news:c4lvc1-

>To me this seems like C4D is using a non-raytracing technique for
>antialiasing here.  This would explain why it only works on the directly
>visible surfaces.

This is quite probable. In fact C4D has a "geometry mode" aa which is
extremely fast but totally unusable when ray-traced shadows are used (they
don't get aa at all!). I guess that the "best mode" I used here is actually
a combination of POV-Ray-like aa (for raytraced parts) and non-raytraced aa
(whenever possible). As we can see, it results in bizarre discrepancies when
the overall aa quality is bad but the main point is that this type of system
offers a lot of room for compromises between quality and render time.
Working on a "real" C4D scene, I was able to cut down the render time by 35%
(from 49 hours to 31 hours) using a combination of low GI and low aa for
some elements, with an acceptable loss on quality on those.

> But using +a0.0 is completely unfair towards POV, you turn of the
> adaptive antialiasing this way - of course the render is incredibly
> slow.  Using +a0.1 instead renders ways faster (about 20x!) and looks
> better than your 16 seconds sample i think.


that C4D uses (by default) some sort of jittering, different from POV-Ray's,

without noticeable improvement.

I had tried +a > 0 first but it doesn't resolve the problems on the top of
the sphere (little white spots). They only disappear with a0.0, which is
something I would have to do in real image. In fact, I had to use +a0.0 with
C4D too to get rid of it, so it wasn't so unfair (and shows that C4D and
POV-Ray are extremely close here) ! In any case it didn't try to compare
POV-Ray and C4D here about speed issues, just to see how I could get the
best of both apps.

G.
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