I have an interior scene that renders fine with a default gray color in the environment. It cleans up quickly. It looks much better overall if I put in an HDRI in the env spot, but it takes about 10x longer to clean up, if it even cleans up. Is there a trick to using HDRI files as a lighting source?
I tried applying it directly to a sphere and increased the samples to 200, not really any better. I switched to PMC from PT and it's better, over time, but still not nearly as quick as when I'm not lighting with HDRI. Does anybody have any advice?