View Full Version : alpha bleeding

08 August 2010, 03:37 PM
Is there some magical way to get alphas to look right? I know that a lot of people use dilate filters to adjust alphas but I can't understand why it's always a problem. It's really bad in my current scene (notice the black bits around comped elements):

Is this something that's still a problem for most people? I'd love to know if there was some magic way to fix it without filtering, which kills sharp corners on edges.

08 August 2010, 04:30 PM
ok - I figured it out. It was because I was also including the alpha channel in Plus merges. Once I went through and disabled all those, the black halo went away.

08 August 2010, 06:37 AM
just in case your not familiar with it:

If your working with pre-multiplied images (eg all 3d renders), you need to un-multiply the alpha before you do any color correction, and then pre-multiply after. Otherwise you'll get funky edges like this.

08 August 2010, 02:58 PM
OK - thanks.

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08 August 2010, 02:58 PM
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