Quote - I'm obviously not up to date on my Vue skills. You say you render against a black background.  Do you create the background in Vue?  Then you hide everything but the one object you want to render including the background you made and this gives you the object with a built in Alpha channel for each frame?

I create the whole scene in Vue.  I have a background (sky, mountains, clouds, etc) that I render by itself once.  Then I use a black backdrop when I render individual objects (planes flying, etc), but Vue is still using the background sky for lighting those objects.

If I tell Vue to not produce an alpha for the ground plane (even if I unhide the ground plane), Vue will render the ground plane but the PNG render will not show it.  This allows me to use the ground to bounce any light from the sky.  I'll replace the ground with something else usually.

A super computer with lots of RAM could just render everything at once and not bother with video tracks.

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