I have noticed this issue after installing Corona 4 Release version, when i create simple metal (or mirror-like) material with ior 23-999 and glossiness between 0.7-0.99, rendering models with material applied becomes weird and slow, its happens both for IR and Production rendering in all complex scenes no matter of lighting, with hdri or simple Coronalights, caustics on and off, with new lightsolver on/off, the only thing that helped me is a fresh scene with one sphere in it) then it is rendered well.
I attach screenshots of comparison between the 5th and 25th pass
I want to upload GIF but it is too big)
This definitely doesn’t look correct, but we will need more details to understand it (for example - how exactly is the bg/enviro loaded?)
Could you send a sample scene here or contact us about this at https://coronarenderer.freshdesk.com/support/tickets/new ?
Thanks a lot!
I’ve deleted all objects except one with materials causing this bug, metal with glossy ~ 0.90 and glass with refr glossy ~0.95
enviro hdri loaded as CoronaBitmap in “Single map” slot in scene settings but it is the same for multiple maps connected to LightMix and for maps in 3ds max environment tab
