Export EXR with alpha channel

Hi, I’m importing some simple EXR footage (RGB half no compression). I do my rotoscoping and then I’d like to export my shape data into the alpha channel of a new EXR that should also contain the footage.

Is that possible with Mocha Pro?

We export the rendered matte data separately, so to combine them into the alpha of the existing EXR file, you would need to do this externally to Mocha Pro.