Emission Fall Off And Noise

[RJMEngineering]

Hi All, having a couple of problems still when trying to render emission materials in dark environments, getting a LOT of noise! Have used Gaussian spectrum which has improved things greatly, but still getting a lot of issues. Any help?

Below is the render

Below shows the settings I am using, but another thing I cant figure out is how to invert the falloff map so its light in the middle and dark at the edges!

All help is appreciated

Ritchie

Dark Emission Test.zip

(730.87 KiB) Downloaded 117 times

[bepeg4d]

Hi Ritchie,
since you are spreading up to 1500 light source in the scene, my suggestion is to untick the Cast illumination option in all the emission node, and mimic the light effect with an invisible light source of the same color.
ciao beppe

[RJMEngineering]

Thanks Beppe, I just don't know if that would work as it is meant to be part of an animation. I am always struggling with noise where there is no sun or HDRI, any thoughts??

Ritchie

[atome451]

Hi Ritchie,

This is a nice challenge.

Width is very short in your GaussianSpectrum nodes. As there is only this kind of colored lights in your scene, i've given a try to another solution: a higher width in GaussianSpectrum but a strong saturation to restore the color. The problem is, when the width is very short, the noise start to be similar to a RGBSpectrum. I'm not sure but i think this kind of effect in real photography would be managed in the same way: more saturation in Photoshop...

I've touched to almost everything. Here a sample file. Not perfect but with some more samples, it should be good for an animation. I've tried to stay near to your render time. It's just a test for the fun, i'm not sure my values are better in any cases.

Dark Emission Test atome451.zip

(732.58 KiB) Downloaded 148 times

[RJMEngineering]

Thank you for the reply and the effort, it's really appreciated. I will have a look when I get back to my comp, but to be honest anything is going to be a bonus. Just not sure how you guys generally deal with dark scenes with only a few lights and keep the noise as acceptable

Ritchie

[atome451]

Ah yes. For the Fallof, you may invert min and max value to invert the effect. Or you may add an Invert node after the Fallof.