Author Topic: Hard Caustics  (Read 2958 times)

2019-12-13, 17:40:10

aler

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At first liked the new caustic. But then decided to look at the interaction with water. And then notice that the result is too hard (pictures 1,2). Besides surprised that there are absolutely no caustic settings, only "Enable".
Tried "Caustics only in caustics pass" option, but this method can not achieve (in Photoshop) the desired result, it's limited.
Then looked, how caustics behaves not in shallow water, but at great depth (picture 3) and here clearly shows the same flaws - is too strong.
Therefore, there is a wish: add to global settings "Intensity from Distance" and "Blur from Distance" to allow more control.

2019-12-13, 17:55:56
Reply #1

Papuca3D

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Try making the scattering color in the water material lighter than black. If it's black, there will be no scattering and therefore no result. It's the scattering which lets you control the intensity of the caustics over distance. Just like in real life, really...
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2019-12-13, 23:11:36
Reply #2

aler

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Try making the scattering color in the water material lighter than black. If it's black, there will be no scattering and therefore no result. It's the scattering which lets you control the intensity of the caustics over distance. Just like in real life, really...
Scattering color... I know it. But his lightening strengthen opacity.
Generally opacity is regulated by 3 parameters: Absorption Color, Absorption Distance, Scattering Color. Between them need to reach a balance: correct color, degree of opacity, distance of opacity, luminosity of depth, luminosity at a surface... This hemorrhoids. This very BIG hemorrhoids :-(
What is the difference between Corona from VRay? Corona - it's easy settings, everything is done quickly, and then only need to press a button "Make beautiful" and all - will be beautiful :-) Well, VRay - need a whole day to adjust a lot of settings, to end up getting the same.
Therefore, in order not to become like the VRay, I suggested these 2 additional options: "Intensity from Distance" and "Blur from Distance" :-)

2019-12-15, 13:45:19
Reply #3

aler

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If my proposal, it is difficult, then could add at least 1 option - "Power of Caustics".

2019-12-16, 12:05:12
Reply #4

maru

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What you see is a realistic simulation of an effect that you see in real life (caustics).
There are no additional parameters like "caustics intensity", "intensity from distance", "blur from distance", etc, because such things do not exist in real life.
In reality, caustics are sharper or more blurry, more or less intensive, etc, depending on multiple factors such as:
- water brightness
- water clearness
- sun intensity
- environment lighting (e.g. whether clouds scatter sunlight)
You have those controls available in Corona and you can use them to adjust your caustics.


Therefore, in order not to become like the VRay, I suggested these 2 additional options: "Intensity from Distance" and "Blur from Distance" :-)
The effect would be exactly the opposite of what you are saying. Corona is not V-Ray, because it does not feature additional "fake" controls, even if they often mean more artistic freedom, it is more physically accurate, and makes it easier to get realistic-looking results out of the box.

If you really want to break realism to get some extra control over your caustics, you can use rayswitch material/map to use different material for water's direct visibility and water's caustics (GI component). You can for example create water with lower refraction glossiness, and use that to get more blurry caustics.


2019-12-16, 14:51:28
Reply #5

aler

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What you see is a realistic simulation of an effect that you see in real life (caustics).
There are no additional parameters like "caustics intensity", "intensity from distance", "blur from distance", etc, because such things do not exist in real life.
maru, thanks for the reply :-)
I understand that Corona - it's like in real life. It's like a camera - what he saw the same thing photographed. But sometimes it is necessary to weaker effect for artistic reasons.
Well. There's another variant - visualize twice (Caustic with and without) and then achieve the desired result in Photoshop ;-)
Ray Switcher I can't check - demo period v5 is over.

2019-12-16, 14:58:19
Reply #6

maru

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Yes, doing adjustments in post is another option, and that's why we have the option to render beauty and caustics separately.