Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: inatosema on 2014-11-12, 17:55:25

Title: Corona Specular Highlight Flicker / Jitter
Post by: inatosema on 2014-11-12, 17:55:25

Hi, I have a problem with the corona renderer for animation.  When I'm trying to render a metallic object with a specular highlight, The specular highlight is flickering / jittery.... dont know how to fix this. It seems like an anti-aliasing issue.  Any ideas?

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: Juraj on 2014-11-12, 18:04:21

Seems like you have extremely anisotrophic metal shader, which are by nature super hard to sample, esp. when they reflect super small light source, such as CoronaSun.
That is sort of issue right now.

Change your sampling priority towards AA (less GI), make the lightsource slightly bigger,etc..

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: inatosema on 2014-11-19, 08:22:32

Thanks Juraj,

It seems to happen even with HDRI and on reflection / refraction areas... even on glass...

Here is another scene with the same problem I'm having.

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: maru on 2014-11-19, 09:30:14

You can disable sun's visibility in reflections or tune the material of the leaves (lower reflectivity, lower glossiness).

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: inatosema on 2014-11-19, 10:13:20

@ Maru

I'm using only HDRI. No sun.

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: maru on 2014-11-19, 17:07:43

Hmm... then apart from changing leaves material you can edit the hdr and remove/soften the sun and use it as reflection override. But that's only if you are ok with such faking. Otherwise I think it's an effect that happens in real life if leaves are so reflective.

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: inatosema on 2014-11-20, 07:05:10

okay. lemme try and see what i get.

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: Ivan Snake on 2020-11-01, 15:49:37

Hello, have you found the solution to the problem?

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: maru on 2020-11-02, 15:23:35

This thread is 6 years old. ;)

But there are some solutions to this, for example:

1) https://coronarenderer.freshdesk.com/support/solutions/articles/5000529356

or if you don't need 32-bit output with high dynamic range:
2) https://coronarenderer.freshdesk.com/support/solutions/articles/12000006462

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: Ivan Snake on 2020-11-02, 23:37:38

It's all good, I found the solution.

Title: Re: Corona Specular Highlight Flicker / Jitter
Post by: ihabkal on 2021-02-10, 06:11:33

what was it please?