Hi, when reflection/refraction override(black/gray/white color or tonemapped jpeg) in scene settings is enabled, masive noise is apearing using corona 6/7 latest daily. Corona 5 without issue.
Noise is visible in Direct render element, Indirect is very clean. Increasing LSM has almost no affect.
I am using only corona sky(Hosek Wilkie) in scene environment as a light source.
Tested 32s render, adaptivity off, UHD cache, GIvsAA 4, LSM 4, MSI 4, High.clamp 0, adapt. light off, random sampler new improved. Corona5 with portals, for corona6/7 no portals and env.sampler changed to adaptive.
Renders in corona 7 identical with 6.
Scene in attachment.
Any workaround? Similar issue mentioned @cecofuli in this topic
https://forum.corona-renderer.com/index.php?topic=27953.msg170860#msg170860THX.