> > I can see that you postprocessed it with a smooth-filter
> > followed by a sharpen-filter. This is a little trick that
> > cheats us to think it's taken with a good old camera.
>
> can You tell something more about this trick ?

Yes I can. If you take a close look at most photos that are either scanned
or taken with a digital camera, you will notice that there's kind of an aura
or glow around dark objects on lighter backgrounds (in places with sharp
contrast in luminance). The effect will be less visible in pictures that has
been downsized, but usually visible at decent resolutions. The reason for
the effect is not the camera itself, but the post processing: They've
applied a sharpen filter to compensate for a camera that didn't take a
perfectly sharp picture.

You might say, this must have been a cheap camera, but it could also be
because the person who take the photo is shaking a little (just a *little*)
or the lens was not perfectly focused. This happens very often, even with
expensive cameras, but it can't be considered a law of nature so it isn't
something POV-Ray can do on it's own. It's a limitation of todays
technology, but people are used to see these auras on photos, wether they
notice it consiously or not.. So the trick for adding a bit of extra realism
to a raytracing, is to soften the picture, then sharpen it.. Eventually add
some noise.

Hope you got it.  ;o)

Regards,
Hugo

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