Problem with the redirect Shader

[nvseal]

Has anyone encountered black spots like in this render before? I think it the redirect shader is the cause but I can't figure out what it is.

[Oshyan]

Looks like it might be overlapping or extreme displacement. I'm not sure of a fix besides an update to the renderer or simply reducing/adjusting the displacement.

- Oshyan

[efflux]

I've had this problem and I've seen it in other renders. Specifically in my case it was when I was displacing negatively. It was ray traced shadows. When I turned that off the problem vanished. It seems to happen when geometry is squeezed a lot.