It seems as if mentalray doesn't support light linking? Can someone clarify this. I have a scene where I have some white siding on a building that needs to be unlinked from certain lights. Any help Thanks
i was having the same problem.
I just did my lightLinking in maya as usual and then disabled the Optimize raytrace shadows in the mental ray render globals.
I figured it out you have to go down to the bottom in lightLinking on the left side and deselect the ShaderNodes that the lights are linked to. Hope this helps. Just unchecking the geometry doesn't cut it in MentalRay you also must deselect the Material and example would be materialSG deselect that. Then it should work.