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appendix c: Glossary
Adobe rgb: An RGB working space that provides a relatively large gamut of colors and is well-
suited for documents that will be converted to CMYK.
black: The absence of light. The color that is produced when an object absorbs all light.
calibration: The process of altering a device to bring its behavior into accordance with a known
standard. For example, monitors are calibrated to a specific color temperature, gamma, and
black and white luminance. Calibration is typically accomplished by measuring the behavior of
a device with an instrument, comparing the measured behavior with the standard to which the
device is being calibrated, and then adjusting the device so that it complies with that standard.
camera raw: Any of several formats for photographs that capture all of the raw camera sensor
data, along with metadata that describes the camera settings.
characterization: A method of describing the unique color characteristics (usually in the form
of an ICC profile) of color rendering devices such as monitors, scanners, cameras, and printers.
chroma: Color saturation. Neutral colors have no chroma.
CiE: Commission Internationale de l'Eclairage (International Commission on Illumination).
A standards body responsible for setting standards for color and color measurement.
CiElAb (l*a*b*): A device-independent color space based on the CIE XYZ (1931) color model.
CIELAB describes colors using a lightness channel (L*) as well as two chroma/hue channels
(a* and b*). CIELAB is one of the profile connection spaces used by color management systems.
CiE XyZ: A device-independent color space created by the CIE that describes color using primaries
based on human perception. The primaries are based on how our eyes respond to different wave-
lengths of light.
Cineon: A file format designed to represent scanned images for motion picture workflows.
Data in a Cineon file normally represents printing densities.
colorimeter: A device that measures emitted color using three or more elements (usually red,
green, and blue filters). A colorimeter is typically used with software to create ICC device profiles
for monitors.
color conversion: The process of translating color values from one color space another.
color gamut: The total range of colors produced by a device. A color is said to be "out of gamut"
when its position in one device's color space cannot be directly translated into another device's
color space. For example, the total range of colors that can be reproduced from a film scan is
greater than the amount of color possible on an LCD monitor, so the total gamut for film scan is
said to be smaller than the gamut for the LCD monitor.
color management system (CmS): A software framework that processes application requests for
color-managed color conversions using ICC profiles and CMMs for translation from one color
space to another color space. The CMS also provides lists of profiles and in some cases preference
information to application software. ColorSync on Mac OS®, ICM 2.0 on Windows, and Adobe
Color Engine are examples of CMSs.
color matching functions: The relative amounts of three additive primaries needed to match each
wavelength of light, usually based on the CIE Standard Observer. The human eye, digital cameras,
and scanners all have color matching functions.
color model: A system used to numerically describe colors. Some models include red, green, blue
(RGB); hue, lightness, saturation (HLS); cyan, magenta, yellow, black (CMYK); lightness, a*, b*
(L*a*b*).
Color management workflow in Adobe After Effects CS4
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