"Kari Kivisalo" <ray### [at] engineercom> wrote in message
news: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.

Okay.  I stumbled across this web page that might be interesting to some:
http://positron.cs.berkeley.edu/gwlarson/vrml  (this is the directory
instead, I had some trouble using links there)

> 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.

Thanks for the reply as well Thorsten.  However the notebook LCD I have here
is probably not worth the effort to try and correct.  I sent the first one
back because of how the screen shifts in brightness from top to bottom.  I
thought getting a TFT Active Matrix kind would be better than it is for this
DELL.  My first experience with them and not a great one.  A trade off from
somewhat fuzzy, yet evenly lit, CRT to polarized-like, yet clear as it gets,
LCD.

Bob H.

Post a reply to this message