View Full Version : problems w/ afterFX compositing

03 March 2003, 11:03 AM

I'm rendering a character firing a gun into the air. I am using keyframed spotlights to simulate the muzzle flash, w/ a Solid Fractal mapped to the light fog/volume material attribute.

Everything looks fine against the black backdrop, but when I take it into AfterFX I get these annoying black cone things at the end of the barrels on every frame (Im guessing this is the light fog)

I've tried editing the various attributes on the the light & fog, but it seems that when I get rid of the annoying black cones, I also get rid of the muzzle flash.

I've attatched an example since I couldn't figure out how to insert an image into this thread (perhaps I was just born a crackhead)

Any help would be greatly appreciated


03 March 2003, 05:41 PM
I'm not sure but you might want to check how you're interpreting your alpha in after fx also render a frame in maya and switch to your alpha channel and see what it looks like. :shrug:

03 March 2003, 09:59 PM
yes indeed, it seems like you are using an integrated alpha channel, premultiplied with black. switching your interpretation method should fix it! :p

03 March 2003, 10:51 AM
you have to premultiply it with either white or black, whichever suits your needs, that will get rid of it

03 March 2003, 11:05 AM
I also met this problem. It's very difficult to work with pfx and fog.
You can try to get a result in compositing and rebuild a new fog with the Zchanel.

03 March 2003, 04:43 AM
actually, I just needed to check the "use color transparency box" icon on the light. that took care of it immediately. (I'm relatively new to Maya & tend to overlook crucial details like that)

thanks for the help though guys


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