Emissive lighting needs to be stored in the surface cache to appear offscreen, which requires precomputing card positions when the mesh is imported. Skeletal meshes can’t do this because they animate, and so they don’t have surface cache, so any emissive lighting from them will never be visible when the mesh is off screen.
Isn’t really a good way to fix this currently, a very convoluted way would be to attach static meshes to a socket on the legs, set them to hidden in game + affect indirect lighting when hidden.
The Lumen team has said they’re looking into alternative ways of generating surface cache that don’t rely on capturing from precomputed positions so this might be fixed in the distant future.
Depends on what you mean but that. Lumen gathers samples over multiple frames so there will always be some noise before it converges when surfaces are disoccluded.
Lumens surface cache is also updated on a budget, which doesn’t apply here because your emissives are skeletal meshes which don’t generate surface cache. But the way to speed the surface cache up, is to increase the lumen scene update speed in the post process volume.