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plix
10-18-2006, 06:32 AM
Hello all,

I have a quick question about mental ray, and using Raytraced Shadows. Currently my scene is set up with 2 photometric lights, GI/FG on. I went to test out my lighting, and when I turned on Raytrace Shadows, I get this weird blotching all over my model. The shadows are there, but there is also, what I can only describe as a "spatter" all across my model.

Its only there when I turn on Ray Trace or Adv. Ray Trace, but when I switch back to Shadow map, the effect is gone. Been using the SSS shader, Im really stumped, I thought it might be my shader at fist, but trying out many different ones, I ended up with the same effect. Tried different lights, with the model, and same thing. Im wondering if it might be something in the Render Settings? Im not very familliar with them.

Im really quite new to MR, so any help will be greatly appreciated

Thank You :)

Oh, using Max BTW!
gringer
10-18-2006, 09:21 AM
Hey man,

There was someone a little while back who had similar problems. It indeed sounds like a render setting issue with your photons/final gather.

Check out this thread :

http://forums.cgsociety.org/showthread.php?t=412089

I hope it gives you a little more insight. Otherwise, do a quick search with the search button above and look for something like... GI spots or something like that.

Good Luck :D
plix
10-18-2006, 03:42 PM
Well,

Thanx for the input Gringer. :) Was somewhat helpful. I went back, closed down max, started a fresh file, and merged my objects in. It was still there. I turned off FG/GI and its still there. So I can say, I dont think the problem is coming from the render settings, but again, Im pretty new.

I tried remaking my lights, and the effect was gone, until I turned on raytrace shadows. Then it was back.

Hopefully someone has some more on the problem, until then, Ill be trying to tweak. Ill upload some pictures of my setup and render. Please excuse the "unfinishedness" of it :)

http://picserver.student.utwente.nl/v/0ZT127BJQ00Yhttp://picserver.student.utwente.nl/v/I55NJ01CXRM8

http://picserver.student.utwente.nl/v/0ZT127BJQ00Y

http://picserver.student.utwente.nl/v/I55NJ01CXRM8
JeffPatton
10-20-2006, 03:20 AM
Are you by chance rendering from a front view instead of a camera or perspective viewport? If so, that's the problem.

See post #2, point #3 here:
http://forums.cgsociety.org/showthread.php?t=303284

If you are using a camera or perspective viewport, then is there the chance of coplaner faces on your mesh?
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10-20-2006, 03:20 AM
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