Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] Bug Reporting => [C4D] Resolved Bugs => Topic started by: fabio81 on 2017-02-27, 12:58:07

Title: light problem
Post by: fabio81 on 2017-02-27, 12:58:07
HI,

someone knows me explain why there are the spots on the wall?

Title: Re: light problem
Post by: maru on 2017-02-28, 17:41:12
Hi, it looks like these could be UHD Cache artifacts. You can easily check that by switching to path tracing for both GI solvers.
We don't want the UHD Cache to produce splotches, so sending a scene would greatly help too.
Title: Re: light problem
Post by: fabio81 on 2017-02-28, 17:46:01
Thank you for reply, where I can send the scene? Seem to GI errors
Title: Re: light problem
Post by: burnin on 2017-02-28, 22:23:39
Here's a quickie.

(https://s10.postimg.org/kpvk5i3o9/Light_Emission_bug.gif)
Title: Re: light problem
Post by: fabio81 on 2017-03-01, 09:46:05
Here you can see the problem with the rendered scene
Title: Re: light problem
Post by: maru on 2017-03-01, 13:53:03
Thank you for reply, where I can send the scene? Seem to GI errors
Either here: https://corona-renderer.com/upload/
Or here: https://coronarenderer.freshdesk.com/support/tickets/new
Title: Re: light problem
Post by: fabio81 on 2017-03-01, 14:09:29
Thank you for reply, where I can send the scene? Seem to GI errors
Either here: https://corona-renderer.com/upload/
Or here: https://coronarenderer.freshdesk.com/support/tickets/new


ok thanks, just sent
Title: Re: light problem
Post by: fabio81 on 2017-03-03, 09:26:10
Also here the same problem, I noticed that a lot happens when the light is diffused
Title: Re: light problem
Post by: maru on 2017-03-03, 14:57:06
Fabio, did you send the scene using the uploader, or submitted a support ticket?
Title: Re: light problem
Post by: fabio81 on 2017-03-03, 15:13:55
yesterday by uploader, thanks
Title: Re: light problem
Post by: Ondra on 2017-03-04, 13:43:13
i forwarded the scene to Nik
Title: Re: light problem
Post by: burnin on 2017-03-04, 20:59:43
fabio81
you have an emitter a single quad?
Title: Re: light problem
Post by: fabio81 on 2017-03-04, 22:07:17
fabio81
you have an emitter a single quad?


I'm attaching the file, you'll notice that the problem is with the diffuse light.
Let me know thanks

https://drive.google.com/open?id=0B2rKEzkL1GAKWWZJU3c3cmZjMjA (https://drive.google.com/open?id=0B2rKEzkL1GAKWWZJU3c3cmZjMjA)
Title: Re: light problem
Post by: burnin on 2017-03-05, 15:24:38
yup, noticed it before
bad model - intersecting & single poly
make more detail, more geometry...

fix attached

(http://i.imgur.com/NPnUSl3.jpg)

Advice
learn what not to do & how to properly model for fast and bug free rendering

PS
tho some breakage in lighting can still be noticed ;)
i suspect something with the corona normal bug influencing the light emission... IDK for sure
for now subdivide emitters
Title: Re: light problem
Post by: fabio81 on 2017-03-05, 16:26:28
it is true in my light were missing subdivisions, but even now the result does not change, the problem is always there.
I saw that there is also in vray but the problem is solved by placing a light area.
In Corona however the problem remains even with light area
Title: Re: light problem
Post by: Cinemike on 2017-03-05, 22:07:04
This begs the question: Does Corona use their own, homemade arealight or does it use the one that is built in C4D?
The one that comes with C4D natively is composed of more or less single lights.
It might not be as obvious in Corona, because it has no fake highlights, but still be a problem.

Just thinking ;)
Title: Re: light problem
Post by: Nikola on 2017-03-06, 20:41:17
HI,

someone knows me explain why there are the spots on the wall?

Hi, to remove artefacts you can increase UHD cache precision by increasing precision or/and changing the preset in render settings, please see the attached image. But during testing of your problem we found that there is another bug, and we must investigate it more.
Title: Re: light problem
Post by: fabio81 on 2017-03-06, 21:49:26
HI,

someone knows me explain why there are the spots on the wall?

Hi, to remove artefacts you can increase UHD cache precision by increasing precision or/and changing the preset in render settings, please see the attached image. But during testing of your problem we found that there is another bug, and we must investigate it more.


yes Perfect!! thanks :D
Title: Re: light problem
Post by: Cinemike on 2017-03-08, 05:50:40
This begs the question: Does Corona use their own, homemade arealight or does it use the one that is built in C4D?
So I was on the wrong track? That's a relief!