White fringe ring when compositing trees *exr

[alias_marks]

Hey Guys, I've gotta little snafu I was hoping someone might have some insight on. I'm trying to save on some render time and composite my trees as a separate layer in after effects but I keep getting this white ring around my trees no matter how I save my exr out of max. I'm using 32 bit exr's and have tried alpha & alhpa+Pre-multiplied alpha and am getting the same result.

 

Anyone know a good workflow here so that the alpha saves correctly and composites into aftereffects so it looks like the original render?

 

Thanks for taking the time to browse any any feedback,

 

Cheers

 

 

Both ways result as what's shown below.

 

 

M-

 

EDIT:

For reference here's a shot of what the raw tree render looks like, basically it looks like max is saving out a bit of the background with the tree files.. is there any way I can tell max keep the background out of the alpha channeled trees?

 

Edited July 2, 2010 by alias_marks

[Nils Norgren]

This is a classic problem, I am constantly harping on everyone here to render background black for composting. If you need your environment to affect the scene, put it in the vray override, for environment and reflection if necessary. When the background is black premultiplied or straight alpha will work properly. My preference is to use straight alpha channels.

 

Hope this helps,

 

-Nils

[alias_marks]

Great Nils, Thanks so much for the help. I'll give it a shot. Out of curiosity what advantages do you find are helpful when using straight alpha channels vs. pre-multiplied?

[Tommy L]

Have you tried a different import interpretation in Aftereffects? Straight vs premultiplied?

[alias_marks]

Have you tried a different import interpretation in Aftereffects? Straight vs premultiplied?

 

Tried this and it helped reduce the fringe by about 50% but it's still there...

 

Doing some reading and I'm understanding why straight alpha is a better option to help keep halos from appearing.

 

Thanks for the help gentlemen, much appreciated.

 

Edit:

Tried the compositing with with black background, straight alpha, and interpreted straight alpha in after effects and worked like a charm. Thanks again

Edited July 2, 2010 by alias_marks