Glossary - Color Management for Photographers - page 438

Gamut: The range of colors and tone a device or color space is capable of
containing, capturing, or reproducing. Gamut is the complete color range
usually pictured as a 3D solid; the gamut is the portion of human vision
that the device can reproduce.
Gamut compression: A systematic method of mapping a larger gamut into
a smaller gamut while ideally retaining as much of the original color
appearance as possible. Converting an image from a large gamut RGB
working space into a smaller gamut CMYK printer space is an example
of gamut mapping. See also Rendering intent .
Generic profile: See Canned profile .
Gray Component Replacement (GCR): A process whereby colored inks,
usually CMY, are replaced with black ink in the color separation process.
GCR replaces CMY inks in both neutral and nonneutral areas with the
correct corresponding amount of black ink. See also UCR .
Halftone: The process whereby continuous tone images are produced
using various sized or spaced dots. Larger dots represent darker areas, and
smaller dots represent lighter areas of an image. Traditionally the dots
were produced by being photographed through a glass or contact film
screen that would break the image into various size dots. Hence the term
linescreen , used to define how fine this halftone dot was created. Low line-
screens produce larger dots. An 85 linescreen halftone dot is typical for
newspress; 133 to 185 linescreen are more typical of offset press work.
HSB: Hue/saturation/brightness; a three-dimensional color model that
describes a color by separating hue from saturation and brightness. See
also Hue .
Hue: Hue refers to the pure spectral colors of the rainbow. Hue is the
term that encompasses all the names we give to specific colors such as
red, blue, yellow, and so on. Hue is the name of a distinct color of the
spectrum (ROY_G_BIV; Red/Orange/Yellow/Green/Blue/Indigo/Violet).
ICC: International Color Consortium. A group of companies such as
Apple Computer, Eastman Kodak, Agfa, HP, and others agreed to create
an open, cross-platform color management solution using ICC profiles.
ICC profile: A standard, cross-platform format used to describe the behav-
ior of a device such as a scanner, digital camera, display or output device.
ICC profiles subscribe to the format developed by the ICC and use the
PCS, which utilizes a device-independent color space to map colors from
device to device. ICC profiles are used in most, if not all, modern color
management systems. See also Device-independent and PCS .
ICC-savvy: A product that works with ICC profiles as specified by the ICC.
Photoshop is an example of an ICC-savvy application. Also known as
ICC-aware.