Volumetric caustics in the wild

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aidalgol
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Volumetric caustics in the wild

Post by aidalgol »

I've been playing around with volumetric caustics in Blender with LuxCore, and while the renders take forever, the results are stunning. I can see why it's almost never used in animation, but I have seen scenes in CG movies with light shafts with visible dust floating in the air, and I was hoping someone here could tell me how that effect is faked without using real volumetric caustics.
CodeHD
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Re: Volumetric caustics in the wild

Post by CodeHD »

I guess for the most part it isn't even faked, they just use massive render farms ;)
This seems to be a recent blog post on the subject, featuring some extreme numbers:

https://www.awsthinkbox.com/blogs/the-e ... -rendering

e.g. about Lord of the Rings it says:
However, that's nothing compared to the character Treebeard, who had so much epic detail that it took up to 48 hours per frame to render the character.
If you are interested about a specific movie, you should name it, maybe someone does know details :D
epilectrolytics
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Re: Volumetric caustics in the wild

Post by epilectrolytics »

LuxCore is not really meant for faking ;)

I made volumetric caustic animations some time ago with BiDir, see here or here.
It would render even faster now with light tracing and OIDN but on my system the brightness is not consistent from frame to frame.
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aidalgol
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Re: Volumetric caustics in the wild

Post by aidalgol »

CodeHD wrote: Sun Dec 22, 2019 1:45 pm If you are interested about a specific movie, you should name it, maybe someone does know details :D
If I recall correctly, all the scenes I had in mind are from Pixar movies, so they probably are just rendering insane lighting effects, and not faking anything.
epilectrolytics wrote: Sun Dec 22, 2019 2:27 pm I made volumetric caustic animations some time ago with BiDir, see here or here.
It would render even faster now with light tracing and OIDN but on my system the brightness is not consistent from frame to frame.
Those are really cool! But yeah, three days for four seconds sounds about right. :P
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Dade
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Re: Volumetric caustics in the wild

Post by Dade »

aidalgol wrote: Thu Jan 02, 2020 10:51 am
CodeHD wrote: Sun Dec 22, 2019 1:45 pm If you are interested about a specific movie, you should name it, maybe someone does know details :D
If I recall correctly, all the scenes I had in mind are from Pixar movies, so they probably are just rendering insane lighting effects, and not faking anything.
Keep in mind than some of the latest Pixar movie required more than 2 days on an high-end CPU for rendering each frame: their software is good but they have a lot of brute force too.
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