NEC SpectraView Profiler 5, Руководство пользователя

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Profiler
User Manual
von Kries (HPE)
The von Kries CAT assumes that chromatic adaptation is in- deed an
independent gain control of the cone responses of the human visual
system, and that the scaling is based on the ratio of the cone responses
of the illuminants. Visual result: On a monitor calibrated to a higher color
temperature, all colors appear (compared to CAT „None“) a bit warmer
and more saturated. The opposite is the case for monitors calibrated to
a lower color temperature than D50.
lineare Bradford
A widely used newer chromatic adaptation transform is the Bradford
transform. It was empirically derived by Lam from a set of correspond-
ing colors as determined from 58 dyed wool samples with varying
color constancy, evaluated under illuminants A and D65. The original
Bradford chromatic adaptation transform contains a non-linear correc-
tion in the blue region. In many applications, as in SpectraView Profiler,
this non-linearity is neglected. Changes appear less intensive than in
the „von Kries“ method.
CAT02 (von CIECAM02)
This is the latest development in CATs, it’s effect is close to that in the
„linear Bradford“ method. SpectraView Profiler 5 uses CAT02 as a
default.