"Jim Charter" <jrc### [at] aolcom> schrieb im Newsbeitrag
news:3e9cceec@news.povray.org...
> Gena wrote:
> >
> > So let's recap the discussion :)
> > From all those posts and POV-Ray doc we could make conclusion
> > that recommended assumed_gamma is 1. So let's use it.
> >
> > If you feel that image looks too bright or too dark on your monitor
> > with assumed_gamma=1 try to adjust Display_Gamma parameter
> > which is monitor specific (I specified 1.8 for my monitor). Because
> > that parameter is placed in command line we don't have to have
> > gamma-specific sources for each platform.
>
> Attached is a rendering I did with assumed_gamma 1 and Christoph's
> latest version.  I used the chart in the POV docs and decided that my
> monitor's gamma is 2.6.  So I set this as the display gamma in my master
> ini.  I rendered to a png file and that is what is attached.  Now this
> rendering looks overexposed on my monitor.  Presumably it looks good on
> yours?
>
> To get a rendering that looks nice and saturated and contrasty I need to
> set my display gamma at more like 1.6.  So I am still not clear on
> whether the textures are wrong or if my display gamma value does not
> match the gamma value for my monitor.
>
>

sorry, I do not want to disturb 'cause I really don't have the time to join your
project (but I really liked the idea) and I think all important things about gamma
are already mentioned and I do also completely agree with Christoph about
the importance of assumed_gamma 1.0, BUT it seems there is still confusion.
So I have simply done a search'n'replace on ALL files to remove EVERY
ambient statement, did rise the radiosity brightness to 0.85 and did render
it with display gamma of 2.2 (and Jim, do not trust that poor test so much,
2.2 is the typical value for a crt monitor and for a tft and a mac it is usually
lower). Oh, one more thing, note that the texture include files have (for
historical reasons, I guess) also - sometimes quite high - ambient values, so
it is not a good idea to use them directly, so I have also changed the
T_Gold3C used for the cross.
I think with a little tuning of some diffuse values this is the way to go.

The changed files are Stpaul.inc, entrance.inc and ManOnSlip.inc. I guess you
can apply those small changes very quickly but if I should post them I can do.

Just a final note on the png file format: the ability of png to store a gamma chunk
does not mean that every png file contains gamma information. PoV adds the
gamma chunk but e.g. the program Jim did use to create the texture of his pretty
little figure does not.

so long
-Ive

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