Patrick Elliott  wrote in message
<MPG.201c800845c4c970989fd5@news.povray.org>:
> Umm. Ok... But, from a purely practical standpoint, even if changing the 
> effect, you get clipping, instead of correctly adjusted colors. Its like 
> adjusting the volume of a raw audio file format, instead of turning up 
> your speakers. If "any" part of the sound is low enough to fall below a 
> certain threshold and you adjust down, or it goes above a certain 
> threshold and you adjust up... it ends up eating part of the *actually* 
> waveform. Same with Gamma and software based solutions to it. That is 
> what I was getting at.

You are wrong. As someone already pointed, the gamma does not affect the
black and white points. It is a one-to-one mapping between the minimum and
maximum intensity level. It stretches the dark values, and compresses the
light ones, but there is no clipping whatsoever.

What there is, on the other hand, is loss of precision in the part that gets
compressed. For a gamma of 2.2, for example, value 0.5 becomes 0.73, which
means that, on the discrete scale, the two lower bits of the light colors
are lost.

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