Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: valwizard on 2015-02-11, 15:52:28

Title: noise in the reflection pass
Post by: valwizard on 2015-02-11, 15:52:28
Hello everyone,

I am trying to get an internal animation done with corona and Corona is showing the great results, I only have a big issue with trying to eliminate the noise from the reflections. Any help I will really appreciate. Also any help with the best render settings for animation flickering free would be really appreciated. Thanks a lot!
Title: Re: noise in the reflection pass
Post by: johan belmans on 2015-02-11, 16:00:37
I guess you are using round corners as a material option.
If you model thouse round corners, you won't have the problem.
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 16:03:35
there is no round corners on materials
btw thanks for so quick reply
Title: Re: noise in the reflection pass
Post by: maru on 2015-02-11, 16:44:52
A better screenshot/render would help because we have no idea what we're looking at. :)

I would guess these are reflective caustics. If so, you can completely disable reflective caustics or weaken them using rayswitch material/map.

See the examples at the bottom:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000529341
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 16:57:15
Thanks for helping I will try to use rayswitch material and eliminate the possibility of caustics involved and will have a new screen attached
 
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 17:51:38
All flakes remains in place still too noisy and gold become clay. Seems the rayswitch material is not an option.
Title: Re: noise in the reflection pass
Post by: maru on 2015-02-11, 18:16:30
Maybe more antialiasing is required? The images you are showing - after how many passes and how much time per frame is this?
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 19:06:44
My settings was 36/2 10 passes 15 minutes on i7 3770k for the HD resolution   The reason behind is that I got a very fast reasonable clean pass in the lighting and GI but reflection is a nightmare. I am rising it to 20 passes and even to 50 to see the result but even from 50 passes I got  reflection noisy which cause an animation flickering. See attached. I am sorry to not post the entire shot only fragments because we are under non disclosure agreement.
Title: Re: noise in the reflection pass
Post by: Fibonacci on 2015-02-11, 19:22:59
Hi,

today I got a nice light passes, but the beauty was so noisy in the steeinless metal. The solution was lower bump (0,002 ) and a bit "grayer" bump and light map in the materials setups. That solved my problem.

Maybe that's help for you too.
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 19:33:21
light map in the materials setups. What that means? having light map in the gold shader? I got a corona normal tex in the bump slot but on the door I only have a yellow reflection and no diffuse and no bump at all.
Title: Re: noise in the reflection pass
Post by: maru on 2015-02-11, 19:47:16
My settings was 36/2 10 passes 15 minutes on i7 3770k for the HD resolution   The reason behind is that I got a very fast reasonable clean pass in the lighting and GI but reflection is a nightmare. I am rising it to 20 passes and even to 50 to see the result but even from 50 passes I got  reflection noisy which cause an animation flickering. See attached. I am sorry to not post the entire shot only fragments because we are under non disclosure agreement.
If you get good quality light/gi after 20 passes and bad reflections, then why did you raise gi samples to 36? Try with lower gi samples (you can even go down to 8 or so just to check) and see if the gi quality will be good enough after more passes.
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 20:04:51
I am trying to understand what I am doing and the logic behind is  that the reflection noise is more part of gi then the lighting, also is the material. I eliminate the bump and any possible noise generators from that so rising gi should help eliminating noise caused by insufficient samples for  the cornices. Or this is an " AA " noise? I will have another sample with lower samples but then I should rise LSM to kinda 8 to balance insufficient light samples, shouldn't I?
Title: Re: noise in the reflection pass
Post by: maru on 2015-02-11, 21:07:43
I am not sure what is causing noise in your scene.

About sampling/time/passes/quality, maybe this will help:
https://coronarenderer.freshdesk.com/solution/articles/5000518064-how-many-passes-is-enough-

So basically it may be worth checking if you need many gi samples * little passes or little gi samples * many passes.
Title: Re: noise in the reflection pass
Post by: Fibonacci on 2015-02-11, 21:36:30
" light map in the materials setups. What that means? having light map in the gold shader? I got a corona normal tex in the bump slot but on the door I only have a yellow reflection and no diffuse and no bump at all."

Sorry for that, it was a wrong phrasing...I don't know why I wrote "light", but..anyway...I meant if you use any bitmap in the reflection and glossines slot.
Title: Re: noise in the reflection pass
Post by: Fibonacci on 2015-02-11, 21:50:51
Hows about the albedo pass? Is there any red colored ?

? Did you tried to build up ( lower values to higher values )the reflection in the material  ?  Darker value in the reflection slot ( the color brightness under 200 value ) with lower glossinsess ?

If the render setup not solving the problem, than you have to search in the material setup. I think.
Title: Re: noise in the reflection pass
Post by: valwizard on 2015-02-11, 23:47:10
Thanks a lot  The Albedo pass is black and white not even pink I  used to use 8/2 150 passes 1 hour 15 min reflection are a bit better but the gi is messing the picture. 16/4 30 min 58 passes not bad but still needs playing It is always about balance but the problem is I kinda not understand the ink between settings instead of vray and how they work together - the principle behind this how corona works. In vray is simple - once you understand how DMC and AA works together there is only one problem - computer power. I am trying to understand the fundamentals of Corona. Still a way to play but I got rid of the nasty flakes - here is the last result 20/4 30 min 47 passes