Shading or Lighting discrepancy issue

So I’ve been having this problem since working in 2.8 and I don’t have a clue what could be causing this issue but I went and stripped down a project as simple as possible trying to isolate the root cause. It seems its a mesh that has an emissive material and when I disconnect the node or hide the mesh the problem disappears. It’s like if the mesh was lighting up the other mesh. Weird thing is that the mesh is inside the other mesh and its strength is super low (1). I am attaching the file.

  • Render once using slot 1.
  • Hide mesh 2 or disconnect the emissive node.
  • Render again using slot 2.
  • Toggle with J

You will see how the tone changes. This never happened to me after so many years using Blender until now already in a few projects in 2.8.

I get your issue, but my question is : why would you ever add an emissive object inside another ? :thinking: … For me it’s non sense because rays should never come from the other inner side of a face (flipped normal)

I think that only reason why you would do it, is if you are simulating an actual hollow object, with some empty space inside, and with an other object inside. In that case, the hollow object faces should have some width. Add a Solidify Modifier on your obj 1 (the one containing another) and your problem will be gone

See you :slight_smile: ++

Hey thanks for your reply. As I explained this is a stripped down version of a project for a client. That emissive mesh in reality was behind a piece of glass of a screen that was carved with a boolean object in that mesh body. It was really surprising to find out that the problem persisted even doing it like that. I dind’t move the mesh because it is where it was. I had a few more objects with emissive materials and just that one I think was causing this issue. Even if you move the mesh out the result is the same and funny thing is you get a brighter shade when that mesh is hidden. So I don’t really understand what’s going on there.