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raphii
11-04-2005, 05:00 PM
I am experimenting with hard shadows. Im quite happy with the results. There is only one weakness. I use a distant light with hard shadows and ambient illumination checked. The result is an extrem contrasty image, but it has artefacts. The only way I found to get rid of the artefacts is to set the LOD to redicolous values (e.g. 300 % or more) which causes lots of rendertime. STRANGE: If I use a soft shadow and set the contrast to 1000% I get also a very contrasty image, but without artefacts. But I get much nicer results with hard shadows. Is there a way to get rid of the artefacts without setting the LOD so high???

If you want to try it yourself:
1. Create a light source (Distant, Hard Shadows, switch on "Ambient Illumination" in the Details Tab)
2. Add a Lancscape Object
3. Render
4. Enjoy lots of artefacts

Thanks for your Help

JamesMK
11-04-2005, 05:15 PM
Looks to me only as if you haven't switched to best antialiasing. Hard shadows are raytraced and need best AA, whereas soft shadows use maps and can get away fine with geometry AA.


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raphii
11-04-2005, 05:30 PM
Looks to me only as if you haven't switched to best antialiasing. Hard shadows are raytraced and need best AA, whereas soft shadows use maps and can get away fine with geometry AA.


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Nope... Try my example (you can even render it out with 16x16 Best antialiasing) it still looks %$"'**"'$%

Per-Anders
11-04-2005, 07:11 PM
Which version of C4D are you running? A number of Hard shadow artifacts were fixed in R9.5

raphii
11-07-2005, 07:05 AM
Which version of C4D are you running? A number of Hard shadow artifacts were fixed in R9.5
Currently working on R 9 but Version 9.5 is on it's way.

MJV
11-07-2005, 07:13 AM
Hard shadows don't see phong smoothing, they simply trace the outline of the geometry. There is no fix except to smooth the geometry more. I still get these artifacts in 9.5, so don't count on it to solve it. I suggest you use an area shadow set to .5 degrees (the arc of the sun in the sky) instead if possible.

raphii
11-09-2005, 08:09 AM
I assume you mean soft shadows? (can't use angles with area shadows). But thanks it comes close and renders much faster.

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11-09-2005, 08:09 AM
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