Glossary of terms

Technical terms simply explained

gamma gamma gradation adjustment of a monitor; describes the relation of the decimal logarithm of the output to the input values (y = lg o / lg i), specifically of the RGB values of the input signal to the resulting luminances of the RGB monitor pixels. In Microsoft the value 2.2 is generated, from Apple OS X 10.6 also on the Macintosh, which up until this OS worked with 1.8. For soft copy proof monitors, the Fogra recommends 1.8 or “L-Star” gamma (brightness component L* from CIELAB) in accordance with the gradation in the eciRGB color space. For example K-Flow SMARtt or wobe-team proof servers optimize at L* for the hardware calibration of wide-gamut soft copy proof monitors.

gamut gamut see color gamut

gamut mapping mappage des gammes, mise en concordance des couleurs ICC color management procedure in the course of which a device color space is represented in another device color space. Mapping means that this transformation can be effected according to various regulations; see rendering intents, clipping

GCRgray component replacement sélection achromatique de couleurs color separation file of the UCR-modified chromatic composition, in which the CMY color separation shares in the entire range of the three-color gray are replaced by a “long black”. In UCR without gray component replacement, the gray components would only be replaced in the image depths with a “short black” – see also black.

generic (device) profile profil generique see Tables I-2 “ICC profiles classification” on page 56

German Media Standard Print Instructions by the bvdm and the Fogra relating to contract color-proofed data and proof preparation in accordance with ISO 12647 as well as PDF/X data structuring.

German standard color chart table des couleurs DIN intuitive color order system (DIN 6164) in a spherical sector color solid with transparent, matt and glossy color test charts; parameters: T hue number from 1 yellow to 24 yellow green clockwise, S saturation degree from 0 achromatic to a maximum of 16, D darkness level from 0 white to 10 black; color difference formula