This question is probably worded poorly because I lack the compositing terminology knowledge to ask it properly, but I’m trying to render out a pass with “only lighting” without anything else in the shot exactly like the result from using the “shadow only” shadow option with Blender Internal materials but with isolated lighting instead of shadows.
This will be for compositing on top of images/video to have rendered lighting in real environments.
I didn’t find any simple option in the passes list that would give me what I was looking for in either Cycles or Blender Internal (although I might have missed it) so I tried a clumsy solution using keying nodes (with a Blender Internal render) that gives me a result close to what I’m looking for, but it is incredibly inelegant and is likely to cause problems in a lot of situations, so I’m hoping there is a better way.
Here’s what I came up with (the result in the backdrop is what I want).
There has to be a better way! Any suggestions? Thank you!