Chapter 11
Preparing a Document for Prepress
and Printing
Objectives
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Explore color theory and resolution issues
Work in CMYK mode
Specify spot colors
Create crop marks
Create bleeds
Save file as a PDF
Explore Color Theory and
Resolution Issues
Energy from the sun hits the earth in waves:
• X-rays
• Gamma rays
• Ultraviolet rays
• Visual light rays (white light)
Explore Color Theory and
Resolution Issues
• White light broken down into seven distinct
colors (as seen in a rainbow)
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Red
Orange
Yellow
Green
Blue
Indigo
Violet
Explore Color Theory and
Resolution Issues
• Colors in visible spectrum can be broken into red,
green, and blue (primary colors).
– Primary colors cannot be reduced
– Additive refers to the fact that the primary colors
combine to produce other colors
– Red, green, and blue, when combined equally,
produce white light
– True black is the absence of all light
Explore Color Theory and
Resolution Issues
White light
Explore Color Theory and
Resolution Issues
Subtractive primary colors
• Three things can happen when light strikes an object:
– Reflection – when light ‘bounces’ off the object
– Absorption – when light is not reflected
– Transmission – when light passes through an object
Explore Color Theory and
Resolution Issues
• Depending on physical properties of object, varying
amounts of light are reflected, absorbed, and
transmitted.
• Red, green, and blue light not reflected in equal
amounts.
• Color is based on percentages of red, green, and blue
reflected, and the color that combination of light
produces.
Explore Color Theory and
Resolution Issues
Explore Color Theory and
Resolution Issues
• Cyan, magenta, and yellow are called
subtractive primary colors.
• Each is produced by removing or subtracting one of
the primary colors completely.
• Overlapping all three pigments would absorb all
colors.
Explore Color Theory and
Resolution Issues
Cyan is
“minus red”
Magenta is
“minus green”
Yellow is
“minus blue”
Explore Color Theory and
Resolution Issues
• Color printing uses the three subtractive primary
colors plus black to produce a color image or tint.
• The standard color for paper is white.
• Cyan, magenta, and yellow are manufactured to be
transparent.
• The color you see on a printed page is light reflected off
the page.
Explore Color Theory and
Resolution Issues
The color of the printed image is reflected off the paper, not the inks
Explore Color Theory and
Resolution Issues
CMYK inks (process inks) are not perfect.
• Ability to transmit light not perfect.
• In theory, overlapping all three inks should
produce black because no light would be
reflected.
Explore Color Theory and
Resolution Issues
The image on the left was printed with only CMY inks
Black inks add contrast and depth to image on the image on the right
Explore Color Theory and
Resolution Issues
• Illustrator is a vector-based drawing program.
• Graphics you create are called vector graphics.
• Vector graphics are resolution independent
because they are not comprised of pixels.
• You can resize vector graphics without any
concern for quality.
Explore Color Theory and
Resolution Issues
• You can convert vector graphics to bitmap
graphics by a process called rasterization.
• Bitmaps are comprised of a rectangular grid of
colored squares called pixels.
• Pixels is short for picture elements.
Explore Color Theory and
Resolution Issues
Images composed of pixels
include:
• Scanned images
• Digital images
• Rasterized Illustrator graphics
Explore Color Theory and
Resolution Issues
• The number of pixels in a given inch is referred
to as the image’s resolution.
• To be effective they must create the illusion of
continuous tone.
Explore Color Theory and
Resolution Issues
• Effective resolution refers to the resolution of
a placed image based on its size in the layout.
• Relevant only to bitmap graphics because
vector graphics do not have pixels.
Explore Color Theory and
Resolution Issues
If you enlarge a bitmap graphic, the same number of pixels must be spread
over a larger space, reducing the effective resolution
Explore Color Theory and
Resolution Issues
• DPI refers to dots per inch.
• PPI is the correct term for pixels per inch.
• LPI refers to the number of lines of halftone
dots in a professionally printed image. 133150 lpi is standard.
Explore Color Theory and
Resolution Issues
• Standard resolution for bitmap graphics for
Web images is 72 ppi.
• Standard resolution for bitmap graphics that
will be printed is twice the LPI, usually 300 ppi
for high-resolution graphics.
Explore Color Theory and
Resolution Issues
• Resolution of laser printers is 600 dpi or 1200
dpi and is satisfactory for text and lines.
• A resolution of 2400 dpi is required to output
quality images and blends.
Explore Color Theory and
Resolution Issues
• Whenever you print artwork that has
transparent objects such as those that have
blending modes applied or opacities less than
100%, Illustrator flattens it.
• If you are unsatisfied with the look, rasterize it
yourself to see if you get better results.
Work in CMYK Mode
• Color models are mathematical algorithms
that computers use to calculate and manage
the color displayed on a monitor.
• Color models are RGB, CMYK, HSB.
Work in CMYK Mode
• The color mode determines the color model used
to display and print Illustrator documents.
• Two color modes offered in Illustrator:
– CMYK Color – base for color printing
– RGB Color – base for color in light-emitting devices such as TV
or computer monitor, and is the result additive properties of
red, green, and blue.
Work in CMYK Mode
• Color gamut refers to the range of colors that
can be printed or displayed by a given color
model.
• A good monitor can produce a color gamut of
more than 16 million colors.
Work in CMYK Mode
• Spectrum of color viewed by human eye is wider
than any man-made method for producing color.
• CMYK model substantially smaller than RGB model.
• Some colors you can see on monitor cannot be
reproduced by CMYK printing process.
Work in CMYK Mode
• If working in RGB mode and choosing colors,
Illustrator will warn you if a color is ‘out-of-gamut’
and can’t be printed.
• If image created in RGB mode and you convert to
CMYK mode, Illustrator will automatically replace
with closest CMYK counterparts.
Work in CMYK Mode
Out-ofgamut
warning
icon
This color
is out-ofgamut
CMYK color model is unable to reproduce the brightest and most
saturated hues that you can see on your screen
Work in CMYK Mode
• Tints are colors that you
print by mixing varying
percentages of CMYK inks.
• Lightest colors produced
with the smallest
percentages of ink.
Dragging sliders on the Color
panel is referred to as
“specifying” or “mixing” a color
Specify Spot Colors
• Printing is based on the four process colors CMYK,
but not limited to them.
• Working with tints can have problems so designers
and printers use non-process inks to solve problems.
– Color gamut of non-process inks are special premixed inks
– Non-process inks offer consistent color through document
Specify Spot Colors
Non-process inks referred to as:
• Spot color: Refers to non-process inks print on ‘spots’ on
paper where process inks do not print
• Fifth color: Refers to non-process inks printed in addition to
four process inks
• PANTONE color: Refers to a manufacturer of non-process inks
• PMS color: An acronym for PANTONE Matching System
Specify Spot Colors
To load spot colors, use
the Swatch Libraries
menu to select range of
color systems, including
PANTONE, which
appears as a separate
panel.
Specify Spot Colors
Outputting documents with spot colors
• When four color document is printed on printing
press, each color is printed separately on its own
‘plate.’
• When document is printed with four colors and a
spot color, the spot color requires its own ‘plate.’
Specify Spot Colors
• In Illustrator, all spot colors will automatically
be converted to their process match unless
you deselect the Convert to Process option in
Separation Setup dialog box accessed in the
Print dialog box.
Specify Spot Colors
Spot colors are converted to their process match when separated
Create Crop Marks
• The trim size of a document refers to the size
of the finished document.
• The document size is the trim size.
• Crop marks are short, thin lines that you can
use to define areas of the page that you want
be trimmed after the document is printed.
Create Crop Marks
• You can create custom-sized crop marks on
the artboard by drawing a rectangle that is
precisely the same size as the document’s trim
size.
• Click Effect on the Application bar, then click
Crop Marks in the Illustrator Effects section of
the menu.
Create Crop Marks
• Illustrator adds crop marks as effects.
• Like all effects, crop marks are listed on the
Appearance panel.
Create Crop Marks
Create Crop Marks
• Once you’ve created crop marks, you cannot
directly select them to edit them.
• You must first expand the appearance to
select and edit the crop marks.
• Click Object on the Application bar, then click
Expand Appearance.
Create Bleeds
Creating bleeds and safety guides
• A bleed element is artwork that extends to
the trim.
• Build a bleed to extend artwork so that it
exceeds the cropped area by a minimum of
.125 inches.
Create Bleeds
• Artwork can bleed off any one or all four sides
of the trim.
• Create a bleed object with Offset Path
command.
• Or extend existing artwork off the artboard
using the Move command for precision.
Create Bleeds
All elements that
aren’t designed to
bleed should be
kept a minimum of
.125" from trim
edge.
.125" bleed
Save a File as a PDF
• PDF (portable document format) is one of the
most common export formats for emailing
documents and printing high-res output.
• As a PDF, illustrator artwork is complete and
self-contained including all placed graphics
and fonts.
Save a File as a PDF
• You can make a PDF of your artwork using
compression utilities to reduce the size of the
file.
• This results in a low-resolution file, with
lessened image quality, but is beneficial for
emailing to clients.
Save a File as a PDF
You can modify
compression and
other settings in
the Save Adobe
PDF dialog box.
Save a File as a PDF
• When sending your PDF to a professional
printer, you will not want to use compression
settings, because you want the highest quality
file possible.
Save a File as a PDF
• You can modify other settings in the Save
Adobe PDf dialog box as well such as:
– Showing crop marks and printer marks
– Filename, date, time of creation
– Whether it is in the CMYK or RGB color space
Save a File as a PDF
• There are pre-defined presets you can choose.
• You can also create and save your own unique
settings as a preset.
Save File as a PDF
General settings
that you can
modify in the
Save Adobe PDF
dialog box.