Noise reflection in mirror

[sona]

Hi,
pls need some advice. Issue is with the glass reflection in mirror. There isn't any noise added in the glass or mirror materials. Caustic is turned off. Tried with portal and also without.
Noise appears in the mirror when I turn on the glass partition and disappear when its off.
Any probable causes?
THX

[romullus]

Does your mirror material has slightly matte material, like glossiness - 0.99? Can you set it to 1.0 and see if that solves the issue?

[GeorgeK]

can you please share your material setup of the frosted glass and the mirror?

by glass partition you meant dispersion?

[sona]

Material setup is as simle as I could make it. Only added AO to mirror for better corner visibility. But tha does not affect the noise reflection.
Plus by glass partition I meant the physical glass wall dividing shower and the rest of the room :-).

[GeorgeK]

Material setup is as simle as I could make it. Only added AO to mirror for better corner visibility. But tha does not affect the noise reflection.
Plus by glass partition I meant the physical glass wall dividing shower and the rest of the room :-).

Thanks for the images, great actually everything seems in order. Some things to consider

• For starters, did you render with IR these images or production rendering? Also are you using NVIDIA AI denoiser (if it's production render)? If yes, try removing denoising altogether.

• Secondly, please try and alter your UHD Precision to 10,0+, see if the issue persists (consider saving the UHD cache into a file, so that you'll avoid the precalculations). Try ticking the Animation/Flicker free option for your UHD cache without altering your precision values (this should remove the artifacts).

• Alternatively use pathtracing / pathtracing and again see if the issue is still there (it will solve your issue but impact your rendertimes). After considering the above please tell me if the issue persists.

[romullus]

Could you provide screenshot of the mirror material as well? Your glass materials has some issues, but that shouldn't contribute to splotchiness. I suspect the mirror, but we need to see how it is set up.

[arqrenderz]

Use uhd cache, but change from still (fast) to animation, it works for me all the time to solve those splotches

[sona]

- issue is in IR and also in production rendering
- used corona high quality denoising - turned it off - result is the same
- changed UHD Precision - it made rendering slower and the artifacts smaller
- ticking the Animation/Flicker free option - it worked (thank you Corona_GK and arqrenderz)

In attachment is the mirror material. Just to see if the culprit was the mirror.
Otherwise the issue can be considered as solved :-).

[romullus]

Nope, mirror seems fine, except... why it has refraction enabled?