exporting avi with alpha channel

[madteo]

hey im trying to export animation footage and when I export it at RGBA to an avi, it seems like its saving the alpha channel but when I bring it into after effects the layers arent alpha'ed and theres this weird black shape where the alpha should be. any ideas why this is happening?

[slowtiger]

RGBA just tells TVP to render an alpha channel.
AVI is just the file format.
You also need to choose the correct codec which preserves the alpha channel. I'd recommend PNG with millions+ colours.

[Paul Fierlinger]

Have you configured the AVI to Uncompressed (BGR32) first? Only then should you select the RGBA 32 bits mode, usually as PreMultiplied.