View Full Version : Strange Transparency problem in Mental Ray

02 February 2005, 05:15 PM

I've been looking through the boards and their history and can't seem to find anyone with this problem. All I'm doing is turning on Mental Ray, and my renders of non-transparent objects are coming out transparent. It doesn't seem to have anything to do with the lights, textures, materials or Render Global settings--I've tried several different of all of these. I've used mental ray before without this problem, on a PC, now I am using a (very nice) Mac, if that has anything to do with it (don't know why it would). Anyone know what to do about this?

02 February 2005, 05:58 PM
Figured out the problem! I forget that I had attached an oversampling lens to my Camera, not really knowing what it does. I guess that's what it does. So does anyone know where they give a good explanation of all these new exciting mr shaders and lenses?

02 February 2005, 08:04 PM
Oversampling lens shoots additional sample rays in the same direction which can help avoiding artifacts when using, e.g. glossy reflections. Intentionally they invented it for use with the path_material, but thats another story. Actually there wouldnt be any need for it since increasing the general sampling level increases the samples token per pixel as well which is sufficient for usual needs.
Oh, and you just forgot to turn off scanline. Usually lens shaders turn it off automatically, not so the oversampling lens. ;)

02 February 2005, 11:12 PM
Thanks! That works beautifully. :)) and i've been playing with sampling levs. all day which seems to help a lot.

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