POV-Ray : Newsgroups : povray.beta-test : png gamma error : Re: png gamma error Server Time
31 Jul 2024 06:23:03 EDT (-0400)
  Re: png gamma error  
From: Kari Kivisalo
Date: 25 Sep 2001 11:12:50
Message: <3BB09F2D.EAB9E5EB@engineer.com>
"Bob H." wrote:
>
> Does this mean only a LCD is liable to be okay for setting both display and
> assumed gamma to 1.0?  Or is that okay for a CRT too?  I take it the answer
> is no.

When assumed_gamma=Display_Gamma the samples written to the image file
are linear. Easier way to make this happen is not to use assumed_gamma
at all.

It all depends on whether you want gamma correction or not. Because
povray can't do correction for LCD displays you have to find another
way to do it and have povray output linear samples. Most of the time
it's sensible to enable gamma correction when working with CRT.

You are of course free to use any means to get the image look good on
LCD but...

Then there is the problem of publishing images designed on LCD. Because
99% of images are not viewed on LCDs the LCD correction has to be removed
and (preferably) gamma 2.2 applied before publishing. When using 8 bit
samples this means the image will be in pretty bad shape after all these
conversions.


_____________
Kari Kivisalo


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