(This seems the most appropriate place for that post - I hope it will be
read by the responsible people)

I wanted to make some additions to the "6.11.3 Assumed_Gamma" topic in the
working-docs included with Mac 3.5b8, which didn't explain things very
clearly (or even correctly). I now see that most of that is already fixed in
the current online version, but one thing is still not clear enough in my
opinion.

What I was missing is basically the following paragraph:

> Before we go to the following sections, that explain more thoroughly what
> gamma is and why it is important, a short overview of how gamma works in
> POV-Ray: 
> 
> no assumed_gamma in scene :
>   No gamma correction is applied to output file.
> assumed_gamma 1 :
>   Gamma Display_Gamma is applied to output file.
>   If Display_Gamma is not specified, 2.2 is used.
> assumed_gamma G :
>   Gamma Display_Gamma/G is applied to output file.
>   If Display_Gamma is not specified, 2.2/G is used.
> Recommended value for assumed_gamma is 1.

What still is not clear to me from that is in which direction "applying"
goes. You shoud write something like

 output_file_value = calculated_intensity ^ (assumed_gamma/Display_Gamma)

(or equivalently
 output_file_value ^ (Display_Gamma/assumed_gamma) = calculated_intensity
to stay with your "applied Gamma")

which is the correct direction as I found out by experimenting.

 -Christian

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