Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] General Discussion => Topic started by: fa2020 on 2017-05-05, 16:31:48

Title: How to render a noise-free image?
Post by: fa2020 on 2017-05-05, 16:31:48

hi guys,
I have modeled a rim and I want to render it using Corona 1.6.
Because of metallic nature of the material rendering takes too long to clean up all the noises. I chose a small region to test how long it takes and I saw that that small region took about 1700 passes to clean up (Of course not completely). I used KeyShot and got this result you see as attachment.
How can I render such a sharp image using Corona 1.6? Using Denoiser removes some important small details too.

Title: Re: How to render a noise-free image?
Post by: Tanakov on 2017-05-05, 16:36:34

Have you tryed using denoiser?

Title: Re: How to render a noise-free image?
Post by: fa2020 on 2017-05-05, 16:38:02

Quote from: Tanakov on 2017-05-05, 16:36:34

Have you tryed using denoiser?

Using Denoiser removes some important small details too.

Title: Re: How to render a noise-free image?
Post by: Tanakov on 2017-05-05, 17:46:07

Have you tred to tweak its radius?

Title: Re: How to render a noise-free image?
Post by: maru on 2017-05-05, 21:31:41

The attached image is from Keyshot or Corona? I would say it looks noisy.

If the noise is caused by glossy reflections, I would suggest turning up GIvsAA - to 32-64, but probably not more.

If the noise is caused by small details such as bump maps, scratch maps, I would suggest turning down GIvsAA - to 8-4, but not less.

Title: Re: How to render a noise-free image?
Post by: fa2020 on 2017-05-06, 16:00:07

Quote from: maru on 2017-05-05, 21:31:41

The attached image is from Keyshot or Corona? I would say it looks noisy.

If the noise is caused by glossy reflections, I would suggest turning up GIvsAA - to 32-64, but probably not more.

If the noise is caused by small details such as bump maps, scratch maps, I would suggest turning down GIvsAA - to 8-4, but not less.

The image belongs to Keyshot. I asked them to help me about how to render a photo-realistic image. I provided them my OBJ file which I made using Rhino. Please download it and see if you can come to a noise-free and photo-realistic final image.
https://www.keyshot.com/forum/index.php?action=dlattach;topic=14710.0;attach=43344

Title: Re: How to render a noise-free image?
Post by: LukaK on 2017-05-06, 18:11:52

I don't see much problems with noise even with slight bump texture as scratches (Sieger one) and a bit of anisotropic reflections.
I let it render for approx. 50 passes on not really fast computer  (I7 5820K).
First render is without noise reduction, the second one has 0,3 noise reduction. If I'd go higher with noise  reduction, then the smallest scratches start to disappear of course.
Default settings.

Title: Re: How to render a noise-free image?
Post by: sprayer on 2017-05-07, 11:50:09

(http://funkyimg.com/i/2sJh8.jpg)
25passes, 0.4 denoise

Title: Re: How to render a noise-free image?
Post by: fa2020 on 2017-05-09, 13:45:04

Thank you guys. It was helpful.