"William Sommerwerck" wrote in message
...
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.
White LEDs aren't quite there yet are they?

Absolutely true, except that this particular TV doesn't use white LEDs in
its 'revolutionary' backlighting scheme. It uses small RGB arrays, which
is
why I was questioning whether there was any control over the individual
elements in each array, such that the colour temperature of the nominally
white light that they produce, could be varied. Which would then, of
course,
have a corresponding effect on the displayed colour balance. It just
seemed
to me that given they have gone to the trouble of using RGB arrays,
rather
than white LEDs, the reason for that might have been to get a full(er)
spectrum white.

In a very broad sense, the last thing you want is a "full-spectrum" light.
The standard primaries are diluted with too much white as it is.




In a very broad sense you are correct, but in terms of understanding what is
going on with color reproduction in LCD displays ( and others) you are
making a point that is the equivalent of trying to make D65 with an
incandescent lamp.

White is a rather useless term. All "white" has a color and is a mix of
other colors.

Primaries do not get diluted with white. They get desaturated by adding the
other colors. What you want is a spectrum that is correct, not "white," nor
"full spectrum," nor narrow band RGB. Correct depends upon the assumptions
that are made in recording the image, as well as upon the filters and color
decoding that you implement in the display.

As I have said many times, the underlying assumption that video has used is
that RGB spectral densities should follow the standard observer curves.
When you violate that assumption on the display end, you get some unusual
results with some colors and you have to compensate in your color decoder.
The degree to which, and the techniques used are unclear in these sets. The
results are mixed. Given the sloppy nature of color decoding and color
management in consumer displays in general over the years, however, these
sets are likely to be perfectly acceptable to most consumers. They are
likely better than much of what they have been viewing in the past by quite
a margin. That does not mean that they are going to accurately reproduce
color. Most consumers and most of the posters here would not likely know
( and may not prefer ) accurate color reproduction in a display if they were
to happen to see it.

Leonard