Author Topic: GI irritations?  (Read 3897 times)

2015-03-26, 09:34:54

shen.de

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hi guys ...

stumpled on a problem in my latest little project. I marked the suspiscious area and the lighting in the second attached pic.

it's just lit by two areas and the corona sun object.  the object araound this area are white glossy materials (200/200/200), whtie diffuse (195/195/195) and some chrome with different roughness on the pots and pans ...

any idea? I checked it twice but cant get rid of it ... I dont want to put another lightsource there because I dont want it to look extracte from the rest.

any hints or ideas?

thanks in andvance

2015-03-26, 09:40:23
Reply #1

romullus

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There's no need in those area lights at all. That approach is wrong and gives bad results in Corona. Remove area lights and let enviroment map (HDRI or CoronaSky) do the job.

https://coronarenderer.freshdesk.com/support/solutions/articles/5000501978-how-to-set-up-hdri-environment-

Also you can help renderer a bit by placing portals into windows openings.

https://coronarenderer.freshdesk.com/support/solutions/articles/5000501660-how-to-use-light-portals-in-corona-
« Last Edit: 2015-03-26, 09:43:47 by romullus »
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2015-03-26, 10:19:52
Reply #2

maru

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And if you want to add background behind windows, take a look at this article:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000515605
Marcin Miodek | chaos-corona.com
3D Support Team Lead - Corona | contact us

2015-03-26, 10:37:48
Reply #3

shen.de

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thanks for.  I'll check the links ... 

I had the same issue with corona sun and sky.

I changed to areas to achieve the look I wanted shadow strength wise. the area technique worked well in another project so I thought I give it a try. maybe try hdri ... but I don't really like the handling of it at this point.

I'm on the latest corona for cinema version. there's no portals atm, right? at least haven't found them.

2015-03-26, 10:39:51
Reply #4

maru

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I'm on the latest corona for cinema version. there's no portals atm, right? at least haven't found them.
Oh, this is Cinema version? I was about to ask which version this is. :) I guess these errors might be because C4D version is still in early stages of development.
Marcin Miodek | chaos-corona.com
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2015-03-26, 10:47:09
Reply #5

shen.de

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I'm on the latest corona for cinema version. there's no portals atm, right? at least haven't found them.
Oh, this is Cinema version? I was about to ask which version this is. :) I guess these errors might be because C4D version is still in early stages of development.

I guess so ... I came across this problem 2 or 3 times in other projects and it was always when there are chrome or metal materials around it. that's why I sad "irritation" in the first place ^^


P.S. I'm aware of the backgroudn placing ;) this is just a placeholder in der psd file ... I did the backplate with emission in my london apartment project in wip section...

2015-03-26, 11:37:23
Reply #6

Ondra

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can you try switching GI to PT+PT? The render will take longer, but we will see if the problem is caused by Corona, or if the light pattern should really be there
Rendering is magic.How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2015-03-27, 09:16:26
Reply #7

shen.de

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can you try switching GI to PT+PT? The render will take longer, but we will see if the problem is caused by Corona, or if the light pattern should really be there

good morning...

just to let you know ... PT+PT had the same problem.

I had to render with sun+sky+area in windows ... than the shadow ist still there because of the geometry but it's not that unnaturally accentuated and looks right after all.

thanks for the help ...

2015-03-27, 10:31:26
Reply #8

Ondra

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ok, if it happens with PT+PT, then it is supposed to be there ;)
Rendering is magic.How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2015-03-27, 10:48:37
Reply #9

maru

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I now realized that there is a gap between the shelf and wall. Human brain is a tricky bastard. :D
Marcin Miodek | chaos-corona.com
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2015-03-27, 11:54:47
Reply #10

romullus

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Did you try to render without area lights, with contrast in VFB set to 1.0?
I'm not Corona Team member. Everything i say, is my personal opinion only.
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2015-03-27, 16:06:02
Reply #11

shen.de

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Did you try to render without area lights, with contrast in VFB set to 1.0?

yes. thats what I did in the first place ... after realising a light greyish strangly looking shadow on the wall I changed to area's for testing purpose because it worked well in another project.

in corona years I'm just a week old ^^ ... i'll figure it out as I go. and thats the fun part of learning and mastering something new.

thanks for the quick help and responses!