History of Photography in Astronomy

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History of Photography
Astronomical Photography
Mary Kay Hemenway
With materials from
McCormick Observatory
and other sources
Niépce and Daguerre
• In 1824 Joseph "Nicéphore" Niépce (at
left; 1765-1833) created the first semipermanent images using glass plates
coated with a dispersion of silver salts
in bitumen.
• In the early 1830's Niépce's partner,
Louis Jacques Mandé Daguerre (at
right; 1787-1851) accidently discovered
a method for creating a permanent
image on a photographic plate, which
was simply a thin film of polished silver
on a copper base, sensitized by
exposing the silver face to iodine
vapors to form a thin yellow layer of
silver iodide on the surface of the silver.
Niépce's View from the Window at Le
Gras. c. 1826.
• Gernsheim Collection
Harry Ransom Center
/
University of Texas
Retouched image
Chemical details
• Development: expose the plate to a current of
magnesium vapor heated to a temperature of 75°
Celsius.
• The vapor would adhere to the part of the plate
which had been exposed to the light.
• Fixing: immerse it into sodium thiosulfate, which
was used to dissolve the unused silver iodide
• Rinsing: rinse in hot water to remove any
remaining chemicals.
Photogenic drawing
• 1834, William Henry Fox
Talbot (1800-1877)
• Coat drawing paper with
salt solution
• After it dries, add a solution
of silver nitrate.
• Place a leaf, or fern, or a
piece of lace, on the paper's
surface and expose it to the
sun.
• Result: an image
National Trust
Photographic Negative
• August 1835, Talbot made
the earliest known surviving
photographic negative using
a camera, a small photogenic
drawing of the latticed
window in the south gallery
of Lacock Abbey.
Source: William Henry Fox
Talbot: [The Oriel Window,
South Gallery, Lacock Abbey]
(1997.382.1) | Heilbrunn
Timeline of Art History | The
Metropolitan Museum of Art
Later image of Lacock Abbey window
3 1/4 x 4 3/16 in. (8.3 x 10.7 cm), irregular
John Frederick Herschel (1792-1871)
• Fix images using hyposulphite of soda in
1839 (found the hypo could dissolve salts
20 yrs earlier)
• paper entitled "Note on the art of
Photography, or The Application of the
Chemical Rays of Light to the Purpose of
Pictorial Representation," presented to the
Royal Society on 14 March 1839. He coined
the terms “photography’, "negative" and
“positive" in this context, and also the
"snap-shot".
• Images are Herschel by Julia Cameron
(1815-1879) and Hershel’s 1839 image of
his father’s telescope (first image taken on
glass)
First astronomical photos
1st daguerrotype of the
moon by American
physiologist and chemist
John William Draper
(1811-1882) in 1840, 20
minute exposure (later
destroyed by fire).
Solar spectrum
1840, John
Draper
Stars, planets, and moon
• The first star was not recorded
until the night of July 16-17,
1850, when William Cranch
Bond, the director of Harvard
College Observatory, and J. A.
Whipple, a photographer
associated with Massachusetts
General Hospital, took a
daguerrotype of Vega. At right is
an 1852 daguerrotype of the
Moon taken by Whipple.
Need for faster Process
• Astronomers needed a method to produce
better quality images in less time.
• In 1851, Frederick Scott-Archer (18131857) published an article describing the
wet collodion process, although Gustave le
Gray (1820-1884) and Robert J. Bingham
(1824-1870) earlier had suggested and
experimented with the technique.
• higher sensitivity than the early
daguerrotypes, but it needed to be used as
soon as it was made.
Wet Collodion Process:
Chemical details
• Sulfuric acid and potassium
nitrate were reacted on a small
quantity of cotton to create
guncotton (nitrocellulose).
• This guncotton was dissolved in
alcohol and ether with iodides
and bromides of cadmium,
potassium, and ammonium.
• The resulting colloid was spread
on glass plates and evaporated
to leave a thin film of
nitrocellulose impregnated with
bromides and iodides.
Wet Collodion Process
When the plates were dry, they were dipped
into silver nitrate which was saturated with
silver iodide, and this transformed the iodide
and bromide into salts of silver.
This silver halide coating was sensitive to
light, but the plate had to be used
immediately, or else the silver nitrate would
crystallize.
Wet Collodion Process
After the image was taken,
the plate was developed in
a bath of iron sulfate,
acetic acid, and alcohol
which turned the exposed
silver halide grains into
metallic silver.
Sodium thiosulfate was
used as a fixer to remove
the remaining (unexposed)
silver halide grains
the plate was then washed
to remove the chemicals
a coat of varnish was
applied to protect the
image.
picture credits: PBS and http://www.collodion.org/
An example
• Mizar and Alcor were
photographed in March 1857 at
Harvard College Observatory on
wet collodion.
• The 1874 transit of Venus was also
widely photographed on collodion
plates as well as daguerrotypes.
• The collodion plate at right was
taken in Japan by Jules Janssen
(1824-1907), later director of the
Meudon Observatory.
Technological breakthroughs in 1870s
Maddox
1871, Richard Leach Maddox (1816-1902) the first positive dry emulsion for physical
development, using gelatin (a transparent
animal protein)
1874, J. Johnston and W. B. Bolton made the
first negative emulsion for chemical
development
1878, Charles Bennett had discovered a
method by which he could increase the
speed (sensitivity to light) of gelatin-silver
bromide emulsions by aging them at 32°C
in a neutral medium.
1879, George Eastman (1854-1932) invented
a machine to coat plates with emulsion,
so that the plates could be produced in
mass numbers, relatively quickly and
cheaply.
Astronomy advances
• With silver bromide dry emulsion
plates, the first good photographs of
Jupiter and Saturn were made in
1879-1886, and of comets in 1881
(Tebbutt's comet).
• A 51 minute exposure of the Orion
Nebula was taken in September 1880
by Henry Draper (1837-1882)
• 1882, Draper took 137 minute
exposure which revealed the entire
nebula and the faintest stars in it.
• 1872, the first spectrum of a starVega-was taken by Henry Draper.
1880 photo
1882 photo
Astronomy advances
• 1882 Sir William Huggins (who was the
first to show that stellar spectral lines
could be identified with terrestrial
elements, in 1864) took the first
spectrum of a nebula (the Orion Nebula)
• 1899 the first spectrum of a "spiral
nebula - 7½ hour exposure -taken by
Julius Scheiner (1858-1913) with the
Große Refractor of the Astrophysical
Institute of Potsdam Observatory.
• 1882-1886: The first sky surveys were
done at Harvard, each photograph
covering a 15°x15° area of the sky and
reaching stars as faint 8th magnitude.
Scheiner
Emulsion Grain Size
• The first emulsions had grain sizes of about 10
micrometer in diameter.
• Today, emulsions generally have grain sizes
about ten times smaller than the earliest
ones, or about one micrometer, and this
allows for much more detailed photographs to
be taken.
Color Sensitivity
• Hermann Wilhelm Vogel (1834-1898), working in
Berlin in 1873, accidentally discovered a way to make
photographic emulsions sensitive to colors of light
other than blue.
• At the time, green dye was used to soak up reflections
off the back side of the glass in a photographic plate.
Sometimes this green dye got into the emulsion along
the plate edges, and Vogel noticed that the plate in
this area was more sensitive to light of a longer
wavelength or redder color.
• By 1874 Sir William de Wiveleslie Abney (1843-1920)
was able to put together an entire optical solar
spectrum, from violet to infrared.
• Early 20th century, C. E. Kenneth Mees (1882-1960) at
Eastman-Kodak made outstanding improvements in
emulsions and spectral sensitivity. Kodak provided
plates at cost to observatories.
Hypersensitization
•
•
Talbot
•
•
For very faint objects the emulsions react
differently with light which has come in at a
quick rate versus light which slowly filters in.
This phenomenon is known as reciprocity
failure.
The first person to determine a way to partially
overcome this problem was Fox Talbot ( 18001877) in 1843, who discovered that heating
emulsions prior to exposing them increased
their efficiency for short exposures.
50 years later, William Abney and King found
that chilling emulsions made them more
efficient for long exposures.
Among hypersensitizing techniques are water
bathing, pre-exposure, ammoniating, mercuryvapor treatment, and high temperature baking
for several different emulsions.
Eastman
references
• http://www.astro.virginia.edu/~rjp0i/museum
/photography.html
• http://americanhistory.si.edu/archives/d8121.
htm
• http://www.aao.gov.au/images/general/photo
graphy.html#Combination
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