Rendering with alpha

Support Basics & Interface
#1

Im trying to composite an image in a separate package but I can’t seem to find any way of rendering with an alpha channel. Is there anyway to do this or am I going to have to render out masks for each frame?
Any and all advice much appreciated.

#2

In F10, set it to RGBA and use Premul or Key instead of Sky.

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#3

thanks very much.