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Jellby wrote:
| According to this, more samples -> brighter media.
	That is correct. If you push this to the extreme, you'll get this
image (10 samples):
http://jeberger.free.fr/mpov/sphere_bl.png

	Increasing the number of samples (to 200) gives this one:
http://jeberger.free.fr/mpov/sphere_no.png

| But I see the opposite,
| as if the influence of the samples was "averaged" (since most
samples are
| deep inside, the effect of the surface ones is weaker). I would have
| thought that the sampling algorithm (and colour calculation) would be
| smarter than that, but maybe that's not so easy...
|
	Do you have a sample code that produces this effect?

|
|>BTW, you
|>shouldn't increase the number of samples too much. Instead you should
|>increase the aa_level and possibly decrease the aa_threshold. This
|>will ensure that the additional samples get taken in places where
|>they will have a useful impact on the result.
|
| I couldn't get the same effect... Even if the "darkening" due to many
| samples (or intervals) is an artifact, I didn't find a reliable way
to get
| what I needed other than increasing the number of samples.
|
	It takes some trial and error, but it should be possible to get the
same effect with a much faster render. Of course, it all depends on
whether you can afford to waste more time fiddling with the
parameters or simply letting the computer render in the background
while you're doing something else ;) To make accurate comparisons,
you also need to make sure that the maximum number of samples is the
same in both cases (I'm not talking of the second parameter of the
"samples" keyword here, but of the number of potential samples which
is something in the order of min_samples * 2^aa_level). Then if you
set aa_threshold to 0 the results should be the same (and take
*forever* to render) so all you need to do is find a value that's low
enough to get the effect you want while not being exactly 0.

	Note that this only applies to subsurface scattering simulations: eg
in cases when you have a very dense nearly uniform media. If you have
a density with areas of very dense media and other areas that are
empty, you will need the increased number of samples

		Jerome
- --
******************************
*      Jerome M. Berger      *
* mailto:jbe### [at] ifrancecom *
*  http://jeberger.free.fr/  *
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