Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Giona on 2019-02-05, 09:43:48

Title: GI problem behind glass?
Post by: Giona on 2019-02-05, 09:43:48

Hi all!
I encountered a strange problem while rendering an interior scene.
It looks like the GI has some problem when seen from behind a glass element.
The image attached is self explanatory.

If you look at the ceiling, on the righ side there is a glass door and the GI looks really bad.
While in the center of the image, the door is opened and the GI seems good.

Is it a know limitation of UHD cache? Any trick to solve the issue?
I'm going to try a rayswitch material for the glass door, leaving the GI slow empty..

Corona 3 HF1, Path tracing+Uhd cache with standard settings.

Let me know if you have any suggestions!

Thanks

Title: Re: GI problem behind glass?
Post by: sprayer on 2019-02-05, 12:23:27

Are  you open old corona scene? Try to change Precision in UHD cache settings

Title: Re: GI problem behind glass?
Post by: Giona on 2019-02-05, 12:44:20

Quote from: sprayer on 2019-02-05, 12:23:27

Are  you open old corona scene? Try to change Precision in UHD cache settings

I'll try to rise the precision. At the moment is at the default 1,0.

Title: Re: GI problem behind glass?
Post by: TomG on 2019-02-05, 14:24:03

Is the new NVIDIA denoiser used, and if so, does disabling it make any difference? If the glass is just turned off (made invisible), does it make any difference?

Title: Re: GI problem behind glass?
Post by: Giona on 2019-02-05, 15:07:11

Quote from: TomG on 2019-02-05, 14:24:03

Is the new NVIDIA denoiser used, and if so, does disabling it make any difference? If the glass is just turned off (made invisible), does it make any difference?

Hi Tom, the nvidia denoiser was already disabled (both production and interactive). If I remove the glass in front of the camera, the problem in GI disappear.

Title: Re: GI problem behind glass?
Post by: maru on 2019-02-05, 15:45:46

That's very strange, I don't recall any similar issues.
I only remember something about glossy refractions, and objects visible in the mirror.

What we see in your renders is seen directly, or is it a reflection in some kind of mirror object?
Sending the scene over to us would be probably the best idea.