RenderElements and OVERRIDE pass

[trick]

I am using PSD-Manager to get masks for all my objects/materials. For some reason PSD-Manager was not activated for the high res renders, so I wanted to use an override pass (No GI, override mat to black VRayLightMTL with refraction, opacity and displacement preserved, Bucket mode) to get all my renderelements as fast as possible. This all works OK (2min render instead of 3hr full render) except for one thing: the masks for objects behind glass (which are OK with full renders; glass refraction set to affect all channels) stay black. Shouldn't this work since I have preserved refraction and opacity in the override material? (Using VRay 6.20.06)

[hermit.crab]

I am using PSD-Manager to get masks for all my objects/materials. For some reason PSD-Manager was not activated for the high res renders, so I wanted to use an override pass (No GI, override mat to black VRayLightMTL with refraction, opacity and displacement preserved, Bucket mode) to get all my renderelements as fast as possible. This all works OK (2min render instead of 3hr full render) except for one thing: the masks for objects behind glass (which are OK with full renders; glass refraction set to affect all channels) stay black. Shouldn't this work since I have preserved refraction and opacity in the override material? (Using VRay 6.20.06)

VRayLightMtl doesn't have Reflection/Refraction options (but it does have both Opacity and Displacement), so those preservations can't be used. Put a black VRayMtl as your override shader and you'll see that it will work as expected.

[trick]

Ah, so the desired preserve properties should be available in the override material !! That was not clear to me. Sadly it takes twice as long with a VRayMtl, but I can still live with that

So when generating masks this way, opacity mapped leaves can be preserved with VRayLightMtl but masks from objects behind glass do not work ? Then for most exterior scenes VRayLightMtl will be good enough.

Thanks

EDIT: By switching off Lights, Hidden Lights, Default Lights and Shadows in the render settings I do get back the 2min rendertime using a black VRayMtl. So in case of emergency, with a standard render preset (important for setting up Pulze Scene Manager) I can render my PSD-masks quickly now for every scene