Author Topic: Reflective dispersion issue  (Read 708 times)

2022-03-24, 15:21:21

Redesigned

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Hello! I have a problem like this, has anyone come across this, is there a solution?

2022-03-24, 15:39:12
Reply #1

Beanzvision

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Hi there, how many passes have elapsed for this image?
Bengamin Jerrems l chaos-corona.com
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2022-03-24, 16:42:47
Reply #2

Redesigned

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Hi there, how many passes have elapsed for this image?


This thing appears around 6-7 pass. And does not change throughout the render, up to 100-200 passes.

2022-03-24, 17:16:10
Reply #3

TomG

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Usually changed the Abbe number is what is required here, to "calm down" the intensity of the colors being created.
Tom Grimes | chaos-corona.com
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2022-03-24, 17:32:03
Reply #4

Beanzvision

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As Tom has suggested, please feel free to play around with a value that suits you. In my example, I increased it to 90.
Bengamin Jerrems l chaos-corona.com
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2022-03-24, 18:42:53
Reply #5

Redesigned

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Thank you for your answers, guys!
But I'm specifically trying to get a stained-glass effect. With a dispersion value close to "1". Something like that in the picture "ref".
But even with values ​​of 30-50, such artifacts appear in reflections. There is a feeling that the dispersion is multiplied. But only in some selective reflections.

Below is the variant "without" the problematic reflecting object. And one more option with a "minimum" dispersion parameter, and still there is a problem in reflection.

2022-03-24, 20:00:54
Reply #6

TomG

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I'd suggest lowering the Saturation in tone mapping (you can up the saturation in the volumetrics themselves to compensate if you wanted to preserve the strong green blue color in the glass), also enabling Sharpen and Blur and Denoising will help with the noisy look (not with the color intensities though :) ). I did end up messing around with the abbe number too just because I liked this look, but even with the original abbe it avoids the superbright colors in the rainbow area. Only ran it for 25 passes or so. I stripped the tone mapping stack down to just the minimum, LUTs and curves and Advanced Filmic could be used to further tweak.

Tom Grimes | chaos-corona.com
Product Marketing Manager | contact us

2022-03-24, 20:18:23
Reply #7

Redesigned

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I'd suggest lowering the Saturation in tone mapping (you can up the saturation in the volumetrics themselves to compensate if you wanted to preserve the strong green blue color in the glass), also enabling Sharpen and Blur and Denoising will help with the noisy look (not with the color intensities though :) ). I did end up messing around with the abbe number too just because I liked this look, but even with the original abbe it avoids the superbright colors in the rainbow area. Only ran it for 25 passes or so. I stripped the tone mapping stack down to just the minimum, LUTs and curves and Advanced Filmic could be used to further tweak.


Oh yes! I always forget about post-effects in my experiments. This might be a problem, thanks for your time!

2022-03-24, 20:22:41
Reply #8

TomG

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Most welcome, I hope it helps you find the look you are after! Dispersion for some reason can create these totally saturated colors, but they can be tamed with the tone mapping. Would be interested to see what you come up with :)
Tom Grimes | chaos-corona.com
Product Marketing Manager | contact us

2022-03-24, 20:35:36
Reply #9

maru

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Another idea would be trying the "photographic" LUTs that are included by default in Corona (VFB > Post > LUT > select one of the "photographic" LUTs). They often do wonders with colors that fall outside of the "usual" saturation. :)
Marcin Miodek | chaos-corona.com
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