George Pantazopoulos wrote:
> 
> It would be a great feature for creators of realistic, high-dynamic range
> scenes ( with 1/r^2 lighting falloff ), to have POV-Ray be able to
> automatically compress the dynamic range of the output image, as seen on
> this web page: http://www.luxlab.com/c/compress.htm It would be especially
> handy for animations.

Automating this is not trivial but logarithmic or some other transfer
curve with adjustable compression factor may be usefull. The curve
presented on that page doesn't fit all cases. It's just an example to
break the 100% mental limit. For low contrast scenes there is dynamic
range expansion. Just flip the curve around the diagonal. I see these
as special cases of tonal range mapping.

Tweaking the curve by hand yields the best results. It's like working
in the dark room controlling the development, exposure and whatever
else photographers do there :)


_____________
Kari Kivisalo

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