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Old 08-29-2013, 10:18 PM   #16
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Tim Jones
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Playa Del Rey, USA
Join Date: Mar 2002
Posts: 210
I took a look at your scene. Its a common problem of using raw passes. In fact any pass that you multiply can cause similar problems.

Inside of vray when a frame is rendering its doing all of these calculations before anti-aliasing is applied. However, if your trying to composite these buffers together your doing the math after the anti-aliasing. So edge issues are common.

There is a work around that fixes this and from what I've heard its likely to be built into Vray to correct this problem sometime in the future. In order to remove the changes in pixel color from the AA you must create a raw pass using for example the diffuse and lighting pass. You would use a "divide" blend mode which will remove all of the diffuse color and leave you with a rawLight pass. The difference is that with this newly created rawLight pass the AA has been compensated for. Make your color corrections to this new rawLight pass before multiplying it over your diffuse again. The end result is a pixel perfect beauty pass that will match exactly what you rendered from Vray. Anytime your planning to make use of a raw pass of any kind. You should use this technique to create it in comp instead of using raw pass straight from Vray.

I posted about this same issue several years back on my blog. There is a link from my blog to another forum that had a good example of this same problem.

Tim J
Old 08-31-2013, 07:09 PM   #17
New York, US
Join Date: Jul 2012
Posts: 32
By the way, I haven't tested it yet, but I think if you render out a multimatte element for the box's facets then you can just assemble the passes, precomp them, duplicate the precomp, and use that multimatte element as a track matte for each copy of the precomp. That way everything would stay within corresponding facet.

Last edited by X-RUST : 08-31-2013 at 07:16 PM.
Old 09-03-2013, 01:36 AM   #18
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Join Date: Aug 2013
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Thank you both Seraph and X-rust for your valuable time! I'm going to explore both of these options immediately.
Old 09-03-2013, 01:37 AM   #19
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