Working With Color Profiles; About Color Profiles - Adobe PHOTOSHOP CS2 User Manual

In general, you have the following choices for handling colors when creating PDF files:
(PDF/X-3) Do not convert colors. Use this method when creating a document that will be printed or displayed on
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various or unknown devices. When you select a PDF/X-3 standard, color profiles are automatically embedded in
the PDF file.
• (PDF/X-1a) Convert all colors to the destination CMYK color space. Use this method if you want to create a press­
ready file that does not require any further color conversions. When you select a PDF/X-1a standard, no profiles
are embedded in the PDF file.
(Illustrator and InDesign) Convert colors that have embedded profiles to the destination color space, but preserve
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the numbers for those colors without embedded profiles. You can manually select this option in the Output section
of the PDF dialog box. Use this method if the document contains CMYK images that aren't color-managed and
you want to make sure that the color numbers are preserved. (See "Using a safe CMYK workflow" on page 256.)
Note: All spot-color information is preserved during color conversion; only the process color equivalents convert to the
designated color space.

Working with color profiles

About color profiles

Precise, consistent color management requires accurate ICC-compliant profiles of all of your color devices. For
example, without an accurate scanner profile, a perfectly scanned image may appear incorrect in another program,
simply due to any difference between the scanner and the program displaying the image. This misleading represen­
tation may cause you to make unnecessary, time-wasting, and potentially damaging "corrections" to an already satis­
factory image. With an accurate profile, a program importing the image can correct for any device differences and
display a scan's actual colors.
A color management system uses the following kinds of profiles:
Describe how the monitor is currently reproducing color. This is the first profile you should create
Monitor profiles
because it is absolutely essential for managing color. If what you see on your monitor is not representative of the
actual colors in your document, you will not be able to maintain color consistency. (See "To calibrate and profile your
monitor" on page 265.)
Describe what colors an input device is capable of capturing or scanning. If your digital
Input device profiles
camera offers a choice of profiles, Adobe recommends that you select Adobe RGB. Otherwise, use sRGB (which is
the default for most cameras). Advanced users may also consider using different profiles for different light sources.
For scanner profiles, some photographers create separate profiles for each type or brand of film scanned on a scanner.
Describe the color space of output devices like desktop printers and a printing press. The
Output device profiles
color management system uses output device profiles to properly map the colors in an document to the colors within
the gamut of an output device's color space. The output profile should also take into consideration specific printing
conditions, such as the type of paper and ink. For example, glossy paper is capable of displaying a different range of
colors than a matte paper.
Most printer drivers come with built-in color profiles. It's a good idea to try these profiles before you invest in custom
profiles. For information on how to print using the built-in profiles, see "Letting the printer determine colors when
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