ARRI Projection HDTV - Manual (Page 37)

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Soft clip parameters demystified
Gamut compression can be achieved in general by reducing
the chroma of colors, thus moving colors slightly towards
the gray axis.
In the case of recording CRT monitor images to film, due
to the fact that film gamut reaches its maximum chroma at
lower levels of lightness than the monitor gamut, carefully
reducing lightness also moves colors into the film gamut.
Best results are achieved by balancing chroma and lightness
reduction. The soft clip parameters specify the amount of
change in terms of the perceptual difference between the
two gamut’s, e.g. setting dC.R to 50% reduces red
chroma by 50% of the difference between the pure red
of the monitor and film gamut, respectively.
Both chroma and lightness change depending on hue,
chroma and lightness, so that dark and unsaturated colors
are affected less than bright, highly saturated colors.
For colors at which the film chroma is greater than the
monitor chroma, the chroma difference should be 0 or
negative to gain gamut compression, otherwise gamut
extension would be the effect. This is especially true for
yellow.
5.3 Provided profiles
Provided with the color management are the following
ICC profiles:
profile name :
sony_hd.icm
description :
Sony BVM –D24 class A HDTV studio monitor,
HDTV video safe range
device dependent RGB values :
16 bit RGB values,
representing the SMPTE260M video safe YUV range.
That means:
RGB=0 matches YUV=64,512,512 and
RGB=65535 matches YUV=940,512,512
for 10bit YUV.
profile name :
vision.icm
description :
Kodak Vision print stock projected by a xenon lamp
Color Management
5.3.