[Bf-committers] Is alpha within Blender totally broken?

[Reuben Martin]

On Saturday, July 16, 2011 02:37:57 PM Troy Sobotka wrote:
> So far, I've been experimenting with several files and uptake tools
> using Blender in conjunction with Nuke. I have yet to be able to find
> a pattern that delivers proper alpha channels.Perhaps someone here can
> shed some light on the matter.

I can't speak for Nuke, but if blender has a bug concerning alpha channels when rendering, then it also has the same bug in the compositer, because I've never had issues keying anything.

The first two images look like what happens when trying to key a pre-multiplied image with a white background that isn't properly removing the matte. The second two look like trying to 
key with the matte being removed, but not useing linear color space blending in the compositing. But I don't know what your actual settings are.

Straight-keyed Alpha, CM on, rendered to Half-Exr, Composited with CM on. (in blender) http://img692.imageshack.us/img692/779/compositescreencap.png

-Reuben