"Bob H." wrote:
>
> If I set that to 2.3 though, which is what I get for the LCD screen

LCD and gamma don't mix. Gamma correction is for CRT only.

The response curve of non compensated LCD displays is totally
different from CRT response and trying to measure or apply
gamma with that hardware won't do much good.

I know there are TFT displays that emulate sRGB CRT and those
are hard wired to gamma 2.2. They can be used for graphics work
but the LCD displays I have seen have been non compensated
and unsuitable for editing graphics.

So, if the manual that came with the hardware doesn't mention
anything about sRGB, CRT or gamma emulation forget gamma.

Quick search produced this review about LCD projectors. What is
said here applies also to LCD displays. In short, LCD displays
are problematic.

From http://www.zdnet.co.uk/pcmag/labs/2000/04/projectors/21.html
----
Gamma is a critical parameter for any display product because it
determines how accurately tonal values are reproduced. Although
this might not be so important for high-contrast business
graphics, it's important for the reproduction of natural
images--high-quality images of fine art, for example. Displays
with response curves that follow a power curve
(but with the 'wrong' exponent) can be corrected to the desired
curve. However, some display products exhibit black and white
compression, resulting in an S-shaped curve. Unless this can be
removed by manipulation of the brightness and contrast controls,
images displayed by these products can't be improved purely by
simple gamma correction. 

The gamma characteristics for many of these projectors show large
deviations from the ideal, and the controls that relate to gamma
contrast and brightness were difficult to set. In this review, the
Philips Hopper XG10 and, to a lesser extent, the Toshiba TLP651E
both have S-shaped gamma curves. 
----



_____________
Kari Kivisalo

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