PhotonGI cash problem

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PetrT
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Re: PhotonGI cash problem

Post by PetrT »

kintuX wrote: Sat Aug 28, 2021 7:24 pm Use of PhotonGI Cache makes results a bit darker.
Not sure, but I think it was already mentioned...
This topic about another problem.
Problem with shading solves when Environment Light Cache is turned off
kintuX
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Re: PhotonGI cash problem

Post by kintuX »

Righty then... not a problem really :D
PetrT
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Re: PhotonGI cash problem

Post by PetrT »

pic of test
Attachments
004.jpg
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Dade
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Re: PhotonGI cash problem

Post by Dade »

PetrT wrote: Sat Aug 28, 2021 7:24 am Test scene https://dropmefiles.com/lJ5Za
I'm looking into the problem.
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Dade
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Re: PhotonGI cash problem

Post by Dade »

It looks like the problem is related to the use of constant infinite light, if I replace the light source with an HDR infinite light source, it works fine:

hdr.jpg
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PetrT
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Re: PhotonGI cash problem

Post by PetrT »

thank you
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Dade
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Re: PhotonGI cash problem

Post by Dade »

Fu*k, this scene was driving me crazy, I was getting out all kind non sense results.

Your problem is just caused by an extremely low clamping value. If you disable variance clamping (or raise the value by a significative amount). The rendering will be fine.

You were "clamping" a tons of light, this is a rendering with your clamping value:

clamp.jpg

and this without clamping:

noclamp.jpg

You are clearing cutting half of the transported light (and causing artifacts in the process).
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Sharlybg
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Re: PhotonGI cash problem

Post by Sharlybg »

Fu*k, this scene was driving me crazy, I was getting out all kind non sense results.
As a reminder this should be put in the tooltips of clamping. ""Too low value can break lighting and create artifacts with GI cache """
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PetrT
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Re: PhotonGI cash problem

Post by PetrT »

Dade wrote: Mon Sep 06, 2021 12:50 pm this scene was driving me crazy, I was getting out all kind non sense results.
Sorry,It was not the aim of my post.
I guess just another interesting case
004.png
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Re: PhotonGI cash problem

Post by Dade »

PetrT wrote: Mon Sep 06, 2021 10:08 pm Sorry,It was not the aim of my post.
I guess just another interesting case
I'm not sure to understand the statement but I have the feeling you have to run the rendering without clamping to get a valid suggested value.
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