Author Topic: Mie & Rayleigh atmospheric scattering  (Read 3720 times)

2019-01-18, 18:58:39
Reply #15

dvdufo

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Here is the link to "HOW TO CREATE PLANETARY ATMOSPHERE WITH CORONA C4D" by Shawn Astrom.
https://lesterbanks.com/2018/11/planetary-atmosphere-corona-c4d/

I tried to go step by step by his guides, not in C4D but inside 3DS Max and corona.
I noticed that max version of corona, lacks the "Mix Mode" option for texture in Corona Volume Material in Absorption & Scattering section.
He uses Fresnel map in both Absorption & Scattering texture with Mix Mode set to Multiply to fade edges of atmosphere.
Anyone know how to do same or something similar to reach that fade effect on edges of Atmosphere?
I tried to reach that with Corona Distance & Fall off map but with no success.
Here's my render
https://imgur.com/a/eCMwN0w


2019-01-18, 22:22:43
Reply #16

juancarlosgzrz

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Do not use fallof, use a gradient map to drive density.


2019-02-09, 15:15:18
Reply #18

dvdufo

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Thanks juancarlosgzrz for your reply but actually I couldn't reach to my wanted result.
I used radial_gradient.osl too but I may missing something, and I can't get them to work as realistic fade on edge of atmosphere.
Actually I can reach my wanted effects in simple Corona MTL like assigning a FallOff map or GradientRamp to Opacity slot and making edges go fade but when using CoronaVolumeMaterial, it behaves as sharp edge shrink instead of fade.
I uploaded 3DsMax scene file with materials I used on slate material editor. I hope someone can help me.
Thanks.
« Last Edit: 2019-02-09, 15:52:40 by dvdufo »

2019-02-09, 18:53:45
Reply #19

sprayer

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this effect you want?

I used falloff map because for gradient ramp you need uvw map, you rotate camera so it won't properly placed, but it's possible if you make camera angle perpendicular to plane uvw

2019-05-11, 23:56:33
Reply #20

dvdufo

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Thank you Sprayer. Yes, this is what I want on atmosphere edge. But there's a problem.
On zoomed renders your falloff method works great, I copied your falloff map to mine, both looks well in zoomed but both looks fake on zoomed out renders, specially mine :)
in fact adding falloff affects atmosphere's realistic look.

2019-05-12, 09:46:32
Reply #21

sprayer

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Not sure how you  want it to look on zoom out view, if you want it to increase the size you may adjust radius of atmosphere sphere object and adjust curve in falloff map with distance in coronaVolume shader