AO Overide Material problem

V-Ray V-Ray for 3ds Max Issues
1

Something funny I picked up: I have an ambient occlusion material in my overide material slot (Global switches) created the following way: VrayLightMtl with a mix map and then a VrayDirt for the mix amount.
Resultant map shown in the material editor is a white iluminated sphere and when applied it works perfectly - if I use Vray_adv_150SP1_max2008_x64.

As soon as I installed SP2 the resultant material created came out pitch black and ambient occlusion renders out as pitch black!

Please advise.

2

yeah i can confirm this not working under SP2.
For now what you can do is create a vray blend material and apply your color A and color B there in a form of vray light materials, and use dirt as a blend mask.

3

VRayDirt itself acts as a mix map between its two sub-textures, so you can use that directly rather than going through the Mix map.

Best regards,
Vlado