noise on lights switched off in lightmix

[Bzuco]

Hi,

I was reading somewhere on this forum/freshdesk, that some noise can ocure if I switch some light off in lightmix...or that lights are stealing samples....
Examples in attachment.

Q1: why I got better result on light switched off in interactive rendering than in normal production rendering? I switched force path tracing off so it should be the same settings as production render with HD cache...

Q2: is there some workaround how to use lightmix when I want to make several night renders with light variations ON/OFF without noise? Or lightmix has some limitation and I can only change intensity and color, but set light off is not recommended?
THX

[Bzuco]

Testes also daily builds 16.aug., but same result. Increasing direct light samples did not help, corona denoising doesnt help at all.

I tried also replace all corona lights to photometric lights, then there is no noise around lights switched off in light mix, BUT whole render is 100x slower :\...so how to make several night renders(light variations ON/OFF) from just one render using lightmix?

[maru]

LightMix sometimes can be used to do day > night renders, but if there are some problems with that, then we cannot do anything about it. Generally it is intended for more subtle changes in light intensity and color.

You are getting different results with IR and regular render, because IR is using slightly different render settings. Most probably you simply got more passes faster with IR, and less passes with regular render, that's why the overall quality is better, but the problematic areas are even worse.