Hi everyone! I have a problem rendering the front of a BMW car I have modeled, I am using MR with Final Gather, Ray Trace and an IBL node. The problem is that somehow when I render with Mental Ray the front part of the car displays the whole of the grid, like if the front was transparent or something which it isn't, I don't have this problem when rendering with Maya as you can see. All the objects in the scene are nurbs.

Could you help me please? thanks in advance