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Leonard Caillouet Leonard Caillouet is offline
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Default Bit of a Con Really - Follow-up ...

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Leonard Caillouet wrote:
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William Sommerwerck wrote:
The LCD only filters light from the backlight. If you don't have a
full
spectrum white in the first place the you can't expect decent
colour.

Not so. All you have to do is hit the defined points in CIE diagram.
The
Pioneer plasma sets hit them dead-on.

Indeed. None of the major display techologies deliver full spectrum,
nor do they need to.


NT



This is true only if you have custom LUTs or decoding algorithms for a
display based on the relationship between the spectra of the lighting and
the CIE standard observer functions that cameras are generally aligned to
approximate.


What that has to do with it I dont know. If you find an RGB display
with violet output, I'm all ears.


NT



It has everything to do with accurate reproduction of color in video.

What you seem to miss is that the underlying assumption in color
reproduction in video is that the display and the camera both approximate
the CIE standard observer curves for red, green, and blue spectral response.
If this is the case, and you encode properly, you can use a standard
decoding matrix on the display end and get a reasonable reproduction of what
was recorded. If you have a very narrow spectrum on either end, some colors
will be reproduced with less energy than with the proper spectrum. This can
be compensated for using a customized matrix or LUTs.

Again, while it is true that you can make any color within a given gamut
with some combination of R,G, & B, it is NOT true that you will get the
CORRECT color for ALL colors if the decoding matrix is not correct (very
common in many consumer sets over the years, if the gamut is wrong, if the
gray scale is wrong, or if the spectrum is wrong. To get the right mix of
colors for all colors in a given system, you have to play by the rules for
that system. If you change them, such as is the case when you deviate in
spectral response from the CIE curves, you have to make it up somewhere
else. This gets very complicated and is precisely why some people who are
sensitive to color reproduction have noticed that LED based displays have
had trouble with some colors.

Leonard