Matte Shadows issues

[pmargain]

Hi,
I'm working on a project where I need to render shadows on a surface without the surface appearing in the render. I have tried setting the surface as a matte object in the V-Ray object properties and also using the VRayMtlWrapper, but I couldn't make it work — the shadows never showed up.

I replaced the surface with a V-Ray plane, and it works better, but I'm still having issues. The V-Ray plane appears in the render as a semi-transparent object, which is not ideal. I'm using V-Ray 7 and 3ds Max 2023.

Image 1 shows the render with the shadows, but the plane is visible. Image 2 shows the render without the plane. Image 3 shows my V-Ray object settings.

Please advise.
Thanks!

[kosso_olli]

In image 1, it looks like you have some additional shadow spilled on the VrayPlane, hence the dark appearance.

[hermit.crab]

To get the shadows to render, the matte object (plane) must be left visible to catch them. Note that the material applied on the Matte object affects the rendering, to avoid this, make sure you use a black Diffuse, no reflections, refractions, self-illumination, etc.