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berniebernie
08-14-2009, 04:59 PM
Okay, I've had trouble in the past with premultiplication. I though it was great as I had full RGB and clean alpha. I had some problems with SSS and premultiplication during the year, posted here, and got warnings from Djx/masterzap if I remember, but did not listen.

Here's my problem (the spots in all my passes);

http://mlkdesign.online.fr/dump/premultiplied_horror.jpg
(simple mia+fg on 2009)

Is it generally a bad idea to use premultiplication then, and why is it there?

Why do these spots appear ? (I've fiddled with clipping/buffer properties to no avail)

Thank you for your input.

Bernie
ndeboar
08-17-2009, 04:54 PM
Although this doesnt look great here, how does it look once you've multiplied your alpha in comp?

If you do a mult div in comp with the pre-multed image, does it look like your rendered version?
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