Greetings!
I find Lumen is amazing for outdoor but not so much for indoor or dark. Is it possible to disable its effects with a Post Process volume or box/cube, or is its effects entirely global?
I find that it can become VERY noisy on metallic surfaces, and over reflective, bouncing everywhere.
You can try placing a separate PostProcessVolume inside your interiors, and adjusting its bounds to match the size of your interior properly. From the details of the Post Process Volume you can then override Lumen and use Screen Space, Ray Tracing or a separate plugin. Not sure if it will work if there is a global (unbound) post process volume. Although you can fiddle with its priority to see if it works
You can control it via the PPV, but it’ll be a challenge to hide the transition from lumen to non-lumen. Because it manages occlusion as well as GI, you’re going to have to contend with light-leaking as well as the lack of bounce, so you’d need an area well-lit with direct lighting to the point where the switch wouldn’t be noticed.
However, I might just tinker with the reflections more. If you can stand a loss of detail in reflections, try the command ‘r.Lumen.Reflections.ScreenSpaceReconstruction.TonemapStrength’. It should remove your major noise, but it’ll seriously crunch away detail.