So i gave this a try, thinking…it can’t be that hard right?
First off, i exported a series of shots, same idea … put a power window on it, add an alpha output node and export.
Right away i’m wondering “just because the power window is there, does that create an alpha output, or do we need to do some other song and dance?”
I exported a dnxhq, dnx444, dpxrbg, tiff16bits, uncompressed argb, uncompressed bgra, and an uncompressed quicktime.
Brought each of those into fusion, turn my viewer to alpha, and each showed full screen white, no power window key.
I then brought each back into Resolve, and under clip settings, set each to have an alpha channel. The dnxhq, tiff16bits and uncompressed each came in as a keyable element, the others did not.
I then brought each into after effects. Of all those files, only the uncompressed bgra file gave me the option of assigning an alpha component, but it, nor any of the others, showed up as a keyable element.
So although it appears some files will export an alpha channel, they are only visable when brought back into Resolve. I’m sure there is a reason you might want to do this workflow….just not quite sure what it is, perhaps archiving elements for future use, but certainly not what most of us would think of as an alpha output workflow.
Glenn