I am currently facing a little problem. I built up a scene in Unreal and wanted to do some compositing in Fusion or Photoshop afterwards. So, in the path tracer set-up, I added additional render passes just as “Specular”, “Roughness”, “SceneDepth” etc. However, I cannot find any render pass that would allow me to extract the lighting information from Unreal. This would be crucial as I need to rebuild the beauty pass in Fusion later on in order to do the compositing step. Is there any workaround on this?
Your best bet might be to do a multi render pass with Lumen and Path Tracing. Eg, select the static meshes you absolutely need to be rendered with path tracing, say the immediate foreground items, table, etc as a stencil layer. There’s a bug in UE 5.3 for Stencil Layers by the way for path traced rendering so you’ll need to add “R.Nanite” with the value set to 0 if the static meshes selected contain Nanite. Then render the rest of the scene with the added render passes (quite a few more addiitonal ones) via lumen and then composite both layer together in post via Fusion, etc. In terms of specific console variables for light,I’m not sure, but there is a really good plugin for assisting with getting the best possible lighting extracted from the scene, called 'Light Forge". Here’s a YT video on it https://youtu.be/dZmnDDSNUEY?si=ZI7kGSQaTWw_y2j5
