| Gamma |
A
mathematical curve representing both the contrast and brightness
of an image. The steepness of the curve indicates greater contrast
calculated as a trigonometric tangent function. |
| Gamut |
The
range of colours that can be captured or represented by a device.
When a colour is outside a device's gamut, the device represents
that colour as some other colour. |
| Gamut
Compression |
The
editing of an image to reduce the colour gamut so that the image
can be displayed or output within the limits of a particular device. |
| Gamut
Mapping |
The
plotting of an image colour gamut into the CIE colour space. |
| Gaussian
Blur |
An
image-softening effect utilising a bell shaped Gaussian distribution
to apply the softening effect. A "Gaussian" curve (a/k/a
"bell curve") is a bell-shaped curve showing a distribution
of probability associated with different values of a variant. |
| GCR
(Grey Component Replacement) |
A
type of process colour separation that determines the amount of
black ink used to replace Cyan, Magenta, and Yellow in areas where
those three inks overlap. |
| Gelling |
1) General
meaning: conversion of a liquid to a jelly. This term is used specifically
to denote the deterioration of an ink, owing to the partial or complete
changing of the medium into an insoluble jelly-like condition, which
is unworkable, even with the addition of solvent. 2) Alternative
to thixotropic. |
| Gicleé
(Fr. "a spraying of ink") |
Term
for fine-art digitally produced prints. |
| Gigabyte |
1,073,741,824
or 1 billion bytes. |
| GIGO |
Garbage
in, garbage out. A computer industry slang term. |
| Gloss |
The
degree to which a printed surface possesses the property of reflecting
light in a mirror-like manner. (Specular reflection). |
| Gradation |
Transition
between two colours or between black and white. Also known as a
gradient. |
| Grain |
The
smallest component of a photographic image. A single particle of
silver or dye cloud. Collectively, the size of those particles. |
| Gravure |
An
intaglio printing process that uses engraved cylinders. Ink is retained
in the engraved areas for printing. It is ideal in long-run work
and prints on most substrates. |
| Green |
One
of the three additive primary colours of light (Red, Green and Blue). |
| Grey
levels |
The
number of steps available to reproduce a colour in an imaging system.
Typically, in an 8 bit system there are 256 grey levels per colour. |
| Greyscale |
An
image containing a range of grey levels as opposed to only pure
black and pure white. |
| Grinning
through |
The showing through of an underlying surface due to the inadequate
opacity of an ink film which has been applied to it.
|
| Grippers |
Clamping
devices that assist in the transport of substrate from a machine. |
