OK. I'm rendering out a scene which uses transparency maps on nurbs planes. The file texture used has an embedded alpha channel that seems to be working fine when I render with maya software; I can even turn on texture mode (6) in perspective view and actively see the effects of the transparency map on the planes. However, when I render out with mental ray (Production/FinalGather)I can see a cast shadow from the edges of the plane. It's as if the alpha map's value for black isn't completly black. I've checked and double checked but to no avail. I've seen but on tutorial addressing this which suggested 'nesting' a shader within a shader using a BlendColors node. I attempted to follow, but the instructions had some errors regarding the proper connections in the Hypershader so I was unable to get it to function properly. I've been banging my head for a month; Any help would be greatly appreciated.