> Something is bugging me. Namely the question why there's spent so much time in
> improving radiosity, sslt, photons etc. while an essential thing is still
> missing in my eyes. You can use the best radiosity and area light settings and
> end up with a render that is still looking somewhat artificial.
> Correct me if I am wrong, but isn't it a fact that povray has always suffered
> from a linear lighting model?
> My eyes are longing for a little bit of non-linearity :)
> And I don't think it would be that hard to implement into the main program. As
> far as I know Megapov has such a feature, called 'tone mapping'.
> I found out a way to simulate this in the official version, it's a bit dirty but
> it works for me.
>
> The trick is to reflect the whole scene in two small spheres centered at the
> camera location and make use of the 'exponent' keyword to control the light
> intensities. (I call it a dirty solution because I don't think that it would
> work well with focal blur, although I haven't tried it yet)
>
> I don't know if this is pysically correct in any way, but the resulting renders
> look more authentic and believable to me than general pov renders.
> And as a positive side-effect, the images look more colorful and less
> 'washed-out' as you can convince yourselves by looking at the attached images.
>

To have physicaly correct, you need to use linear colour space. You can 
always alter the end image if you want.
Some use an assumed_gamma of 2.2 or srgb.
You can also set the file gamma to some arbitrary value, like 2 or 3 if 
you want.

Your cornel cox tone altered image have to much saturation compared to 
the original cornel box. In fact, the original render is also slightly 
oversaturated...

In your second image, the only notable difference is in the sandy ground 
in the background and a slight yellowish cast in the lower part of the 
sky. If you tint the fog slightly yellow, you'll get roughly the same 
effect.

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