Is it possible to BPR render a scene and have the background be an alpha channel rather than colored or an image? If that is possbile how do I do that? Thanks in advance
Set background color to black, do your bpr, grab doc and export as .psd, then you can easily take out the black for the alpha.
i believe the render passes has an alpha stored in it when you render.
Not directly with the alpha as a channel in the PSD file. But when you use BPR you have your mask pass stored in the Render>BPR RenderPass. Just click on it and save your alpha. Also i suggest you to play with all the other passes and compo in PS.
Hope this helps