Matte Object with Shadows

[guenther Malek]

I am trying to create a Matte Object that is recieving Shadows.

 

On the left side you can see my starting point,

then i "VrayMtlWrap" my floor material and set up the Matte settings.

(i can also use the "Make VRay shadow catcher" button instead, the result is the same)

 

The Alpha looks correct, but why is my plane pitch black?

Is there something wrong with my settings?

 

i can rebuild my picture in Photoshop, but shouldn´t I see the same

result in my VFB?

 

 

VRay Help says: "...This means that the object will not be directly visible in the scene; instead, the background color will be shown in its place...."

 

This means, i should see my background image instead of black.

 

Please help!

[Tom Bussey]

The plane is black because it's rendering as a matte surface (see through) and your background (environment) is presumably black or invisible. FWIW, that's exactly how I'd do it, the black background captures by the shadow alpha then becomes your shadow in photoshop when overlayed on the background. (not entirely sure if this is exactly the correct process, you might need to employ some kind of blending mode for the shadow strictly speaking)

 

If you want just a flat image in the frame buffer, you're going to have to use a different method, for example a mesh that fills that view with the background texture set as 'screen' applied to it, or add a 'background image' in the frame buffer and save out some format without an alpha like jpg or tif (I think you may need to do this 'manually' after it's rendered).