Black fringe on render elements with render mask

[PowerCreative]

Hey all,

We aren't sure if this is a limitation for Vray or if we're doing something wrong, but we've started to use Render Mask for patch renders... what an amazing feature! But we encountered a problem - objects that were rendered with render mask have a black fringe/outline around them in all render elements. RGB Color pass looks great, but the render elements create an outline around the objects. Is this a known issue? Render settings have not changed, we're just changing out materials on render mask rendered objects. We can reproduce this across multiple machines. Let me know if any more info is needed - Thanks in advance!

[JulianT_CD]

I ran into that same issue. Seems like you can't avoid it to a certain extent. Have a look at my thread:

http://forums.chaosgroup.com/showthr...ts-Composition

and in particular this post:

http://forums.chaosgroup.com/showthr...435#post692435

If you work with Photoshop, you'll need to work with Clipping Masks for composing render elements to reduce fringing. You might also need to run "Remove Black Matte" or if all else fails "Defringe" on the merged render elements comp. That should help a great deal, but doesn't work in every case.

[Mokiki]

I think you're describing something very similar to an issue I had some time ago: http://forums.chaosgroup.com/showthr...-unclean-edges

the workaround was to disable "show calc phase" for the light cache