Inconsistent / Unusable Alpha w/ Matte Objects

Can someone tell me why V-Ray still does this to me? Here’s a pass of an exterior canopy I’m rendering for an animation, however some of the building geometry runs through the ground -- it’s uneven terrain, there’s simply no better way to do it in production. So when I want these columns rendered on their own pass and terminating at the ground level, I select all my ground layer objects and in their V-Ray properties check off Matte Object and set the alpha to -1.0.

V-Ray has NEVER done this correctly for as long as I’ve been using it, and I know I’ve posted on it before. As you can see, for some ungodly reason my curbs -- even though it says in their properties when I check again that they are set to matte with no alpha -- still render in the alpha channel. Anybody know how to fix this?

Thanks guys,
Shaun

This usually applies to glass, so it’s Just a long shot Shaun, but does the material for the curbs have affect alpha checked? Sorry if this is not helping, I’ve not experienced this (or tested for) this problem…

JR

Just put affect alpha to 0…:wink:

Thanks guys -- guess the email notification isn’t working, I didn’t realize anyone had responded. I’ll try the alpha set to 0 rather than -1… I just don’t get why that works fine for the pavement, grass, paint lines, etc., but not the curbs. It’s suspect…

Shaun

Also make sure there aren’t any double faces.

Best regards,
Vlado