Render Pass with Alpha?

Is it possible to make the render passes use an alpha background instead of solid black? I want to grab the color info for each material, and not have to remove the black in Photoshop everytime.

Check transparent under the Film tab in the render panel.

That is not what I’m looking for, unfortunately.

Here, you can see I already have that selected for Freestyle rendering, but I’m also trying to get diffuse and glossy color passes on a different Render Layer. My other option is to make all current materials emissive, and that would be tedious just to change them back.

Oh, sorry, I misunderstood the question. Unfortunately I don’t know the answer to what you’re looking for, but I hope you get it resolved soon!

No worries, I appreaciate the resonse!

Not directly with a toggle. The passes are components which get added and multiplied that makes the final result, so they don’t need alpha. You could setup the compositor to use the alpha of the image, or set nodes to set the alpha based on a color, and use file output node to save it.

Thanks for the info, and great idea, thank you!