lost alpha channel

Here is an intereitng problem:

-I have rotoscoped som footage in Shake and now I have taken it in to
FCP to do some speed changes and I also to duplicated it and then reversed the second instance of the footage so that it "loops"

Funny thing is that on the reversed footage the alpha channel is gone.
Not in FCP (it is still an alpha) but when I render it out as Quicktime movie and
open it up in a 3rd application.

I thought at first it may be the fact that when I reverse the footage I ruin the alpha when I render the timeline. (The timeline needs rendering when the clip is reversed)
So I tried exporting it without rendering the timeline and the problem remains.

Anyone had this issue and solved it?



Johan Polhem
Motion Graphics
www.johanpolhem.com

Your timeline is in what codec?

DV does not have an alpha channel. You need to export in a format that does. Animation at millions plus color depth. Or - stay in DV and also export a lumma matte pass

Ian

Hi Ian.

I'm using the Animation codec.
And the funny thing is that the alpha only works on half the footage - the bit
that has not been reversed.



Johan Polhem
Motion Graphics
www.johanpolhem.com