Transparent Opacity, Zdepth, Alpha...

[thieuma]

Hi,

I've a very junior question... sorry if it had ever been answered in another post , I searched but i didn't find... This is my problem :

I've create a background ramp and a plane which i applied a VrayMtl with a checker on the opacity slot (nopt using refraction, only opacity...). When i render it (top image) i can see two parts of the plane are transparents, and that's what i want !! but when i render the Zdepth pass in the render element (second img) it give me a whole entire plane without transparent zone.

I need to use this kind of plane with black-white opacity information with the 3dsmax atmospheric fog and the problem is the same... What can i do to make fog/Zdepth use th opacity map as alpha, and not the shape of the object ?

Thank you

[RErender]

There's no way to do it directly

There are a few ways to work around it, you can render fog and Z passes with Scanline, not really an option though if your using the Physcam dof or distortion. Another possibilty is to use displacement as a "clip map".

[thieuma]

Thank you,
I did a render of my scene whith only black light objects + the white fog + my Vray Motion blur and it works perfectly, I get what i want with your solution !!!

Thank you again !!