OTOY Forums

Hi Paride,
Why is octane so bad with night scenes that have lights. No matter how long I render I still have noise and black pixels.

Can this be fixed?
I tried messing with sampling nothing works. Is octane just not good at lots of lights at night? Thanks
The image attached is after 50k samples

I wish devs remove sampling rate or make a new way for nights scenes with lots of lights. It's the biggest pain. What if you have 100s of lights and tweaking all these rates is a nightmare. (At least add a global parameter - reset all lightsampling rates to 1)

Also reflection of lights in specular textures especially with DOF is the worst. Pure noise. Honestly octane has the worst quality when it comes down to multiple lights at night or light reflection with DOF

What works for me, but I`m not doing night animations often:

- caustic blur - 1
- GI clamp to around 2000 or less (check to see the difference with say 100)
- Enabling AI light + denoiser
- Making sure adaptive sampling isn`t messing anything up (expected exposure should be correct)
- Never have 0 roughness or full white material
- Specular materials with 'fake shadows'.
- I always put sampling rate up to max

But most of the time the GI clamp does work wonders!

Greets

whersmy wrote:What works for me, but I`m not doing night animations often:

- caustic blur - 1
- GI clamp to around 2000 or less (check to see the difference with say 100)
- Enabling AI light + denoiser
- Making sure adaptive sampling isn`t messing anything up (expected exposure should be correct)
- Never have 0 roughness or full white material
- Specular materials with 'fake shadows'.
- I always put sampling rate up to max

But most of the time the GI clamp does work wonders!

Greets

Thank you! AI light did help. Unfortunately we use AO so no GI otherwise render times will be so much higher
Light and reflections for octane is still a tough problem to solve on a large scale

Cool!

I would say with scenes like this that 'Adaptive sampling' would help a lot also, is that enabled?

otoy, please add a button reset all light sampling values in lights and mesh lights to 1. have 100s of lights and light mesh textures is too much to go back and forth and set some lights back to 1 and some to another value

whersmy wrote:Cool!

I would say with scenes like this that 'Adaptive sampling' would help a lot also, is that enabled?

Yes. I think to get a clean image will have to render at 500k samples or more. For osme reason octane struggles with lots of lights and light reflections. We need at least a feature to give more samples to reflected lights

In dark environment, I found bepeg4d's comment in this post helps a lot:
viewtopic.php?f=9&t=60549&p=309888&hili ... 2A#p309888
not sure if your case related,just FYR.

Hi coilbook,
could you try to reduce specular, bump or normal map (road material)
Any emitters inside other objects?
viewtopic.php?f=27&t=60648&p=310376#p310376
Regards
Paride

paride4331 wrote:Hi coilbook,
could you try to reduce specular, bump or normal map (road material)
Any emitters inside other objects?
viewtopic.php?f=27&t=60648&p=310376#p310376
Regards
Paride

Hi Paride,
I tried it doesn't work much. Do you know by any chance why there are pure black pixels like in the iamge above or the one I attached? is it missing data? It was rendering for 50,000 samples

UPDATE:
I noticed it happens a lot when two or more lights shine at the same point (surface)

Thanks

What i dont get is how games use unbaked realtime RTX light (like this Cyberpunk game) noise free and we render for 2-3 min with tons of GPUs to get noisy light from frame to frame just because i have 20-30 lights in the scene .