PC Hardware in a Nutshell, 3rd Edition

Using Color Management

Getting consistent color across a wide range of peripherals, including monitors, scanners, and printers, is nontrivial, a task made more difficult by the diverse means used for producing color. Monitors produce color by illuminating phosphors. Printers may produce output that uses transmitted or reflected light to produce color by means of dyes or pigments. Scanners may capture either transmitted or reflected images. The color temperature of the lighting used to produce or view an image differs according to its source, and the gamma (in simple terms, contrast) varies with the device. With so many variables in play, the colors on your monitor are likely to be only an approximation of the original colors you scanned, and printed output is likely to differ substantially from both the original and the image on your monitor.

The different methods used to produce color mean that it is impossible to render color with complete consistency. A printed copy, for example, simply does not have the dynamic range that a transparency or monitor image has. But for those doing prepress work, some means of minimizing those differences is needed. To address this problem, Microsoft introduced Image Color Management (ICM) with Windows 95. ICM organizes the characteristics of each device (e.g., for a scanner, the color temperature of the light source and the gamma of the image sensor; for a printer, the reflectivity characteristics of its various inks) and uses those stored characteristics ...