3D Max - Mental Ray Matte/Shadow/reflection problem

[deathevor]

Hi,

 

I have such problem.

 

Here's the example of the scene:

By deathevor at 2011-02-10

 

I've used mr Sky Portal and rendered it with Mental Ray (Final Gather and GI ON).

 

I also rendered Diffuse and Shadow pass, and everything worked ok.

 

But, my aim is to render the same image with Matte/Shadow/Reflection Material on the ground plane. (For later compositing on to Video footage)

 

So that what I've get.

 

1) Rendered picture - Ok

 

By deathevor at 2011-02-10

Here's an Alpha channel for it. And first problem is that it doesn't have the area with reflected light in the front of the cube.

By deathevor at 2011-02-10

 

2) Shadow Pass - Fail (just empty RGB and empty Alpha channels)

By deathevor at 2011-02-10

[deathevor]

3) Diffuse Pass - Fail (Some glitches + Shadow pass)

By deathevor at 2011-02-10

And basically the alpha channel for Diffuse pass is the same as for Render

By deathevor at 2011-02-10.

 

So really I can't make it work at all. I've tried with different lights (Phonometric, Daylight, Standard lights), with FG and GI off, different materials(Standart and Mental Ray) . But still the same result, Diffuse contains shadow pass and Shadow pass sometimes has some information, but mostly it's glitches.

 

Does anyone can suggest the way to make it work?

 

 

I also want to ask about this - Which Pass should I use to render this part separately from others? (I will remind that on Renderer and Diffuse pass the alpha didn't contain this area)

By deathevor at 2011-02-10

 

 

Thanks

[JonRashid]

I don't know if this will help but I have been having weird problems with matte shadow planes. If i put a duplicate object just below my ground plane with a normal material on it things seem to sort themselves out.

[deathevor]

Hi,

 

If you mean this,

By deathevor at 2011-02-12

 

Doesn't work for me.

 

And here's the shadow alpha channel-

By deathevor at 2011-02-12