Noise - Best Approach

[NorthVisualStudio]

Hi,

I'm rendering this scene and was hoping to get some advice on the best way to reduce the noise.
If you look at the video, the noise is obvious - regarding the Advanced Render settings and the Render Samples, what is the best way to optimise the noise in a scene like this?

Thanks, N

https://youtu.be/mkL7yoaodkY

Please view the youtube link - I can't get rid of the google drive link for some reason.

Mods, how can I delete the link below?

[npg]

Is this an offline render and which denoiser did you use? Could you screenshot your entire advanced render settings UI?

[NorthVisualStudio]

I'm using Live Link - the settings are below.
I've started increasing the settings to the following;
Noise Threshold to 0.002
Total Bounces to 30
Light Cache LC cell size to 0.020
LC Sample Limit to 1024
Enable Lights Tree to 2

After increasing the settings - it won't render!
Currently, I'm optimising the scene to reduce the overhead.

[npg]

After increasing the settings - it won't render!

What does this mean?

I'm still not sure if the recording was from offline ("high quality") rendering or a capture from the interactive viewport using DLSS. Which one is it? If it's offline did you use the Optix denoiser with "reduce flickering"?

If your scene has multiple lights, you could try the "Direct light reservoir resampling" option.

[NorthVisualStudio]

It was rendered High-quality with the Intel Open Image Denoiser.

When I changed the render settings to higher values as listed above and hit render - Vantage would not render, the Rendering HQ Sequence dialogue box would sit there and not render. When I change the output resolution from 4k to 2k, it works.

[npg]

the Rendering HQ Sequence dialogue box would sit there and not render

Strange, I don't think I've seen such behavior.

Anyway, the Intel denoiser should be the primary cause of this flickering - it does not support temporal stabilization yet (hopefully in some future version it will). Try using the Optix denoiser and enable "reduce flickering".

[NorthVisualStudio]

Thanks for that.

When reducing general noise and noise in glossy reflections, what is the best parameter(s) to reduce it?

[npg]

Probably just using more camera samples.

[NorthVisualStudio]

When I choose Nvidia Optix AI and tick "Reduce Flickering", I get lots of fireflies - attached.
When "Reduce Flickering" is unticked - the fireflies disappear.

[npg]

the temporal and nontemporal modes of the Optix denoiser use different neural nets, so they may have different issues like here. Try toggling the "Legacy mode" option in Edit->Preferences->Render. It will use yet another neural net. What driver version do you have?

[NorthVisualStudio]

I managed to figure it out.
The source of the noise was from the 81 lights illuminating the far side of the columns, this in turn was reflecting on the glass and creating the noise.
Anyway, I changed the Vantage settings to the attached - the main settings are Enable Lights Tree to 16 samples and turning on Enable Ray Termination.

One other thing I'd like to ask is how to reduce the amount of vram a scene needs to render, do you have any suggestions?

[npg]

Avoid displacement (or try lower tessellation level in Preferences);
Try to instance geometry when possible;
Use lower resolution textures when possible or try the new setting we added in 2.6.2 in the advanced settings under "dynamic textures" - change LOD bias to a positive value;
Avoid render elements in high resolution renders when possible;