Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: sbrusse on 2014-07-18, 01:36:10

Title: Get rid of fireflies and smooth out glossy reflection
Post by: sbrusse on 2014-07-18, 01:36:10

Hi guys,

Hope you are all doing well.

I've got a little personal animation project I'm working on here and I can't get rid of fireflies and getting glossy reflection smooth.
Just out of interest, I'm posting the same render done in VRay where I don't have this issue.

Corona :
(https://dl.dropboxusercontent.com/u/368267/corona.jpg)

Vray :
(https://dl.dropboxusercontent.com/u/368267/vray.jpg)

As you can notice, The whole image is noiseless and only my ground plane is getting fireflies.
This is way more obvious with the images in full ress, not sure why the forum scales down the previews.
Is there any way to fix this? My render sits there for a hour already but beside the ground plane, the render would have been done in 20 minutes, tops.

For those who want to know, as a comparison, VRay 3's image took 2h to render, and it contains way more noise, everywhere, beside on the ground plane ;-)
Any hints ?

Cheers

Stan

Title: Re: Get rid of fireflies and smooth out glossy reflection
Post by: JoeVallard on 2014-07-18, 04:40:52

I had a couple scenes were the bump map was causing fireflies in glossy areas. So if it has a bump turn it off and section render.
Have you rendered with a standard Corona Material in the override slot? This could tell you if its in the material or lighting.

Title: Re: Get rid of fireflies and smooth out glossy reflection
Post by: sbrusse on 2014-07-18, 11:53:38

All right,
I will try that.

Thanks

I'll keep you posted.

For your information, here it is been rendering close to 12h there are still a few fireflies on the left.

(https://dl.dropboxusercontent.com/u/368267/corona_12h.jpg)

Title: Re: Get rid of fireflies and smooth out glossy reflection
Post by: sbrusse on 2014-07-18, 12:28:15

All right, so I did the override and everything is super clean so it's not the model.

If I take the bump out then so fireflies at all.
So I took the bump back on but had to blur the map to the initial blur of 1.0, I had it at 0.01.

It changes the look quite a lot, and I don't really like the look and feel of that blurred bump.
But after 20 minutes it's nearly ok :

(https://dl.dropboxusercontent.com/u/368267/corona_BlurBump.jpg)

Any other way to fix this?

Cheers

Title: Re: Get rid of fireflies and smooth out glossy reflection
Post by: JoeVallard on 2014-07-18, 18:24:50

A bump map has to have some sort of filtering or blurring. Set filtering to None and try lowering the blurring down incremental, until you see the fireflies.