As files move through a color managed workflow, adjustments are necessary to maintain accurate and predictable color throughout. Color management uses the LAB color model and a profile connection space (PCS), to determine how specific colors (made up of red, green and blue numbers) used by a particular camera, monitor, scanner, or printer are adjusted from input to output.
The CIE, short for Comission Internationale de l'Eclairage (International Commission on Illumination), was founded in 1913 to provide a forum for the exchange of ideas and information and to set standards for how the human eye perceives color. From this commission came the three-dimensional L-a-b model for describing how humans perceive color; it is the foundation for color management systems. The professional artist today can control and predict input and output color results. (L stands for lightness, a for red-green, and b for blue-yellow.)
Input (cameras and scanners) and output (printers) devices use unique sets of numerical data to control how they produce or represent color. A color management system converts (manages) these numbers as the file is moved from one unique device to another unique device or, for example, from a Photoshop file to any type of print-making device. Color management understands the way each device receives color data and represents color data, enabling us to perceive the same color as a file moves through any computer system, camera, scanner, or printer. The color management system uses color profiles and working color spaces to identify and manage these unique color characteristics. A PCS (profile connection space) is the other component integral to the task of converting between input choices and output choices. The PCS is where the color data is examined, edited, converted and sent on its way.
Go to http://www.color.org to learn about the International Color Consortium (ICC) and its work beginning in 1993 to promote an open color management system that is vendor-neutral and cross-platform capable. Prior to the ICC, there was no way to translate color numbers from one unique device to another. The work of the ICC allows artists to choose printers and computers to suit their needs without having to worry about obtaining accurate and predictable results between devices in their workflow. Prior to the ICC, if you wanted an inkjet print matching what appeared on your monitor, you had to use a printer made by the same manufacturer that produced your computer because the language of color production was unique to specific manufacturers and worked only within a manufacturer’s closed-loop system. In years past, there wasn’t a way for a printer made by one manufacturer to understand how color was handled in a computer made by another. This was limiting and locked you into to a specific manufacturer. Artists did a lot of complaining. Adobe felt our pain and beginning with Photoshop v5 rocked our world with a color management system built into the application. It began with the introduction of working color spaces. Professionals and manufacturers are grateful for their contributions and support of our art. Visit http://www.colorsync.com for more information about this topic.