Octane Noise Issues

[3dgeeks]

Octane does beautiful rendering for daytime and small studio scenes however, I think the devs really need to address some major problems with noise and sampling. As a studio doing 100% Octane we are constantly running into noise problems primarily in animation. The noise problems make Octane almost unusable for a lot of scenes. In particular :

1. Noise generated from network rendering to different computers. ie Octane produces different amounts of noise on different hardware. This produces noise jitter when rendering across multiple computers. I would have thought that asking Octane for a constant set of samples would produce the same noise.
Heres an example piece of test footage :https://www.dropbox.com/s/kiqt1pllvthdhq4/Octane%20Noise%20Munt.mp4?dl=0

2. Noise when looking though glass to a scene lit by artificial light. This may work using very high sampling but is really nasty when using for animation. Perhaps an architectural glass shader would fix this where Octane assumes zero thickness and an undistorted refraction (maybe with a slight offset).
3. Any scene using small lights or emissive materials. Im not sure how this could be fixed, I suppose it would require some sort of sample biasing?

So Im planning on putting together some simplified scene that highlight Octane Achilles heel, that Jimstar and the team can hopefully look at, and make Octane as awesome as it should be. ok it is awesome........ but seriously .

[3dgeeks]

Heres is my test scene that highlights a few of the problems that Im referring too. Now remember that this is a very basic scene, the problem only gets worse when more detail gets added such as plants, grass.

Test octane Noise perfect storm.zip

(119.69 KiB) Downloaded 284 times

This is at 2000 samples, which hopefully should be enough for a simple scene.

[3dgeeks]

So we ran some tests for case 1. Different noise from different computers.

We found that on a 2 card rig that the noise was rougher for the same no of samples when we disabled one card. So it seems that maybe Octane interpolates the noise between cards which is great for a still image, but bad for rendering animation to multiple computer renderfarm.

[gabrielefx]

don't use ies light and you'll be ok

I remember that 1.18 Octane release generated less noise, I don't know why every new release generates slight more noise...
In the past Octane render worked differently, now it works through several layers, the final images have several channels.
I remember that I needed just one 4xgpus workstation to complete a 1920x1080 frame, now I need 8 gpus in distributed render mode for the same scene rendered with pmc.
Octane render is great but slow, produces the best photorealistic images but generates a lot of noise.
There are many tricks to avoid the noise, sometime is impossible to apply them.

regards

[suvakas]

Could you export the scene to Octane format?

Suv

[3dgeeks]

don't use ies light and you'll be ok

The current render is without IES. Any small light source tends to be very noisy, even if its a mesh light and illumination is turned off.

Could you export the scene to Octane format?

Uploaded here is orbx, i have modified it to also have IES lights at the right.

Test octane Noise perfect storm.orbx

(826.77 KiB) Downloaded 260 times