Operating Manual

OPERATING MANUAL
Colorant calibration
series
dE GretagMacbeth
A colorant calibration series consists of a selection of calibrations of various
colorants using the same substrate, the same transparent white and the same
production process. As a rule, one colorant calibration series is allocated to
one assortment.
dE GretagMacbeth is a quality criterion for using ink leftovers. Among other things,
it takes into account the fact that it is very difficult to achieve a pure ink with
a dirty ink leftover.
GretagMacbeth-Optimum Sorting criterion for recipe quality. The sort value is a compromise (weighted
summation) of color distance, metamerism, and further criteria (e.g. number of
colorant components). In the case of a recipe correction, the additional ink
quantity is taken into consideration too.
Ink film thickness
Ink leftover
Ink mixture
Metamerism
Remission
Scattering
Surface coverage
Weight per area
Every assortment is assigned an average ink film thickness. The film thicknesses
(weight per area) of the recipes calculated are related to the average weight
per area (=100%) of the current assortment.
Ink of known or unknown composition left over from previous jobs and used for
the production of a current target color.
Ink mixed in accordance with a recipe in order to produce a pattern.
Measurement of the difference of the remission curves of two colors which
look the same under a given form of lighting (e.g. electric bulb light, daylight).
Only colors which display the same remission curves (M=0) will be perceived
as the same under various light sources.
Ratio of the light reflected from a color to the light reflected from ideal or paper
white, depending on wavelength. The range extends from 0 to 1. The value 1
means that the color reflects as much light as ideal or paper white.
When light passes through an ink film, it is scattered to a greater or lesser degree
by pigment particles, depending on the thickness of the film and the wavelength
of the light. Absorption and scattering together produce the optical effect of
a color.
Area of the substrate covered by ink.
Every assortment is assigned an average weight per area. The film thicknesses
(weight per area) of the recipes calculated are related to the average weight
per area (=100%) of the current assortment.
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28 • Glossary