Author Topic: Caustics for Fun  (Read 432 times)

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Offline DMerz III

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Caustics for Fun
« on: April 17, 2019, 09:29:37 am »
 :) I just love caustics.

Had a bit of a fun competitive challenge at work, whipped this up rather quickly with a bottle I modeled while back, and played with the new spotlight in KS8.
Used interior mode; 24 RB, 10GI, 5 shadow quality. Only 50 samples in this image (1200px by 1200px), super quick and cleaned up much faster than I thought.

Photographic mode with contrast at .15 - bloom is set and utilizing the bloom threshold.

Zero photoshop (other than assigning a color profile).



Offline Magnus Skogsfjord

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Re: Caustics for Fun
« Reply #1 on: April 18, 2019, 05:02:06 am »
That's pretty incredible that it's only 50 samples in this image. I usually struggle a bit with splotches when doing caustics, so it usually takes some time before it cleans up. Proves that a well adjusted foundation may do the difference. Very well done man!

Offline Esben Oxholm

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Re: Caustics for Fun
« Reply #2 on: April 19, 2019, 03:39:47 am »
Cool! The crop feels a bit tight on the bottle, but looks nice nonetheless.
In my experience the caustics cleans up quite fast as well when using the spotlight compared to a regular HDRI.

Quote
I usually struggle a bit with splotches when doing caustics, so it usually takes some time before it cleans up.
It also depends on the rest of the scene. Large surfaces with just some reflectivity will often cause splotches all over. I suspect Davids ground to have a basic diffuse material applied? Is that correct?
There are a couple of workarounds you can do to fix this without an unreasonable rendering time and I think you'll like my next tutorial. Coming up next week. Will post it here once it is up.


Offline DMerz III

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Re: Caustics for Fun
« Reply #3 on: April 22, 2019, 12:20:05 pm »
Cool! The crop feels a bit tight on the bottle, but looks nice nonetheless.
In my experience the caustics cleans up quite fast as well when using the spotlight compared to a regular HDRI.

Quote
I usually struggle a bit with splotches when doing caustics, so it usually takes some time before it cleans up.
It also depends on the rest of the scene. Large surfaces with just some reflectivity will often cause splotches all over. I suspect Davids ground to have a basic diffuse material applied? Is that correct?
There are a couple of workarounds you can do to fix this without an unreasonable rendering time and I think you'll like my next tutorial. Coming up next week. Will post it here once it is up.


Yes, the spotlight vs bright HDRI made a big difference here with the cleanup. Also, my settings are quite high for Indirect/Shadow quality etc. So while it is only 50 samples, they are 50 expensive samples (regardless, it did render fairly quick).

My cropping is tight for sure Esben, this was originally just a quick test, which turned out better than expected, so I kept it and thought I would share. The camera was setup for my standard bottle shot (client wants little to no space on the edges, these are typically on a transparent BG). The BG is a simple diffuse, so you're correct about the reflectance not being an additional issue for calculations.

 :)