Is it possible to "update" parts of a multilayer exr while retaining other render layers?
Let's say I have two layers A and B. I render both layers to the same exr and later I decide to re-render layer B (with option "Only render the active layer" checked). When I click on "Animate", Blender overwrites all existing exr files, so layer A is lost. I don't want to re-render all layers, since it's pretty time-consuming.
Do I have to use multiple exr files - one for each layer - to fix this? What's the benefit of the multilayer exr then?