This scene seems to be illuminated by:
- various glowing objects
- reflective caustics from mirror-like objects, including
the ceiling I would use default render settings (just reset everything to defaults) and:
- Use an override material to paint everything with a flat gray material - this will show you how the scene reacts to lighting -
https://support.chaos.com/hc/en-us/articles/4528531820177- If your scene comes out black, this means that all lighting comes from some kind of light-emitting materials. This may not be optional, so either add Corona Lights where you need them, or exclude objects with light-emitting materials from your material override and check again.
- If you see a lot of noise from your light-emitting materials, that probably means that they are configured incorrectly. They may be using self-illumination instead of light-emission -
https://support.chaos.com/hc/en-us/articles/4528322665745- Another idea would be to disable light-emission for all your light-emitting materials and use Corona Lights instead. In that case, the lighting won't be 100% accurate, but it should render much faster.
- Once you are pretty sure that everything is fine with your scene lighting, disable the clay material override and check how the scene renders.
- It is possible that it will be still noisy. In that case, I would bet on the mirror-like objects. A possible fix is using the Rayswitch Material to tell GI rays that those materials are not reflective at all - this will eliminate any noise coming from reflected light:
https://docs.chaos.com/display/CRMAX/Corona+Rayswitch+Materialhttps://docs.chaos.com/display/CRMAX/Corona+Rayswitch+MapYou could also try adjusting some render settings to make the rendering less realistic but faster (for example by lowering the Max Sample Intensity value), but if the scene is set up incorrectly, this will most likely just make it render even less correctly.