Chapter 6 – Glossary of Color Management Terms

From The Standard, Volume 2, 2006, courtesy of Sappi North America.

Achromatic • Hues made from black, gray and white.

Additive Colors • RGB (red, green, blue) uses additive color mixing, meaning that a combination of certain light frequencies are emitted to produce a given color.

Calibration • Establishing a fixed, repeatable condition for a device.

Characterization • The process of creating a profile that describes the unique color conditions found on a particular device.

CIE (Commission Internationale de I’Eclairage) • The international standards organization responsible for setting standards for color and color measurement.

CIE L*a*b* or CIELAB • A mathematical model that describes colors using three synthetic primaries: L*, which indicates lightness; a*, which indicates red-greenness, and b*, which indicates yellow-blueness.

CMM (Color Management Module) • A software component that adjusts the numerical values that get sent to, or received from, different devices so that the perceived color they produce remains consistent. This is considered the “engine” in color management systems.

CMYK • Cyan, magenta, yellow plus black – the colors used for four-color process printing. Also known as process colors.

Colorimeter • An instrument typically used to measure color from computer monitors. It optically measures the relative intensities of red, green and blue light reflected or emitted from a color sample.

Color Gamut • The range of color a device, or color model, can produce. If one device has a larger color range than another, it can reproduce more colors

CMS • Color Management System. This ensures color uniformity across input and output devices so that final printed results match originals.

Color Model • RGB, CMYK and CIELAB are all examples of color models. Each is a means of specifying color numerically, usually in terms of varying amounts of primary colors.

Color Space • The range of colors a color model can produce.

ColorSync • The color management system built into Apple’s Mac OS.

Density • The ability of a material to absorb light. The darker the material, the higher the density.

Densitometer • An instrument that measures optical density.

Dynamic Range • The range of density that a film stock, digital camera, scanner or measuring instrument can detect, usually expressed as optical density (OD) units. The lowest density is termed dMin, and the highest is dMax. For paper, dynamic range refers to the whitest white of the paper and the blackest black that you can achieve with ink on paper.

Flat Color • Colors and tints that are not formulated from standard process colors.

Fluorescence • The ability of a substance such as paper or ink to absorb ultraviolet light waves and reflect them as visible light.

Gamut Compression or Mapping • The process of reducing a large color gamut to fit into a smaller gamut such as print.

G7 • A methodology designed to reliably and efficiently match the visual appearance of multiple devices by defining gray balance and neutral print density curves instead of the traditional method of measuring TVI for color.

GRACoL (General Requirements and Applications for Commercial Offset Lithography) • Guidelines and recommendations for commercial printing developed by an alliance of graphic arts professionals (now called Idealliance).

Gray Balance • Printed cyan, magenta and yellow halftone dots that accurately produce a neutral gray image.

Grayscale • Strip of gray values from white to black. Used by process camera and scanner operators to calibrate exposure times for film and plates.

ICC (International Color Consortium) • A group of hardware and software providers who have joined forces to develop cross-platform standards for color communication and consistency.

ICC Device Profile • The ICC developed this standard format for a data file that describes the color behavior of an input, display or output device, or a color model. The format is referenced to a device-independent color model such as CIELAB.

Match Color • In printing, the duplication of a specified color by using either multiple process colors or special flat colors. Match colors may be defined by supplied samples or by numbers from color matching systems.

Metamerism • The phenomenon where two color samples appear to match under one light source and differ under another.

Out-of-gamut • Colors from one device that are not supported in another device.

Profile • A data file that describes the color behavior of devices like scanners and monitors or defines the color of an abstract color space such as Adobe RGB.

Rendering Intent • A method of handling out-of-gamut colors when matching one color space to another.

Rosette Pattern • The desirable minute circle of dots that is formed when two or more process color screens are overprinted at their appropriate angle, screen ruling and dot shape.

SNAP (Specifications for Newsprint Advertising Production) • Guidelines designed to improve reproduction quality in newsprint production.

Soft proofing • Using your monitor as a proofing device.

Spectrophotometer • An instrument that measures the amount of light a color sample reflects or transmits at each wavelength, producing spectral data.

Stochastic Screening • A digital screening process that converts images into very small irregular shaped and variable spaced dots.

SWOP (Specifications for Web Offset Publications) • Printing standards established by advertisers who had to send copy to multiple magazines and printers and needed to ensure an accurate match. SWOP now also sets precise color standards.

Workflow • A path involving different devices and operations.

Work Space • Choice of colors that are available to edit a graphic; includes both the RGB and CMYK color space.

If you find omissions or errors in this list, please let us know: