Color Workflows for Adobe Creative Suite 3
Table of Contents
- Introduction
- Getting Started
- CMYK Commercial Print Workflow
- Mixed RGB and CMYK Print Workflow
- RGB Photo Print Workflow
- Web Publishing RGB Workflow
- Using profile warnings
- About relative color space sizes
- Glossary
- How Illustrator CS3 uses RGB and CMYK document profiles
- Customizing soft-proof settings
- Simulating print output in CS3 components
- Creating PDFs of proofs and print-ready files
About relative color space sizes
A color space is a variant of a color model used to describe the colors we see and work with in digital /designcenter-archive/articles/cs3ap_colorworkflows (such as RGB or CMYK) and has a specific gamut (range) of colors. For example, within the RGB color model are a number of color spaces: Adobe RGB, sRGB, ProPhoto RGB, and so on. Each device, like your monitor or printer, has its own color space and can only reproduce colors in its gamut. When an image moves from one device to another, image colors may change because each device interprets the RGB or CMYK values according to its own color space.
It’s important to consider the range of color, or gamut, of each of the devices in your workflow and choose a working space that is appropriate.
Adobe Creative Suite 3 components use working spaces that give users common ICC (International Color Consortium) profiles for storing and working with color data. Each ICC profile, including those for standard working spaces, defines a color gamut or set of reproducible colors. The larger the color gamut, the more colors the color space can define.
Color gamuts can be defined using a CIE color model, which is a color-encoding model based on human vision. Plotting a color space gamut in a horseshoe-shaped CIE chromaticity diagram (Figure 33) shows its relative size, compared to other color spaces.
Figure 33. These color gamut plots show the relative sizes of some color device and standard working spaces. The scanner’s gamut is the largest, followed by Adobe RGB, which is nearly matched by the gamut of an inkjet printer. The gamuts of a SWOP printing press and newspaper press are much smaller.
Keep these guidelines in mind when choosing a standard working space profile:
- To keep all of a photo’s original color, choose a standard working space profile that accommodates as much of the original photo’s color gamut as possible. Converting photos to a smaller standard working space or printer profile diminishes some of the color gamut and the impact of the photo.
- To maintain the closest appearance to the original, keep photos in a standard working space that does not limit the range of color of your output device. For example, the color gamut of Adobe RGB is larger than the gamut of most printing presses. If ICC profiles are used when printing, they intelligently reduce the range of colors in the image to match the press’ range of colors.
- To make it easier to repurpose images—using the same image for different types of output that have different-sized color gamuts—keep photos in a large standard working space as long as possible, and convert color at the time of output.
Consider a photo of colorfully clothed sunbathers on a sunny beach. Published in a newspaper, which has a small gamut, the photo loses much of its colorfulness. The same photo published on a website, however, can probably be displayed on monitors with most of its original saturation. Keeping the photo in a larger space than the output device and then converting it separately for the newspaper press and the web, lets each form of output utilize the full range of color of the specific device. However, if the photo is first converted to newspaper CMYK and then converted to sRGB for the web, the saturation lost to the press cannot be regained for the web.
