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Adobe InDesign Help
Producing Consistent Color
Using Help
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Contents
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Index
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338
The following components are integral to a color-managed workflow:
Device-independent color space
To successfully compare different device gamuts and
make adjustments, a color management system must use a reference color space—an
objective way of defining color. Most CMSs use the CIE (Commission Internationale
d’Eclairage) LAB color model, which exists independently of any device and is an interna-
tional standard for color measurement. For this reason, CIE LAB is considered
device-
independent.
Color management engine
Different companies have developed various ways to
manage color. A color management system lets you choose a
color management engine
that represents the approach you want to use. Sometimes called the
color management
module
(CMM), the color management engine is the part of the CMS that does the work of
reading and translating colors between different color spaces.
Color profiles
The CMS translates colors with the help of
color profiles.
A profile is a
mathematical description of a device’s color space; that is, how the reference CIE values of
each color in the color space map to the visual appearance produced by the device. For
example, a scanner profile tells a CMS how your scanner “sees” colors, so that an image
from your scanner can be accurately translated into the CIE color space. From the CIE
space, the colors can then be translated accurately again, via another profile, to the color
space of an output device. InDesign uses ICC profiles, a format defined by the Interna-
tional Color Consortium (ICC) as a cross-platform standard. InDesign also supports
Microsoft ICM (Image Color Management) profiles and system-level CMS on Windows 98,
Windows 2000, and Windows Me.
Rendering intents
No single color translation method can manage color correctly for all
types of graphics. For example, a color translation method that preserves correct relation-
ships among colors in a wildlife photograph may alter the colors in a logo containing flat
tints of color. Color management engines provide a choice of
rendering intents,
or trans-
lation methods, so that you can apply a method appropriate to a particular graphical
element. For descriptions of the rendering intents available to InDesign, see
“Specifying a
rendering intent” on page 347
.
Note:
Don’t confuse color management with color correction. A CMS won’t correct an
image that was saved with tonal or color balance problems. It provides an environment
where you can evaluate images reliably in the context of your final output.
Do you need color management?
Use the following guidelines to determine whether or not you need color management:
•
Color accuracy in your working environment isn’t required if you rely completely on
prepress service providers and commercial printers for all of your color work.
•
Color management is recommended for maintaining color accuracy in monitor display,
the ability to soft-proof colors, and color consistency in large workgroups.
•
Color management is recommended if you reuse color graphics for print and online
media, use various kinds of devices within a single medium (such as different printing
presses), or print to different domestic and international presses.
If you decide to use color management, consult with your production partners—such as
graphic artists and prepress service providers—to ensure that all aspects of your color
management workflow integrate with theirs.
