Maintaining consistent color
Compared to workflows such as web design, consistent color can be more challenging to achieve in prepress workflows because of the frequent presence of both CMYK and RGB objects in the same job; the different color models require very different color handling. Adobe Creative Suite 2 goes beyond typical color management implementations by designing a “safe CMYK” color workflow that respects and preserves CMYK data even when color-managing the conversion of
RGB images to CMYK in the same job.
In addition to simplifying today’s prepress workflow, Adobe Creative Suite 2 simplifies the administration of color settings across multiple applications and workstations. In
Adobe Creative Suite 2, you can control color consistency from one location (Adobe Bridge), and color settings files are centrally located and easy to share.
It’s important to read this section even if you have already worked with color management, because the changes that support color consistency in Adobe Creative Suite 2 represent significant prepress-friendly improvements upon existing color management implementations. Most importantly, the new safe CMYK workflow means that prepress service providers can be confident that CMYK colors are protected from unwanted conversions when using color management.
Achieving consistent color
Before Adobe Creative Suite 2, it was often difficult to prevent unwanted color conversions when creating output from a document containing both CMYK objects and color-managed RGB objects. Adobe Creative Suite 2 now offers a safe CMYK workflow that also lets users take advantage of the benefits of color management, such as accurate hard and soft proofing.
In the Adobe safe CMYK workflow, RGB and CMYK objects are handled as two separate streams from the time you place files to the time you create final output. When targeting CMYK output,
RGB objects are converted from their source profiles to the proper CMYK output profile, while objects that are already CMYK are left untouched as long as the Preserve CMYK Numbers option is on in the Color Management panel of the Print or Export PDF dialog boxes (it’s on by default). The result is that carefully separated CMYK images are not changed anywhere in the workflow, even when color-managed conversions are applied to RGB images.
All color settings that ship with Adobe Creative Suite 2 use the safe CMYK workflow; their primary differences are in how they handle RGB color and profile mismatch warnings. You can apply color settings to all Adobe Creative Suite 2 products in the Suite Color Settings dialog box in Adobe Bridge. The North American Prepress 2 option is configured to use the Adobe RGB default working space (instead of sRGB) and to display profile warnings for closer monitoring of objects moving through the color workflow.
The North American General Purpose 2 color settings option is designed to be less intrusive and to provide a more consistent on-screen match with applications that aren’t color-managed. This display consistency is achieved by using the sRGB default RGB working space, the default color setting for Adobe Creative Suite 2. As sRGB is simply a document default for RGB objects, using sRGB does not negatively affect placed RGB images that use other color spaces. As long as an
RGB image is tagged with the profile for its actual color space, the image’s original color range is preserved until final CMYK conversion during prepress output. For more information, see
“Using a safe CMYK workflow” on page 17.
Adobe InDesign CS2 also improves the representation of black for monitor display or printed comps, so that black appears consistent between color-managed Adobe InDesign CS2 documents and other applications that aren’t color-managed. For more information, see “Customizing black appearance for monitor display or printed comps” on page 20.
Adobe InDesign CS2 Printing Guide for Prepress Service Providers
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