Gcr; Advantages & Problems Of Gcr - Microtek ScanMaker 6400XL Reference Manual

GCR

Gray component replacement is a variation on undercolor removal. The theory
is simple: Whenever amounts of cyan, magenta, and yellow are present in the
same color, that color has a gray component. Some or all of this gray component
can be printed with black ink while maintaining the original color appearances.
In contrast to UCR, GCR involves a more general color replacement, with black
being substituted over all colors.
The neutral center of both diagrams looks the same. With more GCR applied,
less color ink and more black ink produces the same color.
Advantages & Problems of GCR
The main advantage of GCR is it reduces the effects of variations on press, so
when ink coverage varies, the colors become slightly lighter or darker, rather
than changing hue.
Increased amounts of GCR also allows your printing company to use a
somewhat higher proportion of black ink, thus reducing cost—which saves you
money.
High levels of GCR and/or UCR expand the overall gamut, so darker and more
saturated colors are achievable. However, with too light GCR you may not get as
saturated a color as with higher levels of GCR.
Kodak Color Management System C-9