Author Topic: refraction noise / optimization (?)  (Read 401 times)

2019-04-19, 12:49:26

vonlanthen

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hello world

im sure thousands of questions are asked about noise reduction. im rendering a scene with a gem stone (ruby). naturally cuastics and dispersion are on but when i do have them on, rendertimes are impossible for production. so i turned them off and managed without. but at UHD (2160x3840) the rendertimes are still a bit too high. now, maybe corona is like that and rendering refraction is in general a bitch or there is some optimization to make. i would hope that i can tweak something in the performance tab. unfortunately i cant share the scene file but i have 2 meshes in the scene. one is the ruby one is a frame that holds it. i used the sky object with a corona light material as a hdr to light the scene.
the render you see took about 1h 30-40min with 25-30 samples. i know that distance should dramatically influence the rendertime. i need it to be that close though. so rendetimes so far take around 2 hours.





« Last Edit: 2019-04-19, 12:53:56 by vonlanthen »

2019-04-23, 07:33:54
Reply #1

iacdxb

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Be the way which render preview you are using.... ?
Many icons and functions, Corona IR shows only passes status.

...
Mac OS X
Cinema 4D R20

2019-04-23, 08:44:14
Reply #2

vonlanthen

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Be the way which render preview you are using.... ?
Many icons and functions, Corona IR shows only passes status.

...

thats after effects. inside the square is a denoiser at work from AFX. but that should not be the isue. corona frame buffer or picture viewer in c4d, the quality is the same. the diamond is very very noisy. i tried it in vray the other day. after 20 min it was almost noise free. compared to corona after 2 hours thats really something :/
do you have any idea what settings i could tweak?

2019-04-23, 10:37:48
Reply #3

nkilar

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Don't want to discourage you but from my experience... I haven't found a way to cut render times when it comes to refractive stuff. GI / Lighting / DOF in general yeah but everything else not so much.

Since you are using caustics on (current implementation is tricky and slow) the render times are even higher. That is on the to do list as a Core thing for version 4 and afaik we haven't gotten a taste of it in the dailies yet. Haven't tested the 3ds Max version in a while so no idea what is up there.

V-Ray is faster but in my opinion it doesn't produce the best looking refractions out there. Might be just me though.

GPU renderers are usually incredibly fast with this stuff but I guess that doesn't help much at this point :)

2019-04-23, 13:18:55
Reply #4

vonlanthen

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thanks guys, really appreciate all the tips and experiences you have. yes at this point GPU is not an option since the project is now ongoing and in full swing.
yeah in the end refractions are just a bitch to render xD i hope they can do something about that in the next release. one of my main problems with corona compared to vray  is, that i dont know how to tackle noise properly. they tell us to leave the performance tab at default but when renders look like that, basically unusable you have to tweak something. and thats where my problems start. there is no in depth video explaining the ins and outs of what to do when X happens.