scott <sco### [at] scottcom> wrote:
> >    As said, I don't really know *why* this is so. As I have mentioned,
> > with my CRT a 'rgb 0.5' as produced by pov3.7 by default looks about
> > 50% gray when compared to a test pattern, so *in theory* a linear
> > gradient produced by pov3.7 should look linear.

> No it shouldn't - your eye/brain does not see light in a linear fashion. 
>   50% actual brightness from something (as measured in cd/m^2 or 
> whatever) will *not* look half as bright as 100%.  It's no different to 
> a real scene, light bulbs, or an image on your monitor.  It's just the 
> way your eye/brain works.

> An analogy is hearing, a sound with twice the physical power (in Watts) 
> does not sound twice as loud to a human.

  I suppose the fundamental question would then be: "If I say to povray
to produce a linear gradient, should it produce a gradient which is
linear according to light intensity, or according to the perceived
linearity as seen by people?"

  What I'm getting at is that when people specify a linear gradient,
they expect to get a gradient that *looks* linear (rather than a gradient
that might be linear as measured by some device that measures light
intensity).

  As for whether eg. surface shading looks more realistic with the new
gamma handling or the old one, it would be interesting to see some
actual comparisons with photographs. (Note that I'm *not* saying here
that in my opinion pov3.6 is producing the more closer-to-reality
result while pov3.7 is producing something which is way off. I'm
completely honestly interested in actual comparisons with real-life
photographs, to see which one gets closer, if that would be possible.)

-- 
                                                          - Warp

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