Matte object shadow catcher vs VRaySun clouds

[eiler_wessel]

Hi,

I wonder, can one not use Vraysun clouds without seeing matte objects in alpha channel?

If I switch off clouds in VRaySun, the matte object disappears, but if I use the clouds, the matte object is partially visible in alpha. What am I doing wrong?
Doesnt matter if I have reflections on matte object material or not, or if I use the MtlWrapper matte object alternative.

[vladimir_krastev]

Hi thanks for contacting us. Is this the setup you are describing?

The plane beneath the teapot is set to matte with Alpha contribution set to -1.

[eiler_wessel]

Hi thanks for contacting us. Is this the setup you are describing?

The plane beneath the teapot is set to matte with Alpha contribution set to -1.

Hi, thanks for the swift reply.
Yes, that is what I get as well.

The VraySun cloud function is quite handy for my scenes, but I do want to have only shadows show on alpha

[vladimir_krastev]

Hi, the issue is reported under VMAX-12861 in our bug tracking system.

[Joelaff]

What if you made a duplicate VRaySun with clouds off and have that one affect the ground, while the normal VRaySun (with clouds ON) affects everything except the ground?

I assume this has something to do with the ground shadows work, and the clouds casting a shadow everywhere to some degree when Ground Shadows are OFF. Perhaps try turning Ground Shadows ON to see if this helps.

[vladimir_krastev]

You will end up with an object that is in the shadow of the clouds and the plane is not or the other way around. Whenever you have a shadow from the clouds over your matte, the alpha won't work correctly