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White bright spots

Posted: Mon Apr 21, 2014 7:18 pm
by 3Dimensional
I keep getting these white bright spots at the edges of a device I'm trying to render. I can't show the whole thing but I cropped it to show just the area where this happens, and I enlarged it slightly. This happens on the top edges of this device, and these are rounded edges. The hot pixels setting is at 0%, setting it lower than that makes absolutely no difference for this. As far as I've read in the manual, that seems to be the only related setting.

It seems to me that this might be the sun reflecting on this surface, but as far as I can see there's no way to make the sun not visible to the camera or the reflections. Changing the sun size makes no difference. Is there any way to get rid of this?

Thanks

Re: White bright spots

Posted: Mon Apr 21, 2014 8:46 pm
by mdharrington
these are usually only on specular materials, and they are due to caustics I believe.

PMC kernal was supposed to take care of this, but it seems it only does if ray epsilon is really high...

Re: White bright spots

Posted: Mon Apr 21, 2014 9:02 pm
by 3Dimensional
mdharrington wrote:these are usually only on specular materials, and they are due to caustics I believe.

PMC kernal was supposed to take care of this, but it seems it only does if ray epsilon is really high...
Thanks for your reply. In this case this object only has a glossy material, with a texture of that color, however it happened also when it was just the glossy material.

I'll try PMC, I went with direct lighting because I was told that anything else took much longer to render.

Re: White bright spots

Posted: Mon Apr 21, 2014 9:41 pm
by 3Dimensional
Indeed, PMC does better with those bright spots, but take forever to render. You say a really high epsilon, how high are you talking about?