Chromatic Adaptation - NEC SpectraView Reference 241 User Manual

Profiler
User Manual
16-bit LUT based
In this profile type, the gamut of a device will be described in a table of a
defined number of points. All other color values will be interpolated. This
allows to describe non-linear behavior of a device. The size of a LOUT
profile can be some- where between 200 KB and more than 2 MB.
With 16 bit encoding, the accuracy of a LUT profile will be increased
dramatically (256 times more accurate), while the size only doubles.
That's why SpectraView Profiler offers 16 bit LUT profiles only.

4.6.2 Chromatic adaptation

Chromatic adaptation is the ability of the human visual system to
discount the color of the illumination and to preserve the appearance of
an object. Chromatic adaptation can be observed by examining a white
object under different types of illumination, such as daylight (blueish)
and incandescent (yellowish). The white object retains its white appear-
ance under both light sources, as soon as the viewer is adapted to the
light source (discounting the illuminant).
Within the ICC color management system, D50 is the reference illumi-
nant. Should a monitor be calibrated to a different white point (e.g. D65),
all colors displayed on this monitor need to be converted so that they
appear like they were being viewed under D50 lighting.
Such transformations are called Chromatic Adaptation Transforms
(CATs). There has been a significant amount of research in determining
CATs that are able to accurately predict color appearance across differ-
ent illuminants. The transforms currently in use are based on minimizing
perceptual error of experimental corresponding color data sets.
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