shadows are always opaque when using matte/mtlwrapper

[stayinwonderland]

So I have my objects on a plane, and the plane is using the typical matte technique of using VrayMtlWrapper and the alpha set to -1 etc.

 

plane is set to not cast shadow, otherwise normal.

 

when I render, it renders out everything except the plane, which is good, but in the alpha channel the shadows are as opaque as everything else i.e. solid black when I save them out.

 

Any ideas where I'm going wrong?

[Corey Beaulieu]

On the matte properties are you ticking "Shadows" and "Affect Alpha"?

 

Can you maybe post an image if it isn't that?

 

The only other real issue could be if you are using a Standard material.... They are not supported by the wrapper.

 

IDK I'm all guesses.

Edited May 17, 2016 by CoreyMBeaulieu

[stayinwonderland]

yeah all that checks out fine. Material isn't standard either. Here's a screen shot of the material, the alpha channel and the vray properties.

 

 

The whole thing is solid white with no difference in any cast shadows.

[Corey Beaulieu]

hmm... it does all seem on the up and up, but it also seems like I do see a bit of gradient to the alpha. Not everywhere, but especially in the bottom right direction.

 

Have you verified in PS?

[stayinwonderland]

yeah, the shadows are pure black when touching the plane. They're not if they're landing on anything other than it e.g. the grass.

 

It's frustrating because it's been part of a long project and i've just been hacking it/airbrushing it. But I'm just thinking, surely there has to be a better way of doing this and surely it's simple!

Edited May 17, 2016 by stayinwonderland