :
1.
Inkjet negatives from digital files
a)
In k je t n ega t iv es
b)
In k je t s pe c t ra l n e ga ti ve s
c)
Pa pe r in k je t n ega t iv es
d)
L a s e r p r in t n ega t ive s
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
4 9
An a l og u e Ne ga ti ve s fr o m Di gi ta l Fi les
a)
Ko da k D u r oC l ea r™ s pe c t ra l n e ga ti ve
b ) I ma ge S e t te r fi l m
SP ECT R AL N EG AT IV E S :
A n a me use d t o de s c ri be f il m t ha t u ses co lo u r to
t ra n s m i t o r b lo c k d iff e ren t wa ve len g t h s rea c hin g
lig h t s en si t i ze d pa p er .
In 1 8 7 3 W .H . V og el dis c ov e re d sen s it iv i t y to
gr een wa s en ha n ce d by a d d in g ye ll o w d ye t o
Salt print
co ll o di on pla t es . He s uc ce ss f ull y t ri ed r e d to Spectral negative
a bs o r b t he g re en l ig h t a n d g re en to a bs o r b t he re d. T his
di sc ov e r y ha d a n e n o r mo u s a ff ec t on t he f u t u r e of bo t h b la c k
a n d wh i te a n d c ol o u r p ho t og ra p h y . In b la c k a n d wh i t e
p ho t og ra p h y g reen , ye ll o w, o ra n ge a n d re d li g ht d is t o r t t he
to n e va l u es . F o r e xa m p le r ed i s di ff i c ul t to t el l a pa r t f r o m
bla c k . 46 M os t p h o to g r a p hi c p r o cess es a r e sen s i ti ve f ro m 3 0 0 to
5 0 0 n a n o me t r es in cl u di n g u l t ra v io le t , vi ole t a n d bl ue . T he
h u ma n ey e i s se n si ti ve t o t h e el e c t ro ma gn e t ic sp ec t r u m
be t we en 4 0 0 a n d 7 0 0 n a n o me t res .
Fil te r s in bla c k a n d wh i t e p h o to g ra p h y wo r k b y a bso r bin g
un wa n t ed c ol o u rs of l ig h t . T he s lo p e of t h e c ha ra c te r is ti c
c u rv e a n d t he c o n t r a st o f t he i m a ge ca n be c ha n ge d b y t h ese
co lo u r ed f il te r s . 47 Fo r exa m pl e r e d fi l te r s a bso r b a p ro p o r ti on
of t he b l ue da yli g h t . T he s pe c t ra l n e ga t ive wo r k s on t he sa me
p rin ci pa l. Co lo u r s con t r ol t he t on a l r a n ge by t he q ua li t y a n d
q ua n ti t y of l ig h t re a c hi n g t he l ig h t s e n si ti ve pa pe r. A lt h o ug h
t hi s a c ts a s a den s it y s o me wh a t si m il a r t o si lve r pa r ti cle s in
fil m , i t do es n o t ha ve t he sa me s u b tle to n a l g ra d ua ti on s whi c h
fil m o ff e rs . T his i s m o re p r ob le ma t i c i n hig h li g h ts a n d s h a do w
re gi on s .
No t e t ha t p ig m en t i n ks , u l t ra c h ro m e in ks a n d d ye - ba s e d i n ks
in in k je t p r in te rs ma ke a c on s i de r a bl e di ffe r en c e t o t h e
n ega ti ves den s i t y a n d t on a l ra n ge. G e n era ll y d y e ba s ed i n ks
p ro d u ce a wi d e r ga m u t o f c ol o u r a n d a hi g he r res ol u t ion , t he
in k si ts in t he s t r u c t u re o f t he fil m . T he pi g men t in k si t s on
Ke n n e t h - M e e s , C . E . a n d J a m e s , T . H . ( 1 9 6 6 ) T h e T h e o r y o f t h e P h o t o g r a ph i c P r o c e s s ,
The Macmillan Company, New York.
46
S t r o e b e l , L . , C o m p t o n , J . , C u r r e n t , I . a n d Z a k i a , R . ( 1 9 8 6 ) P h o t o g r a ph i c M at e r i a ls a n d
Processes, Butterworth Publishers, Stoneham, MA, USA.
47
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
5 0
t he s u r fa ce o f t he fil m . P ro d u ce rs of t h es e in k p ro d u c ts
a c cla i m a n ex te n d e d l ife . T h e dy e - ba s ed i n k s a bil i t y to b lo c k
U V l ig h t i s g rea te r t ha n t he pig m en t b a s ed in k s. 48
T he re a re n u me r o us a pp r oa c hes in m a k in g d ig i ta l n e ga ti ve s . I
fo un d M a r k Ne ls on ‟ s P re c is io n D ig i t a l Neg a t i ves bo o k u se fu l .
His s y s te m e m po we rs yo u t o c us t o m ise yo u r co m p u te r s ys t em ,
to c re a t e n eg a t iv es in a n u m be r o f o u t p u t m od es t ha t wi l l s ui t
yo u r pa r ti c u la r p ro ces s . T h is in c l ud es in k je t , i ma g e se t te r o r
Ko da k D u r a c lea r ™. T he s te p - we d ge t ha t ca n be p u r c h a sed
wi t h h is bo o k is a v a l ua b le to ol .
TRANSMISSION STEP WEDGES
T ra n s m iss ion s te p- we d ges a i d in ton a l ra n g e co m pa r is on s
a ga in s t n ega t ive s. B y e x po s in g t h e ste p - we dg e b esi d e t he
n ega ti ve i t hel ps t o in d i ca te t h e t on a l ra n ge in t h e ex p ose d
p rin t , a s sis t in g in ca l c ul a tin g f u t u r e ex pos u r es . T he st ep
we d ge is f ul ly ex po sed wh en t h e f i rs t s te p is t he sa me d en si t y
a s t he ex pos e d pa pe r o u ts id e t he n ega t i ve a re a . T h is s ho u ld be
j us t b ef o re br on zi n g o c c u rs . T h is wi ll he l p t o fin d :
o
T he t on a l sca le o f t he ex po se d pa pe r in di ca te d by
t he n u m be r o f se pa r a te s t ep s vi si bl e .
o
If t he n e ga ti ve ha s t he sa m e ton a l s ca l es a s t h e s te p
we d ge .
T ra n s m iss ion s te p- we d ges a ls o kn o w n a s g r ey s ca l es o r st ep
ta bl et s . T hes e a re a va i la b le i n a n u m b e r o f s te ps b u t t he m os t
co m m on l y us ed i s 2 1 s te ps . T hi s is a s t ri p o f fil m in s t ep s o f
exp os u re s, ea c h s te p in c rea sin g t he de n si tie s b y 0. 1 5 . T h ese
a re a va i la ble f ro m St o uf fe r o r t he y ca n b e c r ea te d on yo u r
co m p u te r wi t h P ho t os ho p ™ a n d p r in te d on cl ea r fi l m s u c h a s
Ag fa Co p y J e t o r Pi c to r i co T S P 0 0 usin g a n in k je t p rin te r .
As wi t h fi l m p rin t in g t he e m u ls ion to e m ul si on r ule st il l
a p pl ies . F li p t he i m a ge ho r i zon ta ll y be f o re yo u p r in t t he in k je t
n ega ti ve t o a v oi d l os s of s h a rpn ess in t he p rin t . T his ca n be
ca r rie d o u t in P ho t os ho p ™ o r t he p r in te r ‟s p ro pe r t ies c us to m s
se tt in g s.
N e l s o n , M . I . ( 2 0 0 4 ) P r e c i s i o n D i g i t a l N e g at i v e s : F o r S i l v e r & O t h e r A lt e r n at i v e
Processes, Mark I Nelson.p52
48
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t ive
5 1
D E N S I TY R E A D I N G S O N A D E N S I TO M E TE R
Den si t y i s t he mea su r e o f li g h t t ha t pa s ses t h r o ug h t he
n ega ti ve . ( kn o wn a s t ra n s m is si on den s i t y ). L ig h t re fl ec t in g
fr o m p rin te d ma te r ia l i s kn o wn a s re f lec t ed den si t y . T he
den s i to m e te r g ive s set va l ue s t o t h is t r a n s m it t ed a n d
re fle c te d l ig h t a l lo w in g a c on s is ten ce co m pa ri son .
Wha t eve r n e ga ti ve ty pe yo u c ho ose , do n o t b ec o me
ob ses se d . Fin d t he p ro ce ss t ha t fi ts y o u r wa y of p r in tin g. D o
n o t be t he pe rs on who en ds u p wi t h a t ec hn i ca l ly pe rf ec t
i ma ge t ha t i s de vo i d of a ll s o ul , in s p i r a ti on a n d i ma gin a t i on .
T he Sa l t p ri n t M a n u a l | P ho t og ra m s a n d t h e N ega t i ve
5 2
C HAPTER
8
8. E X P OS IN G
TH E P RI NT
T h is is t h e c h a l le ng i ng a n d e x c i t in g p a rt o f t h e p ro ces s . W h i le
ex po s i ng n eg a t i ves o n t he s e ns i t i ze d p a p er yo u c a n o bs er ve
yo ur i m ag e as i t a p p e ar s . Yo u h a ve co n tro l o ve r t he i n te ns i t y o f
t he li g h t a n d t h e l en g t h o f e x po s ur e w hi c h a f f e cts t he c o lo ur
a n d de ns i t y o f t he f i n a l p r i n t.
The s a l t p rin t re q ui r es ul t ra vi ole t (U V ) li g h t to f o r m a n
i ma ge . T he s un o r a lt e rn a ti ves s u c h a s la mp s o r t u be s e m i t tin g
U V li g h t ca n be u se d . T he l ig h t s o u r ce s ess en tia l f o r p rin tin g o u t p ro ce sse s a r e a mi ll ion ti m es s t r on ge r t ha n t hos e fo r
de vel o pe d- o u t p r o ces s es . 49 P ho t og ra p hi c en la rg e rs ca n n o t
p ro d u ce en o ug h l ig h t f o r p r in tin g - o ut p ro ce sse s .
T he co lo u r a n d co n t ra s t o f t he p r in t is in f l uen ce d
b y t he in t en si t y a n d c ol o u r of t h e e xp osin g li g h t.
A U V l ig h t b ox of f er s s ta b il it y a n d r epea ta b il i ty
wh i le s un l ig h t ‟s U V exp os u r e s a re v a r ia b le a n d
co m p lex .
S un l ig h t wi ll a ff ec t t he c ol o u r a n d con t ra s t o f t he
p rin t a s it is ex po si n g de pen d in g on :
o
Ti me of t he da y.
o
Ti me of t he yea r .
o
H u mi di t y .
o
Clo u d co ve r .
o
D i re ct s un li g h t , t hi s giv es les s c on t ra s t a s t h e ex pos u r e
is fa s t e r.
o
In di re c t s un l ig h t ,
exp os u re is sl o we r .
o
A m bien t t e m p e ra t u r e wil l a ls o a f fe ct s en si ti vi t y of t he
exp os in g p r in t wi t h l i t t le r ed u c t ion of si lve r ta k in g
pla ce b e lo w 5 ° C .
t hi s
in c rea ses
con t ra s t
as
t he
W a r e , M . J . ( 1 9 9 4 ) M e c h a n i s m o f I m ag e D e t e r i o r at i o n i n E ar l y P h o t o g r a ph s - t h e s e n s i t i v i t y
t o L i g h t o f W H F T a l b o t ' s h a l i d e - f i x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N at i o n a l
M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r ad f o r d , L o n d o n . p 1 7
49
T he Sa l t p ri n t M a n u a l |
5 3
o
D iff e ren t lev els of U V
vis i ble
lig h t
l eve ls
gen e ra te di ffe r en c e s.
and
wi ll
Al t h o ug h t he ef fe c t o f li g ht on t h e
sa l t p rin t ma xi m ise s in t he re gi on of
3 8 0n m ,
vis i ble
lig h t
up
to
a p p rox i ma te l y
6 5 0n m
wi l l
re d uc e
sil ve r c h lo r id e to me ta ll i c s il ve r . T h e sp ec t r u m bel o w 3 8 0n m
a lso r ed u c es t he re d u c ti on o f si lv e r b u t n o r ma l p ic t u r e f ra me
gla s s d oes n o t t ra n s m i t li g h t un de r 3 4 0 n m .
An ex pos u r e f ra me , a ls o ca l le d a co n ta c t p r in t
fr a me is m a d e u p f r o m 3 pa r ts ; t he f r a me , g la s s
a n d a r e mo va bl e h in ge d ba c k . T he f r a me h ol ds
t he gl a ss in p la c e a n d t h e hin ge d ba c k a p pl ies
p res s u re on t he pa pe r a n d n e ga ti v e t o s t o p mo ve m en t ,
en s u rin g t he y r e ma in in con ta c t a n d r egi s t ra ti on wh i le
exp os in g . T he fo ll o wi n g s t ep m u s t b e ca r rie d o u t in s u b d ue d
lig h t . M a k e s u re t h e sen s i ti ze d pa pe r is d r y o r t h e n e ga t ive
wi l l be de s t ro ye d wi t h b ro wn s il ve r n it r a t e s ta in s . T he gla s s
m u st b e clea n a n d f ree f r o m d us t be fo r e p la cin g t he n e ga ti ve ,
fol lo we d b y t he pa pe r on to t he gl a ss . Pos i ti on t he fil m
em u ls ion to pa pe r e m u lsi on . P la c e t h e hi n ge d ba c k o n t o p a n d
sec u r e. T u rn t he f r a me ove r a n d c h ec k b ef o re ex po sin g ma ke
su r e n o ma r ks o r d us t ha s a p pea re d a n d t h e n ega t iv e is in t he
co r re c t p os i ti on on t he pa pe r . I f y o u ha ve di ff i c ul t y
po si t ion in g t he fi l m a n d pa pe r , re mo va bl e t a p e ca n b e use d to
a t ta c h c o rn e r s of t h e f il m on to t he pa p er ; t his ca n be re m o ve d
on c e po si t ion e d . T he hin ge d ba c k a ll o ws yo u to i n s pe c t yo u r
p rin t wi t h li t t le r is k o f de r eg is te r in g t h e f i l m .
Wh en pla cin g t he exp os u r e f ra m e in t he s un li g h t, t he
di ffe r en c e in te m p era t u r e b et ween t h e co ol gla ss a n d t he
en ca s e d sen s i ti ze d pa pe r c r ea tes a h u m id i t y c ha m b e r. T his
ma y de re gis t e r t h e ima ge a s t he fil m a n d pa pe r e xp a n d a t
di ffe r en t ra te s . I t w ill g ive t he i m p res s ion of a so f t o r o u t of
fo c us i ma ge . 50
Ch ec k p rin t ex po s u re s un de r s u b d ue d lig h t . T his s h o ul d be
b ri g h t en o ug h to m a ke a de ci si on on t he ex p os u re b u t n o t so
b ri g h t t ha t i t con t in ue s to ex p ose t he p rin t . A l wa ys v ie w u n de r
t he sa me li g h tin g c on d i ti on s . T h is k ee ps a c on si s ten c y when
j u dg in g ex po s u res .
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 7 3
50
T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t
5 4
E X P O S U R E TI M E S
J u dg in g t h e ri g h t e xp os u re ca n b e di ff ic u l t. T he p r in t m u st b e
exp ose d b ey on d w h a t a p pea r s t o be t he c o r re c t e xp os u r e b y
a bo u t t wo s to p s .
Th e fix e r r e mo ve s a p p rox i ma te l y t wo t o
t h ree s t o ps of den s i t y, b u t a s t he i ma ge d r ies i t rega in s on e to
t wo s to ps in den si t y . Pe r son a l ex pe ri e n ce i s t h e be s t g ui de to
un de rs ta n d in g t h e co r re c t ex po s u re. D od gin g ca n be ca r ri ed
o u t b y c ut t in g s ha pes t o c ov e r a r ea s on t he n ega ti ve whe r e
less e xp os u r e is re q ui r e d. T hese a r e la i d on t op of t he g la s s in
t he e xp os u re f ra me a n d mo ve d f re q u e n tl y t o a v oi d dis t i n c t
o u tlin es o f t h e d o d gin g t oo l s ha pes .
L I G H T S OU R C E
TIME
UV light box*1
15 to 30 minutes
Direct Sun midday
10 to 20 minutes
Indirect sun or dull day
30 minutes to 3 hours
*1.Based on a bank of 17 Philips Actinic BL 40 watt mercury vapour
fluorescence UV tubes at a distance of 20 cm from the print. These tubes
emit UVA from 400 to 320nm peaking round 360 to 380 nm.
A di ff us e r o f o pa q ue t ra c in g pa pe r o r g r o un d g la s s c a n be
us ed ove r t he ex p o su r e f ra mes i n a U V lig h t b ox to in c r ea se
t he con t ra s t.
T he ex po s u re ti me s a re de pen den t on a n u m be r of va r ia ble s :
1 . Ne ga ti ve d en s it y .
2 . Bin de r t y pe , fo r e x a m pl e pla in sa l te d pa pe r i s fa s te r t ha n
a lb u m en b eca u se o f t he c oa tin g .
3 . A dd i ti ves s u c h a s p o ta ss i u m di c h r o ma te wi ll in c rea s e
exp os u re ti m e b u t so di u m ci t ra te wi ll dec r ea se s exp os u r e
ti m e .
R E C I P R O C I TY F A I L U R E
Sl o we r e xp os u re s i n c rea s e t he con t ra st of t h e i ma ge , f a st
exp os u re s de c rea s e t he c on t ra s t . T he ex t re me s o f e i t he r of
t he se wi ll ca use re c ip r o ci t y fa i l u re .
Hig h in ten s i t y re ci p ro c it y fa i l u re ca n oc c u r i f t h e i ma g e is
exp ose d di re c t l y t o hi g h U V c on ten t i n b ri g ht s un l ig h t . T h e
p ho t o l y sis a c ti vi t y de c rea s es a n d t he s ha do ws wi ll n o t p ri n t a s
T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t
5 5
da r k o r de n se a s i n t he lon ge r e xp os u re s . T he los s o f t he
den s i t y in t he s ha d o ws fla t ten s t he to n a l ra n ge a n d de c re a ses
t he con t ra s t.
L o w in t en si t y re c i p ro c it y fa i l u re oc c u rs w i t h a n e x t re me l y
we a k l ig h t so u r ce ; a s t he l on g e r p ri n ti n g t i me c r ea tes ve r y
sm a ll , v u ln e ra bl e silv e r pa r ti c les , t h e size o f t h e pa r ti cle s
re la tin g t o t he len g t h o f t h e ex po s u re . 51
I t ha s been fo un d t ha t o n l y a bo u t 2 % of t he o r ig in a l a p p lie d
sil ve r re m a in s on t he pa pe r . Wi t h pa r t ic les si ze s a t a b o u t on e
1 / 1 0 0 of a s il ve r ge la t in p r in t, t he sa l t ed pa pe r p r in t is a t ri s k
to a n y i m p u r i tie s. 52
SELF MASKING
T he sa l t p rin t „ sel f - ma s ks ‟ in t he s ha d o ws , t h e
re d u ce d me ta l li c si lve r bl oc k s t he da r ke r t he
sha d o w, t he s ma lle r t h e a m o un t of li gh t t ha t
rea c he s t he un ex p o sed s il ve r c hl o ri de t h r o ug h
t he re d u ce d me ta ll ic sil ve r . T h e l ig h t er a r ea s
con t in ue t o ex p os e n o r ma ll y . I t is t hi s se lf - ma s k in g
p ro d u ces t he e x ten de d ton a l ra n ge o f t he sa l t p r in ts . 53
t ha t
BRONZING
B ron z in g me a n s t he pa r ti cl es of re d u c ed me ta ll i c si lv e r h a ve
m ig ra te d to t he s u r fa c e fo r m in g a la ye r on t he s u rf a c e of t he
p rin t . T h is i s t he sa t u ra t ion p oin t whe r e t h e p r in t is ove r
exp ose d . D u rin g ex po s u re t hi s br on ze gr een i s h b ra ss y b r o wn
sh een a pp ea rs on p rin t s . 54 V er y l ig h t b ron z in g i n t h e i m a ge
wi l l d isa p pea r d u r in g p ro ce ssin g . Co n ti n uin g t h e ex p os u re
c rea te s a dee p b r on z in g wh i c h wi l l re ma in in t he i ma ge
sha d o w r eg ion s a ft er p r o c es sin g. T h is s po ils t he p r in t. I f a
n ega ti ve ha s co r r ec t den s i ty , a n d b r on zin g ha s f o r m e d in t he
ma r gin s t h e p r in t is a t i ts ma x i m u m den s i t y. W i t h s ui t a bl e
n ega ti ves e x p os u re ca n be mon i to re d b y vie win g t he ma r gin s
o u tsi de t he n ega t iv e a rea so t he re i s li t tl e n e ed to o pen t h e
exp os u re f ra mes .
W a r e , M . J . ( 1 9 9 4 ) M e c h a n i s m o f I m ag e D e t e r i o r at i o n i n E ar l y P h o t o g r a ph s - t h e s e n s i t i v i t y
t o L i g h t o f W H F T a l b o t ' s h a l i d e - f i x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N at i o n a l
M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r ad f o r d , L o n d o n . ,p 2 4
51
52
Ibid.p25
C r a w f o r d , W . ( 1 9 7 9 ) K e e p e r s o f t h e L i g h t , M o r g a n & M o r g a n , I n c ., N e w Y o r k ,
USA.p151
53
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr ac t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 7 3
54
T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t
5 6
A 2 1-s t ep t ra n s mi s sion we d ge i s use f ul t o in cl u de wi t h yo u r
p rin t wh i le ex po sin g yo u r n eg a ti ve. C h ec kin g t h e ex p ose d st ep
we d ge
a ga in s t
the
p rin t
a l lo ws
i n fo r me d
j u dge m en ts t o be ma de a bo u t f u t u re exp os u re s
a n d t he n ee ds of t h e n e ga ti ve .
W H A T O C C U R S W H E N TH E S E N S I TI Z E D P AP E R I S
EXPOSED TO LIGHT
Wh en t h e p r in t is ex po se d t o l ig h t :
o
L ig h t a c t in g o n t h e sil ve r c h lo r id e di sa ss o cia te s t h e
sil ve r a n d t he c h lo ri de a n d in s o do i n g rele a s es s ma ll
pa r ti cl es o f si lve r m eta l.
o
Si m u l ta n e o usl y f r ee c h lo r in e m ole c u les a re re lea s ed .
o
T he c hl o rin e a b so r b er s a re m ois t u r e in t he pa pe r fi b res ,
a n d t he ex ces s s il ve r n i t ra t e rea c ts wi t h t he re lea se d
c hl o rin e fo r m in g m o re si lv er c hl o ri de .
o
L ig h t c on tin u es t o b rea k d o wn t hi s n e w s il ve r c h lo r id e
c rea ti n g mo r e m e ta l li c si lve r a n d t he c y cle co n t in ue s . 55
Wi t ho u t lig h t , s p on t a n eo us re d u c ti on o f me ta ll ic si lve r c rea te s
a yel lo w co lo u r . T h is c on si s ts o f re d u ce d m e ta l li c si lve r in a
fin e l y di vi d ed s ta t e (sl o w ex p os u r e s in c rea se c on t ra s t by
c rea ti n g f in e r s il ve r ) a c ce le ra te d b y wa r m t h a n d h u m i di t y . 56 If
t he re d u c ti on of s i lve r co n tin ue s t he co lo u r wi l l c ha n g e t o
re d /b r o wn a n d fin a ll y a f te r a pe r io d o f mon t h s , t he p r in t ma y
a c t ua l l y h a ve a b ron ze d a p pe a ra n c e .
T hese t in y pa r ti c les co m b in e , f o r m in g la rge r pa r t i cle s
c he m is ts ca ll co ll oi da l . T he y a bso r b so me wa v elen g t hs b u t a re
n o t la r ge en o u g h t o a bs o rb a l l wa ve l en g t hs of l ig h t . T h is is
de pen da n t on t he i n dex of ref ra c t ion of t he b in de r in whi c h
t he y a r e d is pe r se d . F o r exa m p le , a l b u men ha s a d iff e r en t
re f ra c t io n to gel a t i n c rea t in g a d if fe r en t c ol o u r. P r in tin g -o u t
pa pe rs a f te r f ixin g be co m e ye ll o w/ r ed / b ro wn in co lo u r . Si l ve r
pa r ti cl es pa c k cl ose r t oge t h e r a s t he fix er d iss ol ve s un re d u ce d
sil ve r c h lo r id e . T he in de x o f ref r a c ti on ha s c o m pl ete l y
c ha n g ed , in so d oi n g d ra ma ti ca ll y c ha n gin g t he c ol o u r. Wh en
W a r e , M . J . ( 1 9 9 4 ) M e c h a n i s m o f I m ag e D e t e r i o r at i o n i n E ar l y P h o t o g r a ph s - t h e s e n s i t i v i t y
t o L i g h t o f W H F T a l b o t ' s h a l i d e - f i x e d I m a g e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m a n d N at i o n a l
M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r ad f o r d , L o n d o n . p 1 7
55
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 6 3
56
T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t
5 7
t he p r in t i s d r y i t a p pea rs d a rk e r a n d co l de r d ue t o t he
pa r ti cl es pa c k in g cl ose r to ge t he r . 57
A c e rt a in a m o un t o f m oi s t u re i s r e q ui re d f o r sen si t iv it y a n d
con t ra s t. O v e r- d r yi n g coa t ed pa p e r be fo re ex p os u re wi l l
re d u ce sen si t iv i ty . Exc ess da m pn es s will de st r o y t he n eg a ti ve
b y t ra n s fe r rin g t he sil ve r n it r a t e on t he fi l m. M y la r™ s h eet
( 7 5 µ m mi c ron s o r l ess ) b e t we en t h e p a pe r a n d n ega ti ve wi l l
a c t a s p r o te c ti on wi t h min i ma l lo ss o f i ma ge s ha r pn es s .
D o n o t a l lo w we t o r da m p fi n ge r s t o t o uc h t he s u rfa ce of t he
exp ose d p r in t be fo r e p la cin g i t in t o t h e wa te r ba t hs . T hi s wi l l
re s ul t in b ro wn st a i n s.
57
Ibid. p3
T he Sa l t p ri n t M a n u a l | E xp os in g t he p r in t
5 8
C HAPTER
9
9. P R OC ES S I NG
T H E P RI NT
T he w as h , to n i ng , f i xe r a n d f i n a l w as hi ng i n f l u en c e t h e co l o ur
a n d t h e l i fe o f t he p ri n t . D u e to t h e a d ve rs e e f f ec t o f t h e f i xer
o n t he co lo ur o f t h e s a l t a n d a l b u me n pr i n ts , e a rl y p ri n t ers
s e ar c he d fo r w a ys to r e - es t a b lis h d e ns i ty a n d co lo ur . He a t
to n i ng w as t h e e ar l ies t me t ho d us e d i n s al t pr i n t i ng . T h is w as
us e d b y T a l bo t a n d m a n y o t he r pr i n te rs d ur i ng t h is p e rio d .
Ne x t w as s u l p h ur to n i ng us i ng „ o l d h y p o ‟ o r f i xe r . D e co m p o s e d
s o d i u m t h io s u l f a te re le as e d s u l p h ur cr e at i ng a b ro w n is h s i lv er
s u l p hi d e fro m t he s i lv er i n t h e i m a g e. 58 Co ns e rv a to rs to d ay
w o ul d b e ho r r i fi e d a t t h e us e o f s u c h m et ho ds d ue to t he h ig h
ris k o f t he i m ag e d et er io r a t in g . D es p i te t h is , m a n y o f t hes e
e ar l y s u l p h ur t o n e d p r i n ts h a ve s ur v i ve d , i n c l u d in g t ho s e o f
t he a c c l a i me d H i l l a n d A d a ms o n .
Go l d to n i ng b e c a me co m mo n l y us e d a f t er Fr e n c h ph o t o gr a p he r
Gus t a v L eGr a y p u bl i c i s e d i ts us e i n 1 8 5 0 . E a rl y go l d to n i ng w as
co m b i ne d w i t h f ix er s k no w n as s e l d ‟o r (to n i ng f i xer b a t h ) b u t
t h is w as a l mo s t as d es t r u c t iv e as t he „ o l d h y po ‟ s u l p h ur t o ne r .
L a te r, i n 1 8 8 6 , p l a t in u m to n i ng w as a d a p t e d fro m t he
d ev e lo p me n t o f W il l i s ‟s p l a t i no t y pe 59.
M a ke s u re ha n ds a re c lea n a n d d ry be fo r e re m ov in g t h e
exp ose d p r in t. Da m pn e ss on fin ge rs o r ha n ds wi ll c r e a te a
sta in on t he i m a ge s.
T he la ye r s of a n ex po se d p r in t be fo r e p ro ce ssin g c on s is t of :
o
t he me ta ll ic sil ve r i ma ge
o
bin de r ma te r ia l s s u c h a s s ta r c h, g ela t in o r a l b u m en
o
un e xp ose d l ig h t -se n si ti ve s il ve r sa l t s (si lve r c hl o ri de ,
sil ve r n i t ra te , s il v er ci t ra te , s il ve r a lb u m en a te , e tc . ,
de pen din g on wh i c h c h e mi ca l s ha v e be e n a dd e d)
58
Ibid.p75
59
Ibid.p81
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
5 9
Al l l ig h t sen s i ti ve sa l ts a re re m o ve d t o s ta b ili se t he p rin t
lea v in g t h e me ta ll i c s il ve r i ma g e . S il v er sa l t s a re n o t so l u bl e
in wa te r ; t he c h e mi ca l rea c ti on o f s o di u m t h io s ul fa te c rea te s
a n o t he r n e w wa te r s ol u bl e c o mp lex . 60
T he g ol d , p la tin u m a n d pa l la di u m ton in g p r oc esse s a re
exp en si ve so t ri m off ex ce ss pa pe r a r o un d t he p r in t be fo re
pla c in g in t h e wa te r . En s u re t o lea ve a t a l ea s t 1 5 m m bo r de r
fo r ha n din g a n d f ra m in g .
PRE-WASH
Pla ce p rin t in wa r m wa t er , 1 8 to 2 0˚ C f o r on e min u t e wi t h
con s ta n t a gi ta t ion . Cha n ge wa te r un t il t he wh i t e c lo u d in g of
c hl o ri de i on s s u b si des . T h is ta kes a bo u t 1 0 m in u te s. Pla c e t he
p rin t s in a 1 % so l u ti on of s o di u m c hl o ri de a n d a gi ta t e fo r 1
m in u te . 61 T hi s a ss is ts in re m ov in g un e xp ose d si lv e r c h lo r id e
a n d si lv e r n i t ra te . T he p r in t fa des t o a d ull b ro wn in t his ba t h
b u t wi ll re b ui l d in t he to n e r , fix er a n d d r yin g . T he p r in t
re q u ir es a f u r t he r 1 0 min u t es o f f re q ue n tl y c ha n g in g wa t e r .
T he sa l t ba t h a s si s ts in p r ot ec t in g t he lif e a n d a c ti on o f t h e
to n in g ba t h a n d p re ven ts s ta in in g in t h e f ixe r . T h e di l u te
so di u m c hl o ri de s ol u ti on wi ll n o t d iss ol ve t h e si lve r s a l ts a s
t he s o di u m t hi os u lf a te do es . So l u ble s il ve r io n s a re ex ces s
sil ve r n i t ra te in sa l t pr in ts . T he se a re o xid is in g a n d ten d t o
rea c t wi t h ' h y p o' , u l ti m a tel y c rea tin g si l ve r s ul p h id e . T his c a n
ca use a ye ll o w/ b r o wn s ta in . Be fo re fix i n g a sa l t p r in t wi t h
t hi os u l p ha te i t is i m po r t a n t t o r e mo ve t he f re e so l ub le s il ve r
ion s . S o di u m c hl o ri de doe s t h is b y p re c ip i ta tin g si lve r
c hl o ri de wh i c h is n ot oxi d isi n g . I t t hen dis so lve s in t he
t hi os u l p ha te fi xe r w it h n o s ul p h id e fo r ma t ion . 62
If t he p rin t i s le f t si t tin g in t he wa s h ba t h d u r in g t he
fi rs t f e w m in u te s , t he ex ce ss s il ve r n i t r a te di sp e rsin g
in t o t he wa te r c ha n ge s f r o m t h e wh i te cl o u d t o b r o wn ,
fo r m in g s ta in s on t he p rin t .
D u r in g t he p re - wa s h s t ep , wh i t e cl o ud in g o f t he wa t e r o c c u rs .
T his i s t he rea c ti o n b e t ween t he ex ce ss s il ve r n i t ra te le f t in
t he pa pe r pl us va ri o us i on s p rese n t in ta p wa te r . T he cl o u din g
va rie s de pen din g on t h e a m o un t of un r e d u ce d s il ve r n i t ra te on
60
Ibid.p83
E . J . W a l l a n d F . I . J o r d a n ( 1 9 7 5 ) P h o t o g r a p h i c F ac t s a n d
P h o t o g r a p i c B o o k P u b l i s h i n g C o . , I n c ., N e w Y o r k U S A . p 2 6 1
61
F o r m u la s ,
A m e r i c an
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 0
t he pa pe r . A sa l t p rin t on l y re ta in s a bo u t 2 % o f t h e o ri gin a l
sil ve r a pp li ed t o a s he et of pa pe r . T he ba la n c e is wa s he d a wa y
o r re m ove d in f ixin g. 63 I f t he e xc ess sil ve r n i t ra t e a n d s od i u m
n it r a t e a re n o t r e m ove d t h e s il ve r n it r a t e wi l l re ta r d o r
p re ven t t on in g f r o m ta k in g p la ce . Bla c k s ta in s m a y a l so re s ul t
if ex cess s il ve r n i t ra te a n d s o di u m n i t ra te a re s ti ll p r es en t
wh e n t h e p rin t is f i xed .
TONING
No b le me ta l ton in g wi t h g ol d , pla t i n u m a n d pa l la di u m in
sepa r a t e ba t hs n o t on l y in t en si fi e s t he i ma g e b u t a lso
in c re a s es t h e l ife spa n of t he p r in t. Ton in g is es sen ti a l fo r
sta b il isin g sa l t a n d a lb u m en p rin ts . T he ma ss of m in us c ul e
sil ve r pa r t ic les o n t h e pa pe r s u rf a ce is s us ce p t ib le t o
des t r u c ti on , oxi d iz i n g in s ul p h u r o us c on d i ti on s of a n o r ma l
a t m os p he re . T h e gol d s h iel d s t h e sil ve r pa r t i cle s fr o m
oxi da t ion by fo r m i n g a co m p o un d t ha t is m o re res is ta n t . Th e
to n e rs c rea t e a li g h t sen s i ti ve c hl o ri de a s a b y - p r o d uc t of
to n in g . T h is is res o lve d b y t he fi xin g p r oc ess c o m in g a f te r t h e
to n in g .
T he t yp e o f b in de r a n d t he p rin t s u r f a ce m u st be c on s id ere d
wh e n ton in g . Al b u men re q ui re s a s t r on ge r t on in g s ol u t i on to
a ll o w i t t o pe n e t ra t e t he m o re re si lien t s u r fa c e a n d t h e re fo re
t he a m o un t o f g ol d c h l or i de in t h e to n e r i s d o u ble d . T he
po r o us s u r fa c es o f a r r o wr o o t a n d pla in sa lt e d pa pe r s wi l l t on e
fa s te r . T ri m o ff t h e ex ces s bo r de r s of t he p r in t be fo r e to n in g
to co n se r ve t he t on i n g so l ut io n s .
Gol d c h lo r i de t on e rs a re rea d y fo r us e wh en t he s ol u ti on
be co m es cl ea r . T h i s is kn o wn a s r ip e n in g . W h ile t he g ol d i s
ye ll o w i t is in a n in a c t iv e a ci d s ta te . I t ta kes ti m e f o r t he
a lk a li n i t y to n e u t r a lis e t he g ol d c h l o ri de b rin g in g i t t o a n
a c ti ve s ta te . 64
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p66
63
64
Ibid.p78
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 1
GOLD BORAX TONER 65
D is ti lle d wa te r
So di u m te t ra b o ra te ( bo ra x )
Gol d c hl o ri de 1% s o lu t ion
1 0 0 0 ml
6 gm
1 2 ml
M et h o d:
1.
2.
3.
4.
Hea t d is t ill e d wa t e r to 3 8° C.
A dd t he s o di u m te t r a bo r a t e .
A dd t he g ol d c hl o ri de .
Rea d y fo r us e wh en t he s ol u t ion i s c lea r .
T he t on e r m u s t si t fo r a pp r ox i ma te ly 1 ho u r bef o re u s e to
a ll o w t he a ci di c g o ld to b ec o me a c ti v e t h ro u g h con ta c t wi t h
t he a l ka lin e bo ra x. T he t on e r s h o ul d c ha n ge c ol o u r f ro m pa l e
ye ll o w t o c lea r a s i t bec o me s a c t ive . T h is ba t h ca n be ke p t b u t
a d di t ion a l g ol d m u s t be a d de d a s t h e t on in g ef fe c t s lo ws wi t h
usa ge . It m u s t si t a ga in a f t e r a d d i n g m o re g ol d c h lo r i de u n ti l
t he s ol u t ion i s c lea r .
SODIUM ACETATE GOLD TONER. 66
D is ti lle d wa te r
So di u m a ce ta t e
Gol d c hl o ri de 1% s o lu t ion
1 0 0 0 ml
10 gm
1 0 ml
M et h o d:
1 . Hea t d is t ill e d wa t e r to 3 0° C.
2 . A dd t he s o di u m a ce ta te .
3 . A dd t he g ol d c hl o ri de .
T he so d i u m a ce ta t e ton e r m u s t si t f o r a b o u t 2 4 ho u r s to
„ ri pen ‟ bef o re us e 67 to a ll o w t he a c id i c gol d t o b ec o me a c t ive
t h ro u g h con ta c t wi t h t he a l ka l in e a ce ta te . T he to n e r s h o ul d
J a m e s , C . ( 2 0 0 2 ) T h e B o o k o f A lt e r n at i v e P h o t o g r a p h i c P r o c e s s e s , D e l m ar , N e w Y o r k .
p96
65
F a r b e r , R . ( 1 9 9 8 ) H i s t o r i c P h o t o g r a ph i c P r o c e s s e s : A G u i de t o C r e at i n g H a n d m a de
Photographic Images, Allworth Press, New York. p39
66
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p79
67
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 2
c ha n g e c ol o u r f ro m pa le ye ll o w to clea r a s i t be co m es a c t ive .
T his ba t h ca n b e k ep t b u t a d d it io n a l gol d m u st be a d de d a s
t he t on in g ef fe c t s l o ws . 1 to 2 m in u te s in t he ba t h wi l l s h o w
c ha n g es , 3 t o 5 m in u te s wi l l s u bs ta n t ia ll y c ha n ge t he p rin t .
THIOCYANATE GOLD TONER1.68
D is ti lle d wa te r
So di u m t h io c ya n a te
Gol d c hl o ri de 1% s o lu t ion
5 0 0 ml
9 gm
35 ml
M et h o d:
1.
2.
3.
4.
Hea t d is t ill e d wa t e r to 3 0° C.
A dd t he s o di u m t hi oc ya n a t e .
A dd t he g ol d c hl o ri de .
T his t u rn s re d i m m ed ia tel y a n d is r ea d y fo r use wh en t h e
sol u t ion is c lea r .
T his c rea te s a m uc h co ole r co lo u r a n d sha d o w reg ion s a l m os t
a p pea r b la c k . T he i ma g es wil l fi rs t b lea c h ba c k by t he
t hi o c ya n a te . A s t he gol d is de po si te d o n t he si lve r pa r t ic le s i t
in t en s ifi es . T h io c ya n a te t on e rs c on s u m e m o re go ld t ha n o t he r
to n e rs d ue to a g re a te r s u b st i t u ti on o f t he s il ve r b y t he g ol d . 69
I t beg in s to los e t h e t on in g a b il i ty a f t er a n u m be r of p ri n ts .
T he t on e d p rin t co l o u r te n d s t o b e a bl ue bla c k .
THIOCYANATE GOLD TONER 270
D is ti lle d wa te r
So di u m t h io c ya n a te
Ta r ta ri c a c i d
So di u m c hl o ri de
Gol d c hl o ri de 1% s o lu t ion
D is ti lle d wa te r t o m a ke 5 0 0 ml
68
Ibid. p79
69
Ibid.p.76
5 0 0 ml
2. 5 g m
1 gm
2.5 gm
1 0 ml
C r a w f o r d , W . ( 1 9 7 9 ) K e e p e r s o f t h e L i g h t , M o r g an & M o r g an , I n c . , N e w Y o r k , U S A . p
156
70
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 3
M et h o d:
1.
2.
3.
4.
5.
5.
6.
7.
Hea t d is t ill e d wa t e r to 3 0° C.
A dd t he s o di u m t hi oc ya n a t e .
A dd ta r ta ri c a ci d .
A dd s o di u m c hl o ri d e .
A dd t he g ol d c hl o ri de .
T his t u rn s re d i m m e dia t el y .
A dd wa t e r t o m a ke 5 0 0 ml .
I t is rea d y f o r u se w hen t he s ol u t ion i s cle a r.
L ik e t h e t hi oc ya n a t e go ld t on e r No 1 i t wi ll on l y l a s t t he da y
t ha t i t is ma de . I t ca n n ot be re us ed . T he t on e d p r in t c o lo u r
ten ds t o be a wa r m er bla c k t ha n t hi oc ya n a te go ld t on e r N o 1 .
T his t hi o c ya n a te t on e r fo r m u la i s in cl u de d a s is less gol d
c hl o ri de in t he s ol u ti on t he re fo re m o re e con o mi ca l .
Pla t in u m T on e r 71
D is ti lle d wa te r a t 3 0° C
Po ta ssi u m c h lo r op la tin i te 2 0%
Ci t ri c a c i d
1000 ml
2.5 ml
2.5 gm
M et h o d:
1.
2.
3.
4.
Hea t d is t ill e d wa t e r to 3 0° C .
A dd t he Po ta ssi u m c hl o r op la tin i te .
A dd t he ci t r ic a ci d .
T he t on e r i s r ea dy f o r u se wh en co ole d to 2 0 ° C.
T his cr ea tes a b r o w n b la ck ton e . Do n o t ov e r- t on e a s t he r e is a
ri s k of dev el op in g ye ll o w h ig h li g h ts . I m p u ri t ies ma y d es t r oy
t he b a t h ‟s ton in g a b il i ty t he re fo r e be s u re t he p re - wa s h
re m ov e s a ll un re d u ce d s il ve r n i t ra t e a n d o t h e r i on s f ro m t he
p rin t .
J a m e s , C . ( 2 0 0 2 ) T h e B o o k o f A lt e r n at i v e P h o t o g r a p h i c P r o c e s s e s , D e l m ar , N e w Y o r k .
p99
71
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 4
PALLADIUM TONER72
D is ti lle d wa te r
So di u m c hl o ro pa lla di te 1 5 % so l u ti on
Ci t ri c a c i d
So di u m c hl o ri de
1000
2.5
2.5
2.5
ml
ml
gm
gm
M et h o d:
1.
2.
3.
4.
5.
Hea t d is t ill e d wa t e r to 3 0° C.
A dd t he S o di u m c hl o ro pa l la di te .
A dd t he ci t r ic a ci d , di sso lv e .
A dd t he S o di u m c hl o ri de .
U se wh en c oo le d to 2 0 ° C .
I t c rea tes a b r o wn bla c k to n e, b u t ca r e n ee ds to be ta k en n o t
to ov e r t on e a s t he r e is a r is k o f de ve lo pin g y ell o w hi g hl ig h ts .
I m p u ri t ies ma y de st r o y t he b a t hs to n in g a bi li t y . T he wa s h
m u st clea r t he p r in t of un -r ea c te d s il ve r n i t ra te . T hi s c rea t es a
gr e y b r o wn b la c k t o n e.
N B: T he p la tin u m a n d pa lla d i u m ton e r s do n o t gi ve t he m os t
a gr eea bl e c ol o u rs on c e r ta in pa pe r s a n d fo r m u la s . Al b u men
ma y be co m e q u i te yel lo w. S pli t t on in g wi t h go l d t on er s
fol lo we d b y p la tin u m o r pa l la di u m g iv es t he p rin t s a n ex t ra
de p t h of co lo u r . O n ly a fe w s ec on ds ma y b e r eq u i re d in t he
pla t in u m o r pa l la d i u m . Te s tin g is s t r o n gl y s ug ges t ed be f o re
pla c in g t he p r in t in to t he t on e rs .
N B: W hen s pl i t ton in g , go l d t on e r s m us t be us ed be fo r e t he
a ci d ic p la tin u m o r pa lla di u m ton e rs . T he a c id wi ll sl o w o r
a c t ua l l y s to p t he a c ti vi t y o f t he a l ka lin e gol d ton e rs . W a s h fo r
a t le a s t 2 m in u tes b et we en ea c h t on in g sol u t ion .
T he t on in g b a t h s h o ul d b e a t 1 8° C t o 2 2 °C . Pl a c e p rin t in ba t h
fo r 1 up t o 1 0 min u te s wi t h con st a n t a gi ta ti on . 2 t o 5 min u te s
wi l l gi ve y o u p r o te c ti on wi t h so m e c ol o u r c ha n ge. F o r ea c h o f
t he t on e rs y o u p la n to u se , p r in t fi ve st ep e d ge s . Pla ce a l l in
t he ton e r a n d re m o ve on e a t 2 m in u tes , t he n ex t a t 4 m in u te s,
6 m in u tes , a n d 1 0 m in u tes . I f t he te s t a re c o r re c tl y p r oc e sse d
t he t on e d s te p we dge s wi ll a c t a s a pe r ma n en t r ec o r d a n d
us ef u l g ui de f o r f u t u re to n in g .
F a r b e r , R . ( 1 9 9 8 ) H i s t o r i c P h o t o g r a ph i c P r o c e s s e s : A G u i de t o C r e at i n g H a n d m a de
Photographic Images, Allworth Press, New York. p41
72
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 5
En s u re t he re is a de q ua te b u t lo w in ca n des cen t lig h t in g to vie w
t he to n in g p r oc ess . Ab o u t 2 5 wa t t a t 1 . 0 m d is ta n ce is fi n e.
Co m pa rin g a d u p li ca te p r in t in t he wa s h wa te r bes id e t h e
to n in g p r in t hel ps see s h if ts in t h e c o lo u r . Ta ke in to a c c o un t
t he c ol o u r d if fe ren ce wh e n t he p rin t is d rie d . Ex pe r ien c e is
t he bes t g u i de . Pe n ci lle d ton in g de ta ils on t he ba c k of t he
p rin t wi ll p r ov i de i n va l ua b le f u t u re re fe ren ce . If t he n o r ma l
ti m e f o r c ol o u r c ha n ge ha s do u b le d , i t mea n s t he ton in g ba t h
is b e c o min g d ep le te d. I t i s in a c ti ve wh e n i t i s ex ha us t ed .
Kee p t h e ton in g ba t h a n d fix e r b a t h a p a r t . Des ign a t e a t ra y f o r
gol d t on in g on l y . E v en a m ic r os c op i c a m o un t o f fix e r wi ll sp oi l
t he ex pe n si ve g ol d t on e r a n d t he p rin t . 73
W a s h t he p r in t a f te r t on in g fo r a t l ea s t 4 m in u te s in ta p wa te r .
Cha n g e t h e wa te r t ra y a t lea s t 3 ti me s d u r in g t h is pe r io d to
en s u re t he to n in g sol u t ion d oes n o t con ta m in a te t h e fi xer .
Con ta m in a te d fi xe r wi l l eff ec t t he s ta b i li t y of t he p rin t .
N B: T he t hi o cy a n a te ton e r ca n c ha n ge t he fi xe r t o a s ul p h u r o us
sta t e . E x t ra wa s h in g a f te r ton in g is re q ui r e d be fo re p la c i n g in
t he f ixe r . C ha n ge t he f ix in g b a t h m o re fre q uen t l y wh en u sin g
t hi s t on e r .
T he s iz e, s ha pe a n d dis ta n ce b et ween t he sil ve r pa r ti c les a n d
t he r ef ra c ti on of m ed i u m t he y a re d i s pe rs ed in wil l i n fl u en ce
t he p r in t co lo u r . T h e g ol d t on in g m o dif ies t h e i m a ge c ol o u r b y
c ha n g in g t he si ze a n d s ha pe of t he sil ve r pa r ti c les b y
re pl a c in g s il ve r a t o ms wi t h g ol d a t o ms . T hi s en la rg e men t
ma ke s t h e i ma g e lo ok co ol e r a n d mo r e n eu t ra l in t on e . I f gol d
c hl o ri de ( I I I ) wa s us ed fo r t on i n g , t h ree a t o ms of si lv e r wo ul d
be re pl a c ed b y on e a t o m o f g ol d . 74 The i ma g e wo u ld t hen
a p pea r r e dd is h in co lo u r a n d fla t in a p pea ra n ce . 75 By ma kin g
t he ton e r a l ka l in e t hi s r e d uc es t he s ta te o f g ol d ( I I I ) t o g ol d
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p79
73
74
W a r e , M . J . ( 2 0 0 6 . ) G o l d i n P h o t o g r a ph y ., f f o t o f f i l m p u b l i s h i n g , B r i g h t o n , U K . p 1 1 0
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr ac t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p79
75
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 6
( I) . T he a t o ms o f g ol d t hen re pla ce o n e o f t he si lve r , 76 t h us
re s ul tin g in a c oo le r c ol o u r a n d t h e t on a l ra n ge in ta c t . 77
Ch ec k t he p H o f t h e t on e r to en s u re c on si s ten c y a n d t h a t i t
re ma in s a lk a li n e . I f t he ton e r is to o a l ka lin e i t wi l l :
o
L ose i t s t on in g ca pa ci t y mo r e ra p id l y.
o
Ton e m u c h fa s te r.
o
Po ssi b l y s to p ton in g if to o ex t re m e .
o
P ro d u ce bl ue g r e y c ol o u rs wh i c h a re n o t a s plea sa n t.
SELENIUM TONING
T his is a n un sa t is fa c t o r y ton e r f o r sa l t o r a l b u m en p rin t s
ei t he r be fo re o r a f t er fi xin g . T h is is d ue to t h e tin y pa r t i cle ‟s
lo w a bs o rb in g po w er ; t he si lv er s ele n id e a n d s il ve r s u lfi de
wh i c h be co m e s e m i - t ra n s pa ren t t he i ma ge a p pea r s t o h a ve
been bl ea c h e d. 78
HEAT TONING
T his is c a r rie d o u t a ft e r t h e p r in t ha s been p r oc ess e d , wa sh ed
a n d d rie d . He a tin g to n in g ca n be a c hi e ve d b y us in g a h o t ir on
wi t h p a p e r b e t ween t he p ri n t a n d t h e ir on . T h e te m pe ra t u re
ca n be se t on s il k o r co t t on . A d r y m o un tin g hea t p res s
ca p t u res t h e mo is t u re a s we ll a s a p p ly in g h ea t.
A g re a te r
to n in g eff ec t i s fo u n d usin g t h e d r y m o un tin g p re ss , t he p rin t
co lo u r c oo ls c on s i de ra bl y . In a n s we r t o m y q ue r y on t he
co lo u r c ha n g e M i ke W a r e s ug ges t s “t h e p a r t i cle s m a y be
cl u m p in g to ge t he r o r i t is l i k el y t o b e a lt e rin g t he ex t e n t o f
su l p hi din g o n t he su r fa ce of t he si lv er n a n - pa r ti cl es . T he se
co lo u r s wil l b e ve r y sen si t ive t o t he s t a te o f t he s u rfa ce . ”
THE FIXER
T a l bo t i n i t i al l y „s t a b i lis e d ‟ h is p r i nt s w it h s tro ng s o d i u m
c h lo r i d e s o l u t io ns . T h is d i d no t r e mo v e th e u ne x po s e d s il ve r
76
W a r e , M . J . ( 2 0 0 6 . ) G o l d i n P h o t o g r a ph y ., f f o t o f f i l m p u b l i s h i n g , B r i g h t o n , U K . p 1 1 0
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A .
p78
77
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 7
c h lo r i d e b u t c h a ng e d i t in to a les s s ens i t i ve fo r m . 79 So d i um
t h io s ul f a t e w as d is co ve r e d by S ir Jo h n He rs c he l i n 1 8 1 9 , h e
fo u n d i t w o ul d d is s o lv e s i l ve r s a l t s . Fo l lo w i ng He rs he l ‟s
s ug ges t io n in 1 8 3 9 T a l bo t s u c ces s f u l l y c le a re d s i l ve r c hlo ri d e
fro m h is pr i n ts t h u s s t a bi l is i ng t he m p er m a ne n t l y . S ti l l t o d a y
s o d i u m a n d a m mo n i u m t hi o s u l f a t e ar e us e d as f i xe rs i n bo t h
p ri n t i ng a n d de ve lo p i ng - o u t p ro ces s es .
T he p u r po se of f ix in g is to r e mo ve t he si lv e r c hl o ri de a n d
ot h e r lig h t -se n si t iv e s u bs ta n ce s wh i c h ma y b e p res en t. T h e p H
of t h e ba t h is i m p o r ta n t . A dd in g s od i u m ca r b on a te ma kes t h e
sol u t ion a lk a li n e t h us re d u cin g t h e bl ea c h in g e ffe c t o f t he
fixe r . T h is a l so s t op s a c id s f ro m de co m p os in g t he s od iu m
t hi os u lfa t e a n d l i be ra ti n g s u l p h u r. An a ci d fix e r ba t h s ca us e s
bl ea c h in g i n t he h ig hl ig h t s a n d mi d - to n es by a t ta c kin g t he
fin e s il ve r me ta ll ic pa r ti cle s . 80 T he rea son c o m m er c ia l f ix er s
a re n o t s ui ta bl e fo r sa l t p r in t in g.
FIXER
Wa t e r
So di u m t h ios u lf a t e
So di u m ca r bon a t e
Wa t e r t o m a ke
7 5 0 ml
150 gm
2. 5 g m
1 0 0 0 ml
M et h o d:
1.
2.
3.
4.
Hea t t he 7 5 0 m l o f wa t er t o 3 0 °C .
A dd t he s o di u m t hi os ul fa te .
A dd t he s o di u m ca r bon a t e.
A dd wa t e r t o m a ke 1 0 0 0 m l.
NB :
M a ke
t hi s
fixe r
j us t
be fo r e
us in g
to
mi n i m ise
de co m p os i ti on . S o d iu m t h io s ulf a te in i ts d r y fo r m i s r ela t i vel y
sta b le . I t i s un s t a bl e wh en d iss ol ve d in wa te r , s l o wl y
de co m p os in g to s o d iu m s ul p hi t e a n d e l em en ta l s u l p h u r. 81
U sa ge :
1 . M a in ta in t he te m pe ra t u re o f t h e fix in g sol u ti on to b e t wee n
1 8 °C to 2 0° C.
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 8 3
79
80
Ibid.p84
81
Ibid.p83
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 8
2 . U se t wo s u c ces si ve fixin g ba t h s . Ag i t a te f o r 4 min u te s in
ea c h ba t h . T he 2 ba t hs he l p t o m a xi m is e pe r ma n en c e .
3 . D ra in fo r a t le a s t 5 sec on ds be t wee n ba t hs .
T he t wo ba t hs a r e es sen tia l a s t hi os ul fa te io n s m u s t be
p res en t in e xc ess o r in s ol u b le c o m plex e s a re f o r me d wh i c h a re
on l y s ol u ble in f res h t hi os u lfa te :
1 . In t he fi r s t ba t h si l ve r - t h io s ulf a t e c o m pl exes f o r m a n d
m os tl y di sso lv e .
2 . In t he se co n d ba t h a n y re si d ua l in so l u bl e c o m pl exes a re
re m ov e d .
P ro lon ge d f ix in g c a n da ma ge t he p r in t a s t he t h i os ul fa t e
pen e t ra t es t he p a p e r f ib r es a n d be c o m es d iff i c ul t to re m o ve. 82
T he ex t ra si lve r p re sen t in sa l te d p a pe rs ra pi d ly ex h a us t s
fix in g ba t hs so a m a xi m u m o f t we n t y 8 x1 0 p rin ts i s a d vi sa bl e
in e a c h l i t re o f fi xe r .
TES T TO S EE IF F IX E R I S EX H AU S TE D
KODAK FIXER TEST SOLUTION FT1
Wa t e r
Po ta ssi u m io d id e
1 0 0 ml
19 gm
M et h o d:
1 . Hea t wa te r to 3 8 °C .
2 . A dd po ta ssi u m io d i de .
3 . I t is rea d y f o r u se w hen di sso lv e d a n d c oo le d t o 2 0 °C .
U sa ge :
1 . A dd 5 d ro ps o f tes t sol u t ion t o 5 d ro ps of f ixin g ba t h .
2 . A dd 5 d ro ps o f wa te r .
3 . T he fi xe r is ex ha u s te d i f a wh i tis h ye l lo w p re ci pi ta t e fo r ms
i m me dia t el y . Re pla c e f ixe r ba t h .
82
Ibid.p84
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
6 9
WASHING THE PRINT
A r esi d u e of t hi os ul fa te wi ll e ven t ua ll y d ec o m po s e a n d
deg r a d e t he p rin ts a n d wi t h hig h l ev el s , s ul fi din g of t he s ilv e r
i ma ge wi l l o cc u r ov er t i me . 83
Wa s h bef o re h y p o cle a rin g t rea t men t . W a s h t he p r in ts f o r 4
m in u tes , c ha n gin g t he wa t er ba t h a t lea st t wi c e be fo r e t r ea t in g
wi t h a h y po c lea r in g a gen t. T h is wa s h re m ov es a la rg e po r ti on
of t h e fix e r a n d a vo id s ove r lo a d in g t he me c ha n is m of h y po
re m ov a l . 84
THE CLEARING AGENT
T he un p r o te c te d wa te r c ol o u r pa pe r ba se of sa l t ed pa pe r a n d
a lb u m en pr in ts a llo ws a g re a te r a bs o r pt io n of so di u m
t hi os u lfa t e
t ha n
c o m me r cia ll y
p r od u ce d
d eve lo p i n g -o u t
pa pe rs . A c lea r in g a gen t is ess en tia l a s wa te r i s n o t eff ec ti ve
a t re m o vin g e ven l o w l eve ls of so d i u m t h io s ul fa te. A wa sh in g
a id kn o wn a s h yp o cle a rin g a gen t is t h ere fo r e n ec essa r y
A wa s hin g a i d , m o r e co m m on l y kn o w a s h y po clea r in g a g en t ,
con sis t s of 1 % s ol u ti on o f so d i u m s ul p hi t e .
CLEARING AGENT
Wa t e r
So di u m s ul p hi te
1 0 0 0 ml
10 gm
M et h o d:
1 . Hea t wa te r to 3 0 °C .
2 . A dd s o di u m s u l p hi t e.
U se wh en d is so lve d a n d te m pe ra t u re i s a p p rox i ma te l y 2 0 °C .
To U se :
Pla ce p r in ts in ba t h a n d a g it a t e f o r 4 m in ut es . D is ca rd e d a f te r
ma x i m u m of 2 0 8x 1 0 p rin ts . T h e re is a p p rox i ma te l y t h e sa me
ra te of ex ha u s ti on a s s o di u m t hi os u lfa t e f ixe r .
L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v at i o n o f P h o t o g r a p h i c C o l le c t i o n s ,
The Getty Conservation Institute, Los Angeles USA . p220
83
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
7 0
Wa s hin g a l on e wi ll n o t clea r o u t t he so di u m t h io s ul fa te . To
re d u ce t he ri sk of p rin ts de co m p os i n g t he u se o f a h y po
cle a rin g a ge n t is e ssen tia l . I t a s sis t s in t he m o re c o m p le te
re m ov a l of sil ve r - t hi os u lfa t e c o m pl ex es . T he h y po c lea rin g
a gen t r ep la ces t he t hi os u lfa t e ion s wi t h sul fa te i on s wh i c h a re
ea si ly e li m in a te d in t he wa s h .
THE FINAL WASH
In s u ff ic ien t wa s hin g is s ti ll t he ma in c a us e of de te r io ra t io n of
a ll p h o t og ra p hs . Fa c to r s fo r c ri ti ca l wa sh in g :
o
Ag i ta ti on .
o
Wa t e r r ep la ce men t d u rin g t h e wa s h .
o
Wa t e r ha r dn ess .
o
Te m pe ra t u re a bo ve 2 0 °C .
o
Ti me i t ta ke s f o r t h e fi xe r to d if f use o u t of t he pa p er
in t o t he wa te r . 85
So di u m t hi os u lfa te is h ea v ie r t ha n wa te r . I t sin k s a n d n ee d s to
be re m ov ed . W a s he r s wi t h a t o p ove r fl o w wi ll n ot be
su ff ic ien t , 86 t h e ref o r e a g i ta ti on is re q u i r ed .
Be pe da n t ic a b o u t wa s hin g yo u r ha n ds t h o ro u g hl y .
con ta m in a te d wi t h c he m i ca l res i d ue s ta i n p rin ts .
H a n ds
De pen d in g o n t he t hi c kn e ss o f t h e p a pe r , t h e p r in ts s h o ul d
re ce ive a t lea s t a 3 0 - m in u te wa s h . H ea vi e r p a p e rs a n d m o re
den s el y coa t ed pa pe rs s uc h a s a lb u men wi ll re q u i re l on ge r
wa s h t i mes t ha n pla in sa l te d p rin ts .
Con s ta n t r un n in g w a te r is n o t n e ces sa r y t o a c hi eve a n a r c h iva l
wa s h. Con se r ve wa te r a n d en e rg y b y u s in g a t wo t ra y s ys te m
of wa s h in g . Pla ce a ma x i m u m o f 6 p r in t s in a t ra y o f wa r m
wa t er 1 5° C to 1 8°C . T he t ra y n ee ds t o be a t l ea s t do u b le t he
si ze o f t he p r in ts . Ag i ta te t he t ra y fo r 5 m in u te s . Ge n tl y
sh u ff l e t h e p r in ts s o ea c h ha s mo ve m e n t o f wa t e r a c r oss t he
su r fa ce . D ra in ea c h p ri n t a n d pla ce o n e b y on e in t h e c lea n
t ra y o f wa t e r. Ag i ta te a n d s h uf fle a ga i n fo r 5 m in u tes . Re pea t
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 8 9
84
L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v at i o n o f P h o t o g r a p h i c C o l le c t i o n s ,
The Getty Conservation Institute, Los Angeles USA. p220
85
E p h r a u m s , E . ( 1 9 9 5 ) C r e a t i v e E l e m e n t s , 2 1 s t C e n t u r y P u b l i s h i n g L t d , L o n d o n G r e at
Britain.p145
86
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
7 1
t hi s p r o cess fo r a t lea s t 6 to 1 2 c h a n g es of wa t e r. 87 Af te r t he
fi rs t t wo c ha n ges t h e wa te r ca n be use d sa fel y in t he g a r d e n .
If i ma ge s a re t es t p r in t s a 5 m in u te wa s h i s a de q ua te .
TES TS FO R R ES I DU A L SO D IU M TH IO SU L F AT E
KODAK HYPO TEST SOLUTION HT1A
D is ti lle d wa te r
Po ta ssi u m pe r m a n g a n a te
So di u m h y d ro xi de
D is ti lle d wa te r t o m a ke
1 8 0 ml
0.3 gm
0.6 gm
2 5 0 ml
M et h o d:
1.
2.
3.
4.
Hea t 1 8 0 m l wa te r t o 2 0 °C .
A dd po ta ssi u m pe r ma n ga n a te , d iss ol ve .
A dd t he S o di u m h y d r oxi de .
A dd wa t e r t o m a ke 2 5 0 ml .
T o U se :
1 . D il u te 1 ml o f t he s ol u ti on in 1 2 5 ml of wa te r .
2 . Po u r 1 5 ml of t he pr epa re d s ol u t ion in t o a g la s s c on ta in e r.
3 . Ta ke t h e p r in t f ro m t he wa s h t ra y .
4 . Al lo w t o d r ip f o r 3 0 se c on d s in to t he s o lu t ion .
T he res i d ua l fix e r wil l c h a n ge t h e sol u t ion f ro m p u r pl e t o
o ra n ge in 3 0 se co n ds . I t b ec o me s c ol o u rle ss a ga in in on e
m in u te .
T he f oll o wi n g f o r m u la t es ts i f t h e wa s h in g p ro ce d u r e is
a de q ua te l y re m ov in g t h e s od i u m t hi os ul fa te . If t h e re i s m o re
t ha n 0 . 0 0 9g / m 2 , b r o wn s ta in in g wi ll oc c u r . T h e t hi os u lfa te a n d
t he de co m p os it io n by - p ro d u c ts p r o d u ce si lv e r s ul p h id e ,
fo r me d by t he rea c ti on wi t h t he si lv e r n it ra te . 88 The i n t en s it y
of t he s ta i n in di ca te s t he a m o un t of re si d ua l fixe r in t h e p r i n t .
87
A d a m s , A . ( 1 9 9 4 ) T h e P r i n t , L i t t l e , B r o w n a n d C o m p a n y , T o r o n t o C a n ad a . p 1 3 5
L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v at i o n o f P h o t o g r a p h i c C o l le c t i o n s ,
The Getty Conservation Instit ute, Los Angeles USA.p224
88
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
7 2
KODAK HYPO TEST HT-2
D is ti lle d wa te r
2 8 % a ce t i c a c id
Sil ve r n i t ra t e
D is ti lle d wa te r t o m a ke
7 5 0 ml
1 2 5 ml
7.5 gm
1 0 0 0 ml
M et h o d:
1.
2.
3.
4.
Hea t t he 7 5 0 m l wa t er to 2 0 °C .
A dd 2 8 % a ce t i c a c id .
A dd t he S il ve r n i t ra te .
A dd wa t e r t o m a ke 1 0 0 0 ml .
T o U se :
T his me t h o d te s ts t he wh o le p rin t a n d is ti m e con s u min g , b u t
in d i ca te s t he wa s hi n g t i me re q u i re d. M a ke 6 s ma l l p r in ts a n d on
t he ba ck of ea c h wr i te :
a)
b)
c)
d)
e)
f)
1 5 min s wa s h
2 0 min s wa s h
3 0 min s wa s h
4 0 min s wa s h
6 0 min s wa s h
Ref e ren ce p r in t (n o t to be tes te d in t he a bo ve s ol u t ion )
1 . P ro ce ss n o r ma ll y , i n cl u d in g t he h yp o c lea r.
2 . U se t h e 2 t ra y wa s h sy st e m .
3. Agitating and changing water each 5 minutes for the first 15
minutes.
4 . A t 1 5 m in u tes of wa sh t a ke o ut t he p rin t ma r ke d 1 5 m in .
5 . In s u b d ue d li g h t p la ce d in t he si lv e r n i t ra te s ol u t ion .
6 . Ag i ta te f or 4 m in u te s.
7 . Re m ove a n d pla ce i n a t ra y o f 5 % s o d iu m c h lo r i de , a gi ta t e
fo r 4 m in u te s .
8 . Ch ec k f o r s ta i n s . ( T o ke ep s a m ple s , re fi x a n d wa s h . ) 89
9 . Con tin u e t h is p ro ce d u re wi t h a ll t he te st p rin t s EX CE PT t h e
re fe ren ce p ri n t , wa sh in g , a gi ta tin g a n d c ha n g in g wa t e r u p to
t he ti m e m a r ke d on t he ba ck of t he p rin t .
Wh en t h e p r in t s h o ws n o s ign o f s ta i n in g i t t he r ef o re h a s no
so di u m t h io s ul fa te p res en t t h us i n d i ca tin g yo u r id ea l wa s h
ti m e. A ll o w a f u r t he r 1 0 min s of wa sh ti me to e n s u re y o u r
p rin t s wi l l en d u re t he te st of ti m e.
89
A d a m s , A . ( 1 9 9 4 ) T h e P r i n t , L i t t l e , B r o w n a n d C o m p a n y , T o r o n t o C a n ad a . p 2 0 3
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
7 3
M a ke s u r e ha n d s a r e s c r u p ul o us l y cl ea n b ef o re re m ov in g t he
p rin t f r o m t he f in a l wa s h . D r yin g ra c k o r pe gs f o r h a n gi n g
m u st be f r ee f r o m c on ta min a t ion . S ta in s a t t he l a s t st a ge o f
t he p ro ce ss ca n be de va s ta ti n g . T he wo r k , t i me a n d c os ts
in v ol ve d a r e a ll wa s te d , es pe cia ll y i f t h e p rin t ha s been go l d
o r pl a tin u m ton e d.
DRYING
1 . Ai r d ry b y ha n g in g wi t h pe gs on a d r yi n g lin e in a
p ro t ec te d en vi r on m en t .
2 . Pla ce on d r yin g ra c k s fa ce - u p a f te r a l lo wi n g t he p rin ts
to d ri p o ve r t he da r k ro o m s in k.
3 . Hea t d r y us in g a ha i r d r y e r.
T he p rin t wi ll c ha n ge co lo u r a s i t d r ie s , be c o min g co ole r a n d
da r ke r . T he sil ve r p a r ti c les a re a bs o r bi n g m o re vis i ble l ig h t a s
t he y pa c k cl ose r t og et he r .
T he Sa l t p ri n t M a n u a l | P ro ce ssi n g t he p rin t
7 4
10.
S T O R AG E
AND
F R A MI NG
C HAPTER
10
T he s ma ll pa r ti cl e s of s il ve r in p r i n ti n g - o u t pa p e rs c rea t e
gr ea t d et a il b u t i t is t hei r ve r y min us c ule si ze wh i c h ma kes
t he m v uln e r a b le . I ma ge d eg ra da ti on by va ri o us c he m ica l
co m p o un ds in t he a t m os p he re o r i n a d eq ua te p ro ce ssin g ma y
ca use oxi da t ion . T hi s ca n a p pea r a s fa d in g , s ta in in g a n d
di sc ol o u ra ti on . 90
U sin g
c o r re c t
p r o c essin g
me t h od s
of
con se rv a t io n s to ra ge , f ra min g me t ho ds a n d ma te r ia ls wi l l
a ssi st in p ro te c ti n g t he sa l t a n d a lb u men p rin ts f o r m a n y
yea r s.
S TO R A G E
U n f ra me d i ma g es t ha t re q ui re l on g t er m s t o ra ge s h o ul d be
pla ce d i n a r c h iva l m u se u m box es to be ke p t c o ol , da r k a n d
d r y. So la n de r box es a re p ro d u ce d spe c ifi ca ll y f o r t hi s
p u r pos e . H u m i di t y con t r ol i s t he mo s t i mp o r ta n t fa c to r in t he
st o ra g e a r ea . Re si d u a l c he m i ca l s in t he pa pe r a n d e m ul si on a re
a ffe c te d b y hi g h mo is t u re c on ten t en c o u ra gin g m o ul d g r o wt h . 91
Hig h te m pe ra t u re s in c re a se t he r ea c ti on o f t he c he m ica l s of
t he p r in t. A ri ses i n t e m pe ra t u re of 1 0° C ca n d o u ble t h e ra t e
of c h e mi ca l r ea c t io n .
Po l yp r o p ylen e a n d M yl a r™ a re c o m ple t el y in e r t a n d o ffe r
p ro t ec t ion f or ha n dl in g a n d s to r a ge of n ega t iv es a n d
p rin t s .
Con s e rva t ion boa r d s p ro m o te t he l on g e vi t y o f t he p rin t , a s do
t he f ol lo win g m e t ho ds a n d m a te ria ls us ed to con ta in a n d h ol d
t he p rin t .
1 . 1 0 0 % c o t ton ra g m a t t is t he p u re s t fo r m o f c el l ul ose . 92
En s u re t he re a r e n o c he m i ca l i m p u ri t ies in t he
m o un tin g ma te ria ls . M y la r c o rn e rs h o ld t he i m a ge in
pla ce , a l lo wi n g p rin t re m ov a l wi t h o u t d a ma ge .
L a v e d r i n e , B . ( 2 0 0 3 ) A G u i d e t o t h e P r e v e n t at i v e C o n s e r v at i o n o f P h o t o g r a p h i c C o l le c t i o n s ,
The Getty Conservation Institute, Los Angeles USA. p6
90
Ke e f e , L a u r e n c e E . I n c h , D e n n i s 1 9 9 0 , T h e L i fe o f a P h o t o g r a ph , A r c h i v a l P r o c e s s i n g
Matting Framing Storage, 2nd edition Focal Press, USA. p 247
91
92
L a m b , A . R . ( 1 9 9 9 ) F r a m i n g P h o t o g r ap h y , C o l u m b a P u b l i s h i n g , O h i o , U S A . p 5 1
T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g
7 5
2 . Hin ge d m a t bo a rd s c a n b e o pen e d f o r re m ov a l o f p r in t
a n d to in sp ec t fo r da ma g e s uc h a s f a din g, in se c ts o r
m o ul d .
3 . M a t ts s e pa ra te t he p rin t f r o m t he g la ss in t he f ra m e.
4 . T he s ta n da r d is a ti on of m a t si ze s a l lo ws ea s ie r s t o ra g e
un de r con t r ol le d c o n di t ion s. 93
5 . T he s ign a t u re o f t he a r t is t / p ho t og ra p he r m u s t be on
t he p r in t, n o t t he m a t bo a r d . T his ca n b e on t he re ve r se
of t he p r in t , e n s u r e it i s o u ts i de t h e i ma ge a rea o r on
t he fr on t bel o w t h e i ma ge , us e a so ft pen c il .
T he
in f or m a ti on a bo u t t he p r in t s h o ul d a l so be in cl u de d ,
t he t yp e of p rin t , i. e. sa l t o r a l b u men , ton in g use d a n d
t he da te p ho t og ra p h ed a n d da t e p ri n t ed is a ls o u sef u l.
St o ra ge s ho u l d p r o t ec t p r in t s a n d n ega t ive s f ro m h ig h
h u m id i t y , te m pe r a t u re , ul t ra vi ole t ra di a ti on , in s ec t s, m o ul d
a n d c h e mi ca l a t ta c k f r o m a t mo sp h e re a n d s u r ro u n d in g
ma te r ia l s. C a rp e ts , d ra pes a n d o t he r fa b ri cs s h o ul d be a v oi de d
in st o ra ge a rea s . T h ey a bs o rb m oi st u r e in h ig h h u m id i t y a n d
re lea s e i t in to t he a ir . 94
FRAMING
Wh e t he r f ra m in g f o r ex h ib i ti on o r f o r p er son a l u se , t h e
ma te r ia l s u se d a re c ri t i ca l in de te r m in i n g t he lif e of t he p r in t .
Ca u ses of da ma g e t o p ri n t s a re ef fe c ts of h u mi d i ty , a i r
po ll u t ion , hea t , b io l ogi ca l a t ta c ks a n d l i gh t .
L ig h t da m a ge de pen ds on t h re e fa c to rs :
1 . Il l u mi n a n c e.
2 . T he t i me i t is ex po s ed to l ig h t .
3 . T he s pe c t ra l co m p o si ti on of t he lig h t .
As pe r t he re c ip r o ci t y l a w o f p h o to c he m i ca l a c ti on , da ma ge
ca use d b y l ig h t is r ela te d d i re c tl y t o t he p r o d u ct o f t he
ill u m in a n ce a n d t he t i me of t he e xp os u re o f t he i ma g e t o t he
Ke e f e , L a u r e n c e E . I n c h , D e n n i s 1 9 9 0 , T h e L i fe o f a P h o t o g r a ph , A r c h i v a l P r o c e s s i n g
Matting Framing Storage, 2nd edition Focal Press, USA. p.99
93
94I b i d .
p248
T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g
7 6
lig h t . T his m ea n s i f il l u mi n a n c e i s d o u bl ed , t he t i me wh ic h
da ma ge o c c u rs is ha lve d . 95
As t he wa ve len g t h dec r ea se s t he des t r u c ti ve p o we r o f l ig h t
in c re a ses . T h e r is k da ma ge i s g rea te r in t he b l ue a n d t he
ul t ra vi ol e t reg ion s. T he l eve l o f u l t ra v iol e t is s ma l l co m p a re d
wi t h t he vis i ble reg ion b u t i t i s ex t re me l y de s t r uc t iv e. 96 L ig h t
ra ys s h o r te r t ha n 5 0 0 n a n o me t res p r ov id e en o u g h en e r gy to
seve r o rga n ic bon d s in pa pe r . 97 No c on s er va ti on t r ea t men t ca n
re st o re l ig h t - da ma g ed ma te r ia l .
U V ra dia t ion ca n b e con t r ol le d b y :
1 . Fil t ra t ion wi t h con s er va ti on g la s s o r Pe rs pe x t rea te d t o
bl o ck up t o 9 7 % o f U V . S ta n da r d c le a r gla s s bl oc k s
a bo u t 4 7 % of t he da ma gin g ra y s in 3 0 0- 3 8 0 n m ra n g e.
2 . Re d uc in g t he l ig h t i n ten si t y le ve l
3 . Re d uc e t h e d u ra t ion o f t h e ex pos u r e .
95
Ibid.p12
96
C I B S L i g h t i n g G u i d e M u s e u m s a n d A r t G a l le r i e s , I E S P u b l i c at i o n s , L o n d o n , 1 9 8 8 p 1 3
97
Ibid. p11
T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g
7 7
Ext r e mes c ha n ges i n te m pe r a t u r e o ve r a sh o r t pe ri o d o f ti m e
c rea te con den sa ti o n . In a i r wi t h h u m id i t y h ig he r t ha n 6 0 % ,
gela t in a n d a l b u me n a r e fe r ti le c ul t u r e me di a i dea l fo r f un g a l
gr o wt h . Ha n dl in g p h o tog r a p h i c ma te r i a ls wi t h o ut g lo ves ma y
lea v e fin ge r oi ls deg r a d in g t he s u r fa c e a n d c r ea tin g a n
en vi r on men t fo r f u n g us . 98 If co t t on l in t f r ee g lo ves a re n o t
a va i la ble , wa s h a n d t ho r o ug h ly d r y ha n ds be fo re ha n d lin g
p ho t og ra p hs . Co c k r oa c h es a n d si lv e rf is h a ls o t h r ive on ge l a ti n
a n d a l b u m en s ‟ hig h p ro te in con ten t i n t he p rin t , des t r o yin g
t he i m a ge wh i le ea t i n g t he p ro t ein . 99
D ue to t he pr o te in l a ye r in a lb u m en p ri n ts a n d sa l t p rin ts
wi t h ge la tin bin de r s, n on - b uf fe re d 1 0 0 % c o t ton m u se u m
boa r d a r e s ug ges te d . 100 Pla i n s a l t p rin t s a re be t te r
p ro t ec te d us in g a l ka l in e b uf fe re d b o a r ds d ue to t he i r
su sc ep t i b i li t y to a e r ia l ox i da ti on . 101
T i m e – L i f e 1 9 7 2 C a r i n g f o r P h o t o g r a ph s – D i s p l ay , S t o r a g e an d R e s t o r at i o n , T i m e L i f e
Inc USA. p60
98
T i m e – L i f e 1 9 7 2 C a r i n g f o r P h o t o g r a ph s – D i s p l ay , S t o r a g e an d R e s t o r at i o n , T i m e L i f e
Inc USA. p18
99
100
L a m b , A . R . ( 1 9 9 9 ) F r a m i n g P h o t o g r ap h y , C o l u m b a P u b l i s h i n g , O h i o , U S A . p 2 2
W a r e , M . J . ( 1 9 9 4 ) M e c h a n i s m o f I m ag e D e t e r i o r at i o n i n E ar l y P h o t o g r a ph s - t h e
s e n s i t i v i t y t o L i g h t o f W H F T a l b o t 's h al i de - fi x e d I m ag e s 1 8 3 4 - 1 8 4 4 , S c i e n c e M u s e u m an d
N a t i o n a l M u s e u m o f P h o t o g r a p h y , F i l m & T e l e v i s i o n , B r ad f o r d , L o n d o n . p 5 8
101
T he Sa l t p ri n t M a n u a l | S to ra ge a n d F r a m in g
7 8
11.
C HAPTER
11
P R OB L EMS
Sa l t p rin t in g ca n be q ui t e f r us t ra t in g d u e to i ts in he ren t
sen si t iv i t y t o n u me r us s u b st a n c es . T hi s c rea te s a n u m be r of
exa s pe ra tin g res u l ts in c l u din g d if fe ren t t y pes of st a in in g . T hi s
c ha p te r li s ts s pe ci fi c p r o ble m s a n d of fe rs po ssi b le s ol u ti on s .
PROBLEM
CAUSE
S O L U TI O N S
Sa l t pr in ts
a re f la t a n d
we a k . Yo u
ca n n ot ge t a
bla c k .
Th e n e g a t i v e i s n o t
dense enough to allow
long enough exposures
to convert silver salts to
metallic silver.
Increase the contrast by
using potassium dichromate
in the salt solution. Create a
new negative.
Th e n e g a t i v e d o e s n o t
have enough separation
in the high-lights or
shadows.
Re-shoot or remake negative.
Negative lacks contrast.
Tr y p o t a s s i u m d i c h r o m a t e t o
increase the contrast, or
remake a denser negative.
Humidity.
P a p e r m u s t b e e x p o s e d wi t h i n
2 hours of sensitization. Less
if the relative humidity ( RH)
i s h i g h e r t h a n 60 % .
Sensitized paper left too
long before exposure.
P a p e r m u s t b e e x p o s e d wi t h i n
1 hour of sensitisation if RH
i s h i g h e r t h a n 60 % .
Th e r o d o r b r u s h u s e d
for coating the silver
nitrate solution is
contaminated with salt
solution.
Wash the rod between each
coating of silver. Brush may
need replacement.
Th e n e g a t i v e r e q u i r e s
more density and is not
representing the tonal
range of the scene.
Re-shoot or remake the
negative.
Po o r t on a l
ra n ge
T he Sa l t p ri n t M a n u a l | P ro b le ms
7 9
PROBLEM
CAUSE
S O L U TI O N
Stains
Fixer exhausted.
Replace fixer.
Wet hands on sensitized
print before, during or
after exposure.
To w e l d r y h a n d s , h a n d s
s h o u l d a l w a ys b e d r y w h e n
handing the paper.
Print left too long in the
first water bath, excess
silver nitrate in the
water causes stains.
Keep agitating bath and
change water at least every 2
minutes for the first 5
minutes.
P r i n t n o t wa s h e d l o n g
enough in the first
wash.
Excess silver nitrate still in
t h e p r i n t , f i r s t wa s h m u s t b e
at least 20 minutes in total.
Th e a b s o r p t i o n i n t o t h e
paper is uneven.
Size paper or use gelatin in
the salt solution. Make sure
the paper and the solution
are at the same temperature.
Th e s a l t s o l u t i o n h a s
migrated to the back of
the paper during
coating, drawing the
silver through the back.
C l e a n wo r k i n g s u r f a c e . M a k e
the paper large enough so the
coating solution is not near
the edge.
Tr a y s a r e c o n t a m i n a t e d .
W a s h t r a ys , a n d a l l o c a t e
t r a ys f o r u s e o f c e r t a i n
chemicals.
Print too long in fixer .
Use a timer to ensure correct
fixing time.
Fixer has decomposed
and /or is acetic.
Replace fixer, use sodium
carbonate to make fixer
alkaline.
Sensitized paper kept
too long before
exposing.
Pa pe r m us t be ex po sed
wi t h in 1 ho u r o f
sen si t i sa t ion i f t he RH i s
hi g he r t ha n 6 0% .
Inadequate fixing.
Ensure fixer is fresh,
uncontaminated and fixing
time is adequate.
Yellowing of
the print or
yellow s tains
Dark mottled
stains
T he Sa l t p ri n t M a n u a l | P ro b le ms
8 0
P R OB L EM
C AU S E
S OLU TI O N
Uneven
coating
Th e w h i t e p a t c h e s a r e
caused by an uneven
coating of the silver
nitrate solution.
An incandescent low wattage
lamp with light falling at 45°
across the paper will improve
v i s i b i l i t y wh e n c o a t i n g .
Th e d u l l i m a g e a r e a s
indicates salt has not
reached them and the
silver nitrate only is
reacting with the papers
organic substances.
Improve coating visibility
and ensure full coverage of
the image area.
Black Spots
Silver nitrate
contamination.
Clean all the utensils and
surfaces.
White Spots.
(measles
effect)
Insufficient silver
nitrate solution, the
image making silver
chloride is weak.
Ensure an even coating of
silver nitrate at the correct
percentage is applied.
Sa l t pr in t is
un s ta b le a n d
wi l l n o t la s t .
In a de q ua te ex p os u r e,
to n in g, f ixi n g ,
wa s hin g a n d s t o ra g e
me t h o ds .
Sil ve r n i t ra t e
is da n ge r o us
to u se.
Silver nitrate can cause
permanent eye damage.
It stains the skin and if
absorbed is deposited in
various locations around
the body causing
staining of the blood
vessel walls, gums and
mucous membranes,
k n o w n a s a r g yr i a .
If correctly coated, exposed ,
processed and stored the
print has a proven life span
o f a t l e a s t 1 5 0 ye a r s Th e
National Gallery of Australia
houses some fine examples
printed by Talbot in the early
1 84 0‟ s .
Silver nitrate is dangerous if
mishandled. Always wear
gloves when mixing or using
silver nitrate solutions. Wear
eye protection. The safest
method of applying silver
nitrate solutions is using a
r o d a n d s yr i n g e . S i l v e r
nitrate coating baths are
dangerous.
B ron z in g .
Saturation point, the
p r i n t i s o v e r e x p o s e d . 102
Th e p a r t i c l e s o f r e d u c e d
metallic silver migrate
to the surface forming a
layer on the surface of
the print.
Reduce exposure time,
decrease sodium citrate or
make a denser negative.
R e i l l y , J . M . ( 1 9 8 0 ) T h e A l b u m e n & S a lt e d P a pe r B o o k : T h e H i s t o r y an d pr a c t i c e o f
p h o t o g r a p h i c p r i n t i n g , 1 8 4 0 - 1 8 9 5 . , L i g h t I m p r e s s i o n s C o r p o r at i o n . , R o c h e s t e r , U S A . p 7 3
102
T he Sa l t p ri n t M a n u a l | G lo ssa r y
8 1
G L OS S A RY
Ac ti ni c l i g ht : L i g h t in t he U V , vi ole t a n d b l ue reg ion of t he
spe c t r u m t ha t i s re q ui r ed f o r lig h t -in d u ce d c he m i ca l r ea c t ion s
in p ri n t in g -o u t p ro c esses t o c rea t e a n i ma ge .
Al k al i ne : O p p osi t e of a c i d wi t h a pH gr ea te r t ha n 7 on a p H
sca le .
An hy dr ou s : F re e f r o m wa te r .
Ar r o wr o o t: S ta r c h ma de f ro m t u be r o us r oo t s, i n c l u din g
po ta t oes . I t is a fin e whi t e p o wd e r t ha t is use d f o r si zin g a n d
bin d in g .
Bi nde r: T he s u bs t a n ce t ha t b in d s t oge t he r t wo o r m o re
ma te r ia l s or c h e mi c a ls in a m ix t u re , e . g. gel a t in a n d a l b u men
bin de r s ho ld t h e c h lo r i de , di s pe rs in g t he si lve r c h lo ri d e whi le
a d he r in g i t to t he p a pe r .
Bro nzi ng : T hi s de s c ri be s t he sa t u ra ti o n poi n t of a sa l t p rin t
exp os u re . T he me t a lli c s il ve r pa r ti c le s si t s o cl ose t oge t he r
t he y f o r m a la ye r o n t he s u rf a c e.
Buc kl e B ru s h : A te st t ub e, gl a ss o r p la s ti c t u be wi t h c o t to n
wo o l t wis t ed t ig h tl y in o n e en d.
Ca me ra L uc i da : N o t a c t ua ll y a ca me r a b u t a n o p ti ca l d ra wi n g
a id .
D. ma x is t he ma xi m u m den s i t y r ec o r de d on f il m o r pa pe r .
D. mi n i s t h e m in i m u m den s i t y r ec o r de d on f il m o r pa pe r .
De c a -h yd ra te d : C on ta i n s 1 0 m ol ec u le s of wa te r .
De -i o ni ze d Wa te r : Wa t e r p u r if ie d f r o m a ll in o r ga n i c sa l ts b y
a n io n ex c ha n ge p r oc ess o r r eve r se os m osi s b u t ma y s ti ll ha ve
o rga n ic co m p o un ds .
De l i que sc e n t : A bs o r bs wa te r f r o m t he a i r .
De - mi n e r al i ze d W at e r : Sa me a s dei on i s ed wa te r .
De n si ty : A mea s u r e of li g h t a bs o rb ed o r t ra n s mi t te d in a n a rea
of a n i ma ge . T his c a n be m ea s u re d b y a den s i to m e te r . Den si t y
is a l oga ri t h m i c v a l ue. If on e a rea of a n eg a ti ve t ra n sm i ts
t wi c e a s m uc h l ig h t a s a n o t h e r t he d en si t y d if fe ren ce i s 0. 3
(i .e . t h e lo g of 2 )
T he Sa l t p ri n t M a n u a l | G lo ssa r y
8 2
Den si ty R ang e : T h e d if fe ren ce b et wee n t h e l ig h te s t re co r de d
a rea a n d t he da r k es t r ec o r de d a r ea . In fi l m i t r efe r s to
mea s u rin g t h e t h in n es t pa r t o f t h e n e ga t iv e, t hen me a s u rin g
t he d en se st pa r t o f t h e n e ga ti ve a n d su b t ra c tin g t h is va lu e.
T his wi l l gi ve y o u t he den s i t y ra n ge . Den si t o me te r s a r e us ed
to a c c u ra te ly m ea s u re den s i t y.
Di s ti l l e d wa te r : All i m p u ri t ies a re re m ove d by bo il in g wa t er
a n d re con den sin g t he s t ea m.
Ef fl ore sc e n t : L ose m ois t u r e.
E xo t he r mi c : C rea te hea t wh e n d iss ol vin g .
Fadi ng : D e te ri o ra ti on of t he sa l t p rin t t h ro u g h p oo r fix i n g,
in c o m ple t e wa s h in g o ut of fix e rs a n d a i rb o rn e con t a min a ti on
a t t ri b u te t o fa din g.
Fi xe r: A m m on i u m t hi os u lfa t e a n d so di u m t h io s ul p ha te a re
us ed to re m o ve t he un ex pos ed , t h e ref o re s t il l l ig h t sen s i ti ve
sil ve r sa l ts .
Fog : Non -i m a ge si l ve r t ha t s ho ws a s di sc ol o u ra ti on , us u a ll y
c rea te d b y c on ta mi n a t ion o r ex po s u re on t h e li g h t sen si ti ve
su r fa ce b ef o re b ein g pla ce d un de r a n e ga t iv e f o r p rin t in g .
Gel a ti n : A p r ot ein bin de r c rea te d f ro m a n i ma l h i des , b on es
a n d ti ss ues . I t is a n i mp o r ta n t bin d er in p h o to g ra p hy a n d
si zin g in pa pe r ma k in g . V a r io u s g ra des a re a va i la ble .
L ate n t Im ag e : An in vis i ble i ma g e f o r me d on sen s i tis e d fi l m or
pa pe r b y ex p os u r e to lig h t . T h e e xp os u re c rea tes s ma ll
cl u st e rs o f si lve r a t o ms in s il ve r h a li d e cr y st a ls t ha t a re i m a ge
fo r m in g wi t h c he m i ca l de vel o p men t .
L ati t ude : T h e a c c ep ta bl e ra n ge of a n i ma g e b ef o re
exp os u re a n d un de r -ex po s u re ca u se l os s of de ta i l.
ove r -
L i nt e r s: F i b res u s ed t o ma k e co t t on pa pe r . T hes e a re t h e
sh o r te r f i b res l ef t a ft e r t h e c o t ton ha s gon e t h r o ug h t he
gin n i n g ma c hin e . T he l on g e r fi b re s a r e ma de in t o t h r ea d.
Mea sl e s: Bl o t c h y li gh t m a r ks ca use d b y in s u ff i cien t si l ve r,
a lso use d t o des c r ib e da r k ma r ks ma d e fr o m p oo r o r ex ha u st ed
fix in g ba t h .
M on o- hy dr a te d : Co n ta in s on e m ol ec u le o f wa te r .
M S DS : M a te ria ls S a fe t y Da ta S he e t s . T he se p ro vi d e a f ul l
des c r ip t ion of t h e c he m i ca l s, sa fe ha n d lin g , p r ot ec ti on
re q u ir e d a n d f i rs t - a id t rea t m en t.
T he Sa l t p ri n t M a n u a l | G lo ssa r y
8 3
O xi da ti o n: T he re m ova l o f a n ele c t r o n o r e le c t ron s f r o m a n
a t o m o r a m o le c ule .
Ph o t oc h e mi c al Ac t i on : A c ha n ge ca n on l y be ma de b y li gh t
t ha t is a bs o rb e d. T he a m o un t o f p h ot o c he m ic a l c ha n g e is
p ro p o r ti on a te to t he li g h t in ten si t y m u l ti pl ie d by t i me of
ill u m in a t ion .
Ph o t ol y si s: In t he sa l t p rin t i t is t h e a c ti vi t y c rea te d b y t he
exp os u re to l ig h t t ha t c ha n ge s t he s il ve r c h lo r id e t o m et a lli c
sil ve r .
Pu ri fi e d W at e r : T hi s gen e ra ll y m ea n s wa te r p u r if ie d fo r
h u ma n con s u m p ti o n whi c h s ti ll ma y c on ta in sa l ts a n d o r ga n i c
ma t te r .
Py r o: An o r ga n i c de vel o pe r a g en t f o r p h o to g ra p hi c f i l ms .
O t he r
n a me s
use d
a re
p y r oga ll ol ,
p y ro ga l li c
a c id
or
t ri h y d r ox y ben zen e . It off e rs a n exc e p ti on a l t on a l ra n g e a n d
in c re a se hi g hl ig h t s epa ra t ion . P r y o is t oxi c .
Rag : T hese a re o l d ra g s o r n e w o ff - c u t s of c o t ton fa b r ic t ha t
a re b r o ken do wn to ma ke pa pe r . Ra g t h rea ds o ri gin a ll y c o me
fr o m t he l on ge r s t r on ge r f i b res o f t h e co t ton pla n t , a l t h o ug h
pa pe r is n o t o f ten ma de f r o m t h e ra gs to da y, i t ma ke s a ve r y
st r on g pa pe r .
Rati o : T h e r ela t ion sh i p be t ween t wo q ua n ti t ies . F o r exa m pl e
1 : 3 m ea n s on e pa r t wa t er a n d t h ree pa r ts c he m ica l .
Re duc ti on : T he a d di t ion o f a n el ec t r on o r e le c t ron s f r o m a n
atom
or
a
mo le c ule .
O x id a t io n
and
re d uc t ion
o cc u r
si m ul ta n eo u sl y , a r ed u cin g a g en t i s a s ub s ta n c e wh i c h g ive s
u p ele c t r on s a n d b e co m es ox i di ze d .
Re fl e c ti on: Fo r s mo ot h s u rfa ce s a n g le o f in ci den ce is t he sa me
a s t he a n g le o f re fl ec ti on , wh en li g h t st r i kes t he s u rfa ce t he
lig h t b o un ce s ba c k a t t he sa me a n g le . Fo r o t h e r s u r fa c es t he
lig h t i s r ef le c te d ba c k a t di ff er en t a n gl es. i .e . s ca t te re d .
Re fr ac ti o n: W hen li gh t p a sse s t h o ug h on e m ed i u m t o a n o t he r
a ra y is ben t s h a rp ly a t t he s u r fa ce b et we en t he m . In a p rin t
t hi s a f fe c ts t he a p pea ra n ce of t h e si l ve r wh en t h e g los sie r
a lb u m en ref ra c ts t he lig h t . T h e p r in t a p pea rs da r ke r in t he
sha d o ws a n d l ig h te r in t he hi g hl ig h ts t h a n sa l te d pa pe r p rin ts .
Sa t ur a te d S ol u ti on s: (P o ta s si u m di c h r o ma te is of ten use d in a
sa t u ra t ed so l u ti on ) . Th e c he m i ca l is a d de d to l i q ui d un ti l s o me
is l ef t un di ss ol ve d . I t ca n n o t a bso r b / d iss ol ve a n y m o re of t he
c he m ica l , i t is sa t u r a te d . A hi g he r t e m p era t u r e ma y ca use t hi s
T he Sa l t p ri n t M a n u a l | G lo ssa r y
8 4
to d iss ol ve
p re ci pi t a t e .
it
but
wh en
it
co ol s
a
p ro p o r ti on
of
it
wil l
Sel f - ma s ki ng : T h e t hin n e r a r ea o f t he n e ga ti ve a l lo ws t he
sil ve r c h lo r id e con v er t to me ta l li c si lv e r in t h e p rin t . T hi s n o w
da r ke r s u r fa ce of t he sa l t t h u s f o r ms a “ ma s k ” . T h e ex p o sin g
lig h t is he ld ba c k f r o m rea c hin g t h e un re d u ce d si lv e r c h lo ri de
un de rn e a t h . M e a n w hi le t he r es t o f t he sa l t p r in t con t in ue s t o
exp ose un de r t he m o re d en se pa r ts o f t he n e ga ti ve .
Se n si t o me tr y: T h is seek s t o es ta bl is h a rela t ion s h i p be t we en
exp os u re a n d den s i t y p h o to g ra p hi c ma t er ia l .
Si zi ng : T he s ub s ta n ce a d de d to pa pe r to in c rea s es s u r f a ce
st re n g t h . I t r es is ts t he pen e t ra t ion o f s ol u ti on s in t o t h e fi b res
of t h e pa pe r . Gela t i n a n d s ta r c h a re t h e mos t co m m on t y pe s o f
si zin g .
S tep We dg e : T h is i s ei t he r a t ra n spa r en t fi l m o r pa pe r wi t h
den s i t y in c re men t s of 0. 1 5 o r 0. 3 0 . A we d ge o f 2 1 s te ps wi t h
den s i t y un i ts of . 1 5 s te p in t e rva ls gi v e a to ta l ra n ge of 3 . 0 5
den s i t y un i t s. B y c o un ti n g t he n u m be r of di st in c t s te ps in t he
p rin t a n d m u l ti pl y i n g b y t he . 1 5 den s i t y in te r va l b et ween t h e
st ep s gi ves t he e xp os u re ra n g e in loga r i t h mi c un i t s . To
con ve r t t hi s ra n ge to s to ps , m ul t i pl y t he lo g u n i ts b y 3. 3 . 103
O t he r n a m es : s te p t a bl e t, o pt i ca l we d ge a n d t ra n s m is si on g re y
sca le .
We tti ng A g e n t : A p u ri fi ed de te rg en t us ed in t he f in a l wa s h in g
sta ge of f il m p r oc e ssin g , ca u sin g wa te r t o r un of f e ven l y t h us
re d u cin g r u n ma r k s a n d wa t e r s p ot s.
C t e i n ( 1 9 9 7 ) P o s t E x p o s u r e - A d v an c e T e c h n i q u e s fo r t h e P h o t o g r a ph i c P r i n t e r ,
Butterworth-Heinemann, Woburn MA USA. p35
103
T he Sa l t p ri n t M a n u a l | G lo ssa r y
8 5
A P P E N DIX 1 C H EM IC AL S
S A F E TY N O T E S
TRE A T AL L C HEM IC A L S AS D A NG ERO U S O R PO I SO NO U S
o A L W A Y S a d d a c id t o wa t er , NE V ER wa te r t o a ci d. A l wa ys we a r
eye p ro t ec t ion a n d glo ve s .
o Al wa y s d iss ol ve in t he o rd e r o f t he f o r m u la
o Wa i t un t il on e c he m ica l h a s c o m ple t el y di ss ol ve d be fo re
a d din g t h e n ex t.
o U se a f un n e l to po u r s ol u t ion s in to b ot t les . Rin s e f un n e l
a ft e r u se .
o U se p la s ti c o r gla s s st i r rin g r o ds .
o L a be l a ll c on ta in e r s wi t h c he mi ca ls , d a te mi xe d a n d u sa g e
ra ti o i f r eq u i re d .
o D o n o t s to r e c he m i c a ls in f oo d f r i dge .
Ch e mi ca ls a f fe ct t h e bo d y b y :
o
A bso r p t ion : En te rs t he bo d y t h ro u g h t he s k in a n d in to
t he bl oo d s t rea m . Cu ts o r wo u n ds ea sil y a bso r b
c he m ica ls . W hen m ixin g c h e mi ca l s, us e gl ov es f r o m
c he m ica l s u p pli e rs . Su pe r m a r k e t t y pe glo ves o f ten do
n o t of f e r s t ron g en o ug h p ro t ec t ion .
o
B rea t h in g : A i rb o rn e c he mi ca ls , s uc h a s d us t, ga se s a n d
va p o u rs , c a n en te r t he bo d y t h o u g h t he n o se a n d
m o u t h. I f yo u r wo r k en vi r on men t is n ot wel l v en ti la te d ,
m ix c he mi ca ls o u t d oo rs ( b ree ze b lo wi n g a wa y f r o m yo u
fa c e) . M a ke s u r e yo u ha ve ga s ma s k s t o p r o te c t a ga in s t
c he m ica l f u m es.
o
In g es ti on : D o n o t e a t o r d r in k i n t he a rea wh e re yo u a re
wo r k in g o r mix in g c he m i ca ls . 104
Kee p to ps a n d ca p s ti g h t l y cl ose d a s so me c he m ica ls wi l l
a bs o r b t he m ois t u r e f ro m t h e a i r ( kn o wn a s del iq u es cen t ). T his
wi l l a l t e r t he wei g h t a n d m a y a l lo w a c r us t to fo r m on t he
J a m e s , C . ( 2 0 0 2 ) T h e B o o k o f A lt e r n at i v e P h o t o g r a ph i c P r o c e s s e s , D e l m ar , N e w
York.p344
104
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
8 6
su r fa ce .
O t he r s los e t h ei r m ois t u r e (ef fl o res ce n t ) , h a ve
da n g e ro u s f u mes , o r eva p o ra te . Ea c h t i me y o u b u y c he m i ca l s
c he c k t h ei r M a te r ia l s Sa fe t y Da ta S h ee t fo r c o r re c t s to ra ge a n d
ca re .
Te m pe ra t u re s in mi xin g f o r m ul a s a re i m po r t a n t so f ol lo w t he
in s t r u ct io n s , a s so me :
o
re q u ir e wa r m wa te r te m pe ra t u r e t o d iss ol ve
o
c rea te hea t wh e n d i sso lv in g (k n o wn a s exo t he r m i c)
o
so me a bs o r b he a t ( k n o wn a s en do t h e r mi c)
D iss ol ve c h e mi ca l s in t he o r de r t h e fo r m u la lis t s a n d wa i t
un ti l ea c h c he m i ca l ha s di ss ol ve d be fo r e a d din g t h e n ex t.
MEASURING OUT CHEMICALS:
Ac c u ra te sc a le s a re in d is pen sa ble . Ele c t ron ic
di gi ta l s ca l es a re re la ti vel y in ex pe n siv e. T he
a c c u ra c y a n d ra n g e ca pa c i t y wil l re f lec t in t he
p ri ce . S ca les to m ea su r e 0 . 0 1 of a
gra m wi ll be m o re exp en si ve t ha n
t h ose t ha t mea s u re 0 . 1 0 g m . P la ce a s he et of
pa pe r un de r t he s c a les in ca se o f s pi ll a ge. D o
n o t pl a c e c he m i ca l s di re c tl y on t o t he weig h in g
pla t e of t he s ca le s. Pla ce a s ma ll s he et of pa pe r on t he
we ig h in g p la te fo r mea s u rin g s ma ll e r a m o un ts . F o r mea s u ri n g
la rge r a m o un ts of d r y c h e mi ca ls us e d is po sa b le pa pe r o r
pla s ti c c up s. Re m e m be r t o co m pen sa t e fo r t h e ex t ra m a s s in
t he mea s u re men t s wh e n u sin g a c u p o r pa p e r.
C O N V E R S I O N S O F M E A S U R E M E N TS
o Weig h t s: To con ve r t g ra m s t o o un ce s
Di vi de t he ( g m) g ra m s b y 2 8 . 4 = o un ce s.
o L iq u i d m ea s u re m en t s: M i ll il it r es ( m l ) t o fl ui d o u n c es .
Di vi d e m l b y 2 8 . 4 = i m pe ria l fl u i d o un c e .
o M ea s u re me n t in a r e a :
Cen ti m e t res t o in c hes , c m x 0 . 3 9 3 7 = in c hes .
In c he s t o c en t i me t res , in c he s x 2 . 5 4 0 0 = c m .
Exa m pl e fo r 8 x 1 0 in c hes = 2 0. 3 2 c m x 2 5. 4 c m .
o Te m pe ra t u re : T o c o n ve r t Ce lsi u s t o Fa h ren h ei t
1 . M u l ti pl y t he te m pe r a t u re i n Cel si us b y 9 .
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
8 7
2 . D iv id e a n s we r b y 5 .
3 . A dd 3 2 to t he res u l t .
Exa m ple f o r 2 0° C
1. 20 x 9 = 180
2. 180 ÷ 5 = 36
3. 36 + 32 = 68° F
o Pe r cen ta ge so l u ti on s : Kn o wn a s p e rc en t wei g h t fo r v ol u m e
(% w/ v )
Pe r cen ta ge s ol u t io n s a re u se d wh e n t h e q u a n ti t y of
t he c he m ica l is t o o sm a ll t o wei g h t a c c u ra te l y .
Fo r exa m p le : pe rc en t a ge w e ig h t fo r
sol u t ion is 2 g m in 1 0 0 ml of s ol u t ion .
vo l u me :
2%
P er c e nt a ge vo l u me fo r vo l u me 2 % sol u t ion i s 2 ml in
1 0 0 ml of s ol u t ion .
C H E M I C A L S U S E D I N T H I S M A N U AL
A M M O N I U M C H L O R I D E N H 4 Cl
o
A pp ea ra n ce : W h i te od o u rl ess c r ys ta l s o r p o wd e r .
o
Ha z a rd s : Ha r mf u l if s wa ll o we d ,
re s p i ra to r y s ys t e m a n d s kin .
o
O t he r n a m es : Sa l a m m on ia c , m u ria te o f a m m on ia .
o
S ub s ti t u te : sodium chloride, calcium chloride, potassium
chloride.
o
U ses : Sa l t s ol u t ion i n sa l t a n d a l b u m en p rin t in g .
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
i r ri t a n t
to
t he
e ye s,
A M M O N I U M T H I O C Y A N A T E N H 4 SC N
o
A pp ea ra n ce: W h i te od o u rl ess c r ys ta l s o r p o wd e r
o
Ha z a rd s: Ha r mf u l if s wa ll o we d ,
re sp i ra to r y s ys t e m a n d s kin .
o
O t he r n a m es : A m m o n i u m r h o da te
o
S ub s ti t u te : Nil
o
U ses : To n in g fo r sa l t a n d a l b u men p rin t in g .
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
i r ri t a n t
to
t he
e ye s,
ARROWROOT (STARCH SIZING/BINDER)
o
A pp ea ra n ce: F in e whi t e p o wd e r
o
Uses: Sizing or binder
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
8 8
o
Ava ila b le f r o m: S up er ma r k e ts
C A L C I U M C H L O R I D E C a Cl 2
o
A pp ea ra n ce: W h i te od o u rl ess f la kes o r po wd e r
o
Ha z a rd s: Ha r m f ul i f s wa ll o we d , i r r i ta t in g t o t he e ye s,
re sp i ra to r y s ys t e m a n d s kin .
o
Other names: Calcium(II) chloride.
o
S ub s ti t u te :
Sodium
potassium chloride.
o
Uses: Salt solution in salt printing.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
chloride,
ammonium
chloride,
C A L C I U M C A R B O N A T E Ca C O 3
o
A pp ea ra n ce: W h i te od o u rl ess po wd e r o r l u m ps .
o
Ha z a rd s: E ye , res p i r a t o ry a n d s ki n i r ri ta n t .
o
O t he r n a m es : Li m es t on e , c al ci t e , ar a g on i t e , ch al k .
o
U ses : To n in g .
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
CITRIC ACID C6H8O7
C (O H) C O OH .( C H 2 C O O H) 2
o
A pp ea ra n ce: C ol o u r less , o d o u rle ss c r y sta ls o r g ra n ule s ,
eff lo re sc en t in d r y a i r, d el iq u es cen t i n m oi s t a i r . V e ry
sol u b le in wa te r .
o
Ha z a rd s:
ir r i ta n t .
o
O t he r n a m es : H y d r o g en ci t r at e
o
S ub s ti t u te : S od i u m c i t r at e , cal ci u m ci t r a t e
o
U ses : S to p ba t h
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs o r h ea l t h fo o d s to r es
S ev e re
e ye
i r r i ta n t.
Res pi ra t o ry
and
s kin
GELATIN (BINDER/SIZING)
o
A pp ea ra n ce: L ig h t ye ll o w o r c ol o u rle s s c oa rse p o wd e r ,
fla kes o r s hee t s.
o
Ha z a rd s: Ni l
o
O t he r n a m es : Gela t i n e
o
Uses: Sizing and as binder. Swells and absorbs up to 10
times its weight in water.
o
Ava ila b le f r o m: C h em i ca l s u p pl ie rs a n d s u pe r ma r ke t s ,
n o te: fo o d gela t in ma y ha v e a d d i ti ves .
G L A C I A L A C E T I C A C I D C H 3 CO O H
o
A pp ea ra n ce: C ol o u rl ess p un gen t s m el l . Fre e zes a t 1 6 . 6 ° C
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
8 9
o
Ha z a rd s: C o r ros iv e. I t s va p o u r ca u ses i r ri ta t ion to t he
eye s, a d r y a n d b u r n in g n os e, s o re t h r o a t a n d con ges t ion
to t he l un gs . Fl a m m a bl e.
o
O t he r
n a m es :
Ac et i c
me t ha n e ca rb ox y li c a ci d .
o
Uses: Fermenting albumen solution .
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
a c i d;
et ha n oi c
a ci d,
G O L D C H L O R I D E S O L U T I O N 1% Na A u Cl 4
o
A pp ea ra n ce: Pa l e go ld l i q ui d .
o
Ha z a rd s: C o r ro si ve, des t r u c ti ve of m u co u s m e m b ra n es
so a l wa ys ha n dle wi t h g lo ves a n d go gg l es , di r ec t c on ta c t
sh o ul d be a v oi de d .
o
O t he r
n a m es :
S od i u m
te t ra c hl o r oa u ra te ,
c hl o roa u ra t e a ci d go ld t ri c hl o ri de go ld ( I I I )
t ri h y d ra te .
o
S ub s ti t u te : Hydrogen t e t ra c h lo r oa u ra te ( I I I)
o
Uses: Gold toning.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
so d i u m
c hl o ri de
GLYOXAL C2H2 O2
o
A pp ea ra n ce: C lea r l i q ui d .
o
Ha z a rd s: Ha r m f ul if in ge st e d o r i n ha le d, i r ri ta n t t o s k in
eye s a n d re sp i ra to r y t ra c t. A l wa ys ha n dl e wi t h g lo ves ,
ma sk a n d g og gle s , d ir ec t con ta c t m us t b e a vo id ed .
o
O t he r n a m es :
o
Uses: Hardening gelatin.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
ISOP ROP YL ALCO HOL C3H8O
o
A pp ea ra n ce: C ol o u rl ess l iq u i d, s li g h t o d o u r of a l c o ho l.
o
Ha z a rd s: F la m ma bl e , t ox ic .
o
O t he r n a me s: R u b bin g a l co h ol ,
a lc o ho l .
o
Uses: Hardening albumen coatings.
o
Ava ila b le f r o m: C h e m is ts , c h e mi ca l s up pl ie rs .
is op r opa n ol , p r o p a n o l
M E T O L C 7 H 9 NO
o
A pp ea ra n ce: W h i te t o ye ll o wi s h p o wd e r .
o
Ha z a rd s: Ca u ses s k i n po ison in g . W ea r g lo ves .
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
9 0
o
O t he r n a m es : El on , pi c to l p h o t ol .
o
S ub s ti t u te : Phenidone.
o
Uses: Developing agent for films.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
P O T A S S I U M C H L O R I D E K Cl
o
A pp ea ra n ce: C ol o u rl ess wh i t e p o wd e r o r c r y s ta ls .
o
Ha z a rd s: A ffe c ts ca r dia c m u sc le s . Hi g h d oses ca n c a use
ca r dia c a r res t a n d r a pi d dea t h .
o
O t he r n a m es : C hl o ri de o f p o ta s h , m u ria te o f p o ta s h .
o
S ub s ti t u te : Sodium chloride, ammonium chloride, calcium
chloride.
o
Uses: Salt solution for salt and albumen printing .
o
Ava ila b le f r o m: c he m ica l s u p pli e rs .
P O T A S S I U M C H L O R O P L A T I N I T E 2 0 % K 2 P t Cl 4
o
A pp ea ra n ce: R ed d i s h s ol i d
o
Ha z a rd s: Po is on o u s , c o r ro si ve to h u ma n sk in , ca n ca use
a ll er gi c ef f e c t s , i s a n exp er i m en t al m u t a g en .
o
O t he r n a m es : Potassium tetrachloroplatinate , potassium
Chloroplatinite.
o
S ub s ti t u te . Nil
o
Uses: Toning.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
P O T A S S I U M D I C H R O M A T E K 2 Cr 2 O 7
o
A pp ea ra n ce: B ri g h t re d o ra n ge c ry s ta l s
o
Ha z a rd s: Tox i c if s wa l lo we d o r b y in ha l e d. I r ri ta n t t o
sk in a n d r es pi ra t o r y s ys te m . Ca n ca u s e se ri o us da ma ge
to
e ye s,
ha r m f u l
to
t he
a q ua t ic
en vi r on men t ,
ca r cin ogen i c.
o
O t he r n a me s: Bi c h r o ma te of po ta s h , Bi c h r o ma te o f
po ta ssa , p o ta s si u m bi c h r o ma te , r ed c h r o ma te o f p o ta s h .
o
S ub s ti t u te : Ammonium dichromate.
o
Uses: increases contrast in salt & albumen printing.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
POTASSIUM IODIDE KI
o
A pp ea ra n ce: W h i te c r ys ta ls , p o wd e r o r g ra n u les .
o
Ha z a rd s: M il d i r ri ta n t . A ffe c ts t h y ro i d.
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
9 1
o
O t he r n a m es : I o din e o f p o ta s h .
o
S ub s ti t u te : Sodium iodide.
o
Uses: Test for residual fixer.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
P O T A S S I U M P E R M A N G A N A T E K Mn O 4
o
A pp ea ra n ce:
lu s t re .
P u r pl e
/b la c k
c ry s ta l s
wi t h
a
m e ta l li c
o
Ha z a rd s: Po we rf u l o xid is in g a g en t .
o
O t he r n a m es : Pe r ma n ga n a te o f p o ta s h . Con d y‟ s c r ys ta ls
o
S ub s ti t u te : Sodium permanganate.
o
Uses: Test for residual fixer.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
P Y R O G A L L I C A C I D C 6 H 3 (O H) 3
o
A pp ea ra n ce: W h i te po wd e ry c r ys ta ls .
o
Ha z a rd s: P oi son o u s , t oxi c if
in ha l e d , wea r ma s k a n d g lo ves .
o
O t he r n a m es : P y ro , P y ro ga l lo l , t ri h y d r o xben zen e .
o
Uses: Active agent in processing negatives .
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
s wa l lo we d ,
t o uc h ed
or
S I L V E R N I T R A T E Ag N O 3
o
A pp ea ra n ce: C ol o u rl ess f la t c r ys ta ls .
o
Ha z a rd s: O xi di zi n g a gen t . Wea r e ye p ro t ec t ion , g lo ves
a n d ma s ks . Ca n ca u se pe r ma n en t da m a ge to e yes , b u rn s
on con ta c t t o e ye s o r s k in , a n d is h a r m f ul t o a q ua t ic
en vi r on men t .
o
O t he r n a m es : N i t ra t e of si lv e r, l u n a r ca us t ic .
o
Uses: Sensitising salted paper, albumen and numerous other
alternative processes.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M A C E T A T E CH 3 C O ON a . 3H 2 0
o
A pp ea ra n ce:
c r ys ta l s
C ol o u rl ess ,
t ra n s pa re n t
ef fl o res cen t
o
Ha z a rd s: Ir r i t an t , ke ep co ol in ti g h tl y se a le d b o t tle .
o
O t he r n a m es : A ce ta t e of s oda , s o di u m e t ha n oa te .
o
Uses: Lower acidity in toning.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
9 2
S O D I U M B I S U L F I T E N aH S O 3
o
A pp ea ra n ce: W h i te c r ys ta ll in e p o wd e r
o
Ha z a rd s: Ha r mf u l if s wa ll o we d o r i n ha l ed .
o
O t he r n a m es : A ci d s ul fi t e of s o da
o
S ub s ti t u te : Sodium metabisulfite.
o
Uses: Pyro developer.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M C A R B O N A T E Na 2 C O 3 a n d N a 2 C O 3 .H 2 0 a n d N a 2 CO 3 .1 0H 2 0
o
A pp ea ra n ce: W hi t e o r co lo u r les s po wd e r , g ra n ule s o r
c r ys ta l s .
o
Ha z a rd s: E ye , s ki n a n d res pi ra t o r y i r ri ta n t .
o
O t he r n a mes : So da , wa s h in g so da , ca r bon a t e o f s o da ,
so da a s h .
o
S ub s ti t u te : Potassium carbonate.
o
Uses: Reducing acidic conditions in the fixer.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M C H L O R I D E Na C l
o
A pp ea ra n ce: W h i te po wd e r o r c ol o u rl es s c r ys ta l s .
o
Ha z a rd s: Ca n ca us e eye s k in a n d re s pi ra to r y i r r i ta ti on .
o
O t he r n a m es : Ta ble sa l t, co m m on sa l t .
o
S ub s ti t u te : Potassium chloride.
o
Uses: Salt solution for salt and albumen prints.
o
Ava ila b le f r o m: He a lt h fo o d s to re s ( c he c k t he re a re n o
a d di t ive s) , c h e mi ca l s u p pl ie rs .
S O D I U M C H L O R O P A L L A D I T E Na 2 Pd Cl 4
o
A pp ea ra n ce: Re d b r o wn c r ys ta ll in e po wde r o r c r ys ta l s .
o
Ha z a rd s: Po is on o u s, Do n o t in ge s t , b rea t he d us t o r m is t .
D o n o t ge t in e y es , on s kin o r cl o t hin g.
o
O t he r n a m es : S o di u m c hl o ro pa l la da te (I I ); co d i u m
te t ra c hl o r opa lla d i u m (I I ) ; so d i u m c h lo r opa lla d i te ( I I ) .
o
Uses: Toning.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M C I T R A T E Na 3 C 6 H 5 O 7
o
A pp ea ra n ce: F in e w hi t e o do u r les s c r ys t a ls .
o
Ha z a rd s: Ir r i t an t t o ey es s k i n an d r e s p i r at or y s y s t em .
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
9 3
o
O t he r n a m es : Tr i s od i u m ci t r a t e .
o
S ub s ti t u te : C al c i u m ci t r at e, ci t r i c a ci d .
o
Uses: In salt prints to decrease contrast increases light
sensitivity.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M H Y D R O X I D E Na OH
o
A pp ea ra n ce: W h i te de li q ues cen t l u m p s , fla ke s, bea ds o r
st ic k s .
o
Ha z a rd s: Hi g hl y to x ic , c a us ti c , wi ll ex p lo de in h o t wa te r ,
va p o u r is da n ge r o us , wea r fa ce ma s k gl ov es a n d e ye
p ro t ec t ion . In ge s ti o n ca n be fa ta l .
o
O t he r n a m es : C au s t i c al k al i , c au s t i c s od a .
o
S ub s ti t u te : P o ta s si u m h y d rox i de.
o
o
Uses: Test for remaining fixer in print.
Ava ila b le f ro m : C h em i ca l s u p pl ie rs a n d s u pe r ma r ke t s
(„ D r a in o ‟ f o r c lea r in g bl o c ke d d ra in s ) .
S O D I U M M E T A B O R A T E N aB O 3 .4 H 2 0
o
A pp ea ra n ce: W h i te c r ys ta ls .
o
Ha z a rd s: M o de ra te ha za r d on in ges t io n a n d in ha la ti on ,
sli g h tl y tox i c on s ki n .
o
O t he r n a m es : K o da k ba la n ce d A l ka l i, K o da l k
o
S ub s ti t u te : Bo ra x, s od i u m te t ra bo ra t e
o
Uses: Film developer.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M S U L P H I T E Na 2 S O 3
o
A pp ea ra n ce: W h i te c r ys ta ls o r po wd e r .
o
Ha z a rd s: Po ssi b le m u ta g en . Ha r mf ul b y in ha la ti on ,
in ge st io n a n d s k in c on ta c t . Ey e s k in a n d res pi ra t o r y
ir r i ta n t . P r ol on g ed o r re pea te d e xp os u re ca n ca us e
a lle r gi c rea c ti on s . M ixe d a ci d re lea s e s s ul p h u r di ox id e
ga s .
o
O t he r n a m es : S ul p h i te , s ul p h i te o f so da .
o
S ub s ti t u te : Sodium bisulphite.
o
Uses: Hypo clearing bath assists removal of the fixer from
the paper.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
S O D I U M T E T R A B O R A T E ( B O R A X ) Na 2 B 4 O 7
T he Sa l t p ri n t M a n u a l | A pp en dix 1 C he m ica ls
9 4
o
A pp ea ra n ce: W h i te c r ys ta ll in e p o wd e r .
o
Ha z a rd s: L o w ha za r d ris k b u t ca n be t oxi c i f si gn i fi ca n t
a m o un ts a r e i n ha l ed , i n ge st e d o r m a ke c on ta c t wi t h
sk in .
o
O t he r n a mes : Bo r a x, bo ra t e o f s o da o r so d i u m,
te t ra b o ra te so d i u m bo ra t e , or di so d i u m te t ra bo ra t e .
o
S ub s ti t u te : n on e .
o
Uses: gold toning to render acidic gold chloride alkaline
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs , s u pe r ma r ke ts .
S O D I U M T H I O C Y A N A T E Na S C N
o
A pp ea ra n ce: C ol o u rl ess o r wh i t e de li q ue scen t c r ys ta l s .
o
Ha z a rd s: Ha r m f ul b y in ha la ti on , in g es ti on a n d s kin
con ta c t . Con ta c t wi t h a ci d li be r a t es hi g hl y t oxi c ga s.
o
O t he r n a m es : S od i u m r h od an at e an d s od iu m s ul fo c ya n i de .
o
S ub s ti t u te : Potassium thiocyanate.
o
Uses: Toning.
o
Ava ila b le f r o m: C h e m ica l s u p pli e r .
S O D I U M T H I O S U L F A T E Na 2 S 2 O 3 . 5H 2 0
o
A pp ea ra n ce: L a r ge t ra n s pa r en t c r ys ta ls , wh i t e p o wd e r .
o
Ha z a rd s: Ey e i r ri ta n t , ca n de c o m po se
su l p h u r d iox i de ga s .
o
O t he r n a m es : H y po , s od i u m h yp os u lf i te .
o
S ub s ti t u te : Ammonium thiosulfate.
o
Uses: Known as fixer „hypo‟: dissolves the unexposed silver
chloride, removing the light sensitivity of the salt print.
o
Ava ila b le f r o m: C h e m ica l s u p pli e rs .
re lea s in g
T he Sa l t p ri n t M a n u a l |
t oxi c
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A P P E N D I X 2 M A T ER I AL
S U P P L I ER S
C H E M I C A L S A N D A L TE R N A TI V E P R O C E S S K I T S
BOSTICK & SULLIVAN.
P. O . Box 1 6 6 3 9 , Sa n ta Fe , 8 7 5 9 2, Ne w M exi co U SA
Tel : 5 0 5 4 7 4 0 8 9 0 Web : www. b o s ti c k - s ul li va n . co m
G O L D S TR E E T S TU D I O S
7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia .
Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : www. g o ld s t ree ts t u di o .c o m .a u
PHOTOGRAPHER‟S FORMULARY INC
P. O . Box 9 5 0 C on do n M o n t a n a 5 9 8 2 6 U S A.
Web : w w w. p h o t of o r m u la r y. c o m
VANBAR
5 3- 5 7 M un s te r T ce No r t h M el bo u rn e V i c to r ia 3 0 5 1 A us t ra li a .
Tel 6 1 3 9 9 1 5 1 9 0 0 Web : www. v a n ba r. c o m.a u
EXPOSURE FRAMES:
G O L D S TR E E T S TU D I O S
7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia .
Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : www. g o ld s t ree ts t u di o .c o m .a u
SHEET FILM:
FORMA - BLANO NEGRO. AUSTRALIA.
ww w. b l a n con e g ro . c o m.a u
ILFORD - PHOTO RESOURCES. AUSTRALIA.
ww w. p h o t o re so u r ce s. co m .a u
GLASS ROD CHEMICAL SPREADERS:
G O L D S TR E E T S TU D I O S
7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia .
Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : www. g o ld s t ree ts t u di o .c o m .a u
P AP E R S U P P L I E R S :
G O L D S TR E E T S TU D I O S
T he Sa l t p ri n t M a n u a l | A pp en dix 2 M a t er ia l s u p pl ie rs
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7 0 0 J a me s L a n e T re n t ha m Ea s t V i c to r ia 3 4 5 8 A us t ra l ia .
Tel : 6 1 3 5 4 2 4 1 8 3 5 Web : www. g o ld s t ree ts t u di o .c o m .a u
NEIL‟S ART SUPPLIES/ NEIL WALLACE PRINTMAKING SUPPLIES
4 4- 4 6 G ree ves S t r ee t , Fi t z ro y V i c t o ria A us t ra lia 3 0 6 5
Tel : 6 1 3 9 4 1 9 - 5 9 4 9 We b : www. e - a rt s to r e. co m .a u
BOSTICK & SULLIVAN.
P. O . Box 1 6 6 3 9 , Sa n ta Fe , 8 7 5 9 2, Ne w M exi co U SA
Tel : 5 0 5 4 7 4 0 8 9 0 Web : w ww. b o s ti c k - s ul li va n . co m
S TE P W E D G E S
S T O U F F E R I N D U S T R I E S w w w. s t o u ffe r .n e t
T he Sa l t p ri n t M a n u a l | A pp en dix 2 M a t er ia l s u p pl ie rs
9 7
B IB L I OG RA P H Y
A da ms , A . ( 1 9 9 4 ) T h e P r i n t, L i t t le , B r o wn a n d Co m pa n y ,
To r on to Ca n a da .
Cra wf o rd , W . ( 1 9 7 9 ) K ee p ers o f th e L ig h t , M o rga n & M o r ga n ,
In c. , Ne w Yo r k , U S A .
Ct ein ( 1 9 9 7 ) P o s t E x po s ur e - A d v a n ce Te c h n iq ues fo r t he
P ho to g r a p h i c P r i n te r, B u t te r wo r t h - Hein ema n n , W o b u rn
MA USA.
E.J .Wa l l a n d F. I .J o r d a n ( 1 9 7 5) P ho to gr a p h i c F a c ts a n d
Fo r m u l as , A m e ri ca n P h o t og r a pi c B o ok P u bl is h in g C o. ,
In c. , Ne w Yo r k U SA .
Ede r , J . M . ( 1 9 7 8 ) H i s to r y o f P ho to g r a ph y, D ov e r P u bl ic a ti on s
In c N e w Yo r k .
Ep h ra u m s, E . ( 1 9 9 5 ) Cr e a ti v e E l e me n ts , 2 1s t C en t u r y
P u bli s hin g L t d , L on don G r ea t B r i ta in .
Fa r be r , R . ( 1 9 9 8 ) H i s to r i c P ho to g r a p h ic Pro c es s es : A G u i d e t o
Cr e a t i ng H a n d m a d e Pho to g r a p h i c I m a ge s , A ll wo r t h P re ss ,
Ne w Yo r k .
Gra y , M . , O l l ma n , A . a n d M c C us ke r , C. ( 2 0 0 2 ) Th e Fi rs t
P ho to g r a p hs W i ll i a m H e nr y Fo x T a l bo t a n d th e B ir t h o f
P ho to g r a p h y, Po we r Ho us e B oo k s U S A, N e w Yo r k .
H un t, R. ( 1 9 7 3) A M a n u a l o f P ho to gr a p h y, A rn o P res s In c . U SA .
H u tc h in g s, G . ( 1 9 9 2 ) T h e Bo o k o f P yro , Bi t te r D og P ress ,
Gra n i te Ba y, C A .
J a me s, C. ( 2 0 0 2) T h e Bo o k o f A l t er n a t i v e P ho to gr a p h i c
P ro ces s es , De l ma r , Ne w Yo r k .
Ken n e t h-M e es , C. E . a n d J a mes , T . H . ( 1 9 6 6 ) T h e T heo ry o f t h e
P ho to g r a p h i c P ro ces s , T he M a c mi lla n C o mp a n y, Ne w
Yo r k .
L a m b , A . R . ( 1 9 9 9 ) F r a mi n g P ho to gr a p h y , Co l u m ba P u b lis h in g,
O h io , U S A.
L a ve d rin e , B. ( 2 0 0 3) A G u i de to t he Pr e v en t a t i ve Co ns e r v a ti o n
o f P ho to g r a p hi c Co l l ec t io ns , T he G e t ty C on se r va ti on
In s t i t u te , L os An ge l es U S A.
Ne ls on , M . I . ( 2 0 0 4 ) P re c is io n D i gi t a l N e ga t i ves : Fo r Si l ve r &
O th er A l t er n a t i ve Pr o ces s es , M a rk I Nel s on .
Rei ll y , J . M . ( 1 9 8 0 ) T he A l b u m e n & S a l te d P a pe r Bo o k : T he
His to r y a n d pr a c t i c e o f p ho to gr a p h i c pr i n t i ng , 1 8 4 0 1 8 9 5 ., L ig h t I m p res sion s Co r p o ra ti on . , Ro c hes t e r, U SA .
T he Sa l t p ri n t M a n u a l | Bi b li og ra p h y
9 8
Sc ha a f , L . J . ( 1 9 9 6 ) R eco r ds o f t h e D aw n o f Ph o t o gr a p h y
T a l bo t' s No te bo o ks P & Q , U n i ve rs it y P re ss Ca m b ri dg e,
Ca mb r i dge G r ea t B r i ta i n .
Sc ha a f , L . J . ( 2 0 0 0 ) T he P ho to gr a p h i c Ar t o f Wi l l i a m H e nr y F o x
T a l bo t , P ri n c et on U n ive r si t y P r ess , O xf o rd s hi re , U K.
St r oe be l, L ., Co m p t on , J ., C u r r en t, I . a n d Z a kia , R . ( 1 9 8 6 )
P ho to g r a p h i c M a t er i a ls an d P ro ces s es , B u t te r wo r t h
P u bli s he rs , S t on e ha m , M A , U S A .
T u rn e r , S. ( 1 9 9 8 ) T h e Bo o k o f F i ne P a p er s , T ha me s a n d H u ds on
In c, Ne w Yo r k .
Wa ll , E . J . a n d J o r da n , F. I . ( 1 9 7 5 ) P ho to gr a p h ic F a c ts a n d
Fo r m u l as , A m e ri ca n P h o t og ra p hi c Bo o k P u bli s hin g Co . ,
In c. , Ne w Yo r k U SA .
Wa ll s, H. J . a n d A t t r id ge , G. G . ( 1 9 7 7 ) B as i c P ho to S c ie n c e, ho w
p ho to g r a p hy w o r ks , Fo ca l P ress , L on d on .
Wa r e, M . ( 2 0 0 6 ) T he C hr ys o ty p e M a n u a l, T h e C ro m we l l P re ss
L t d, U K .
Wa r e, M . J . ( 1 9 9 4) M ec h a n is m o f I m a ge D e te rio r a t io n i n E ar l y
P ho to g r a p hs - t he s e ns i ti v i t y to Li g h t o f WH F T a l bo t' s
h a l i de -f i xe d I m a ges 1 8 3 4 - 1 8 4 4 , S ci en ce M use u m a n d
Na ti on a l M u se u m o f P h o t og ra p h y, F il m & Te le vis ion ,
B ra df o rd , L on d on .
Wa r e, M . J . ( 2 0 0 6. ) Go l d i n Ph o t o gr a p h y ., f fo t of fi l m p u b lis h in g ,
B ri g h ton , U K.
T he Sa l t p ri n t M a n u a l | Bi b li og ra p h y
9 9