Noise reducing Corona HQ vs NVidia AI vs Intel AI

[Kost4d]

Hello, colleagues!
Some time ago I did some testing of noise reducing algorithms in Corona Renderer, but did not notice huge improvement of speed using NVidia AI noise reducing. In the most cases I use Corona HG. On recent project I've got cool/fast results with Intel AI. But now... just in the middle of the exterior project I switched to NVidia AI and it rendered the 1280x720 @ 4 % of noise in 1 hour instead of 4 hours with Corona HQ.

Do I do something wrong usually and got this particular scene right this time? Or is this the kind of scene that runs fast with NVidia AI?

Does anyone have similar experience with NVidia AI? When should it be used mostly?

Thank you!

[TomG]

I am not entirely sure what you mean here - the choice of denoiser does not affect render times, only the time taken to run denoising on the final image. So unless denoising was taking 3 hours to complete (and just denoising, not rendering), then there is something else going on here. Also, if it WAS taking 3 hours to denoise, something is wrong there too :)

[Kost4d]

no, I mean somehow rendering goes faster and image looks clearer in less time then when using usual denoise method

[romullus]

When using Nvidia denoiser, the image always will look more clean, because said denoiser is running in real time and what you are seeing during rendering, IS denoised image. The other two denoisers starts only after rendering is finished. And that is main reason why i almost exclusively run Nvidia's denoiser, even if its quality isn't the best of the three.

[Kost4d]

When using Nvidia denoiser, the image always will look more clean, because said denoiser is running in real time and what you are seeing during rendering, IS denoised image. The other two denoisers starts only after rendering is finished. And that is main reason why i almost exclusively run Nvidia's denoiser, even if its quality isn't the best of the three.

Oh, yes! I did not think of it in this way... yes, what I see is already denoised!

[TomG]

But rendering speed isn't any faster (or slower) with any of the denoisers, just to re-iterate that point :) Target noise level or number of passes will still be reached in the same amount of time.

[Kost4d]

Thank you!

[maru]

But still, there shouldn't be any big difference in rendering time if you are rendering to specific noise limit (e.g. 4% here).
@Kost4d could you please send us your scene for further investigation? You can use this upload and then tell me what was the file name: https://corona-renderer.com/upload
If you cannot share your scene with us, maybe you can share a part of it?

[Kost4d]

I can not send current exterior scene, but I will prepare some personal "nature/dinosaur" scene which I believe tenders longer with NVidia AI