Hi everyone
Trying to do a iron wiring door.
So I made a VRay mat with black and white grid refract bitmap, index to 1 and no reflection.
The prob : I can see everything through the “opacity holes” (or “refract holes”) instead of the background ?
Seems like : I can’t see a background environement bitmap through an opacity map.
Anyone helps ?
why dont you do it with a standard mat?
in that mateial place your background into your environment slot
unless your using vrays override reflection refraction then your screwed and need to use standard material. if like it that the material environment slot overrides the vray override reflection refraction slot in the render dialogue box
Ok, if I understand the solution is to use standard mat.
(I’m surpried of this limitation and I still don’t understand why this is happening…)
… I wanted to use VRay mat because it’s “faster when using VRay engine”.
Anyway, thanks for your help ! 
You should just need to increase the Max Transparency levels, if 100 is not enough you can follow the link below my post and try the MTO script to go higher.