Chaos Corona Forum
Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: grebano on 2014-09-08, 22:41:20
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Hi all
I have this scene lit by 3 chandeliers which is giving me noisy white spots in corners.
The chandeliers are quite complex: i have 6 lights inside each one and light passes through a cascade of slightly white glass spheres.
I've tried PT+PT and PT+HDC, i've also tried to double the AA resolution but i can't get the white spots to disappear.
I've also gone up to more than 550 passes and got the same result.
Since the chandeliers are lit quite uniformely i assume it's not due to their reflections.
Can someone shad light on this issue?
thx a lot
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Are you using "round corners" feature on those materials that are catching bright spots?
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Yes, the glossy wood has rounded corner at 0,2cm with 10 samples, while chrome material has 0,1cm
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Materials with high specular reflection and round corners enabled, becomes quite picky when there's strong small light sources in scene. You can try to increase round corners samples, but IDK if it'll helps.
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RULE NUMBER ONE NEVER USE EXTREME VALUES LIKE 0 or 255 in you r color picker
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RULE NUMBER ONE NEVER USE EXTREME VALUES LIKE 0 or 255 in you r color picker
Actually, that is rule number two. Rule number one is "Never ever write your posts in capital letters"
As for the problem. I would try following:
1, Increase rounded corners samples. Try to double them. Let's say 20.
2, Decrease GI/AA balance to something like 4-8, to focus more samples in Antialiasing.
3, Your chandelier is very fine, made of very tiny superbright spots, and your edges very tight and reflective. Especially if you have also very reflective materials, it could easily create this random spots effect. But that means it would also look that way in real world. The reason why it looks so weird on the rendering is because there are no secondary optical flares. In real world, or when you take a picture with camera, you always see some glares and flares on the small bright spots. If you took a photo somehow without these effect, all those highlight would look like fireflies.
So you can try to make selection by brightness in photoshop, and apply very small tight glares on all those bright spots to make it look natural and realistic.
Here's an example:
(http://img.auto.cz/news/img/art/2013-11/620_513ee36de1da3.jpg)
You can see this car has a lot small bright spots reflecting on it, but they all have little glow outline around them. If those blurry outlines weren't there, then it would look wrong to your eye. It would look like fireflies ;)
4, As a last resort, you can try disabling chandelier lights/components visibility for reflection, and then create some simpler object resembling chandelier, maybe just textured cylinder, and make it invisible to everything except reflections ;)
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Thank you very much guys.
Turning off the rounded corners option solved the problem.
I've quad chamfered every corner and replaced the roundness with geometry.
However the noise pattern looked so random that i don't know if it actually resembled to a "real life" reflections of the chandeliers.
On glossy materials without RC activated they reflected just fine.
I haven't tried increasing the rounded corners subdivision because i'm on a tight deadline but i'll give it a try later.
Regarding rule n.1 (or 2 if you wish), there are no extreme values in this scene :)
Thanks again
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3, Your chandelier is very fine, made of very tiny superbright spots, and your edges very tight and reflective. Especially if you have also very reflective materials, it could easily create this random spots effect. But that means it would also look that way in real world. The reason why it looks so weird on the rendering is because there are no secondary optical flares. In real world, or when you take a picture with camera, you always see some glares and flares on the small bright spots. If you took a photo somehow without these effect, all those highlight would look like fireflies.
So you can try to make selection by brightness in photoshop, and apply very small tight glares on all those bright spots to make it look natural and realistic.
Here's an example:
You can see this car has a lot small bright spots reflecting on it, but they all have little glow outline around them. If those blurry outlines weren't there, then it would look wrong to your eye. It would look like fireflies ;)
I wish Corona someday could render glare effect, even if post processing one.
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I wish Corona someday could render glare effect, even if post processing one.
That's actually planned. It should have been implemented already when internal res default was changed to 1 :)
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I wish Corona someday could render glare effect, even if post processing one.
That's actually planned. It should have been implemented already when internal res default was changed to 1 :)
I'm eagerly awaiting this! The car photo shows just how critical this feature is (yes it can be done in post, but getting physically correct glare / bloom would be a godsend!)
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Very glad to hear it. I hope, we can kiss goodbye those nasty aliasing problems with very bright light sources, once glare will hit the build!
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Will corona 1.0 gonna fix this "rounded corners" issue? Or should I keep using quad chamfer?