Denoising & Resume render

[Nejc Kilar]

Hello everyone,

I just have a quick question and I really appreciate the help already :)

I'm wondering what would be the correct way to stop a render with the intent of resuming it later. I'd still like to keep the option to denoise it later on when outputting the final image.

Right now I'd guess I can just Save the VFB (without stoping it which would cause the denoising calc) and resume it later. Would that be the thing to do?

Thanks!

[James Vella]

Save VFB option in the Save/Resume rendering section

You can also set it to auto this .exr out in the System > Output autosave section in case it crashes or doesnt save out the RGB

[Nejc Kilar]

Thanks for that! I knew about Save / Resume rendering though but I am unsure if it works properly with the denoising feature.

For example, stopping the render now, saving the VFB (Save / Resume rendering) would mean that denoising gets calculated and then when I resume I guess the resume will introduce more noise that might not work well with the next denoise pass.

[sevecek]

For example, stopping the render now, saving the VFB (Save / Resume rendering) would mean that denoising gets calculated and then when I resume I guess the resume will introduce more noise that might not work well with the next denoise pass.

Denoising should work properly even if you stop the render and then use "Resume last render". It doesn't matter that the denoising has been calculated, it will be calculated again.

[Nejc Kilar]

@sevecek, thank you. I guess that pretty much clears any confusion I had on how to use the thing... Awesome, Sir!

[James Vella]

interesting point you raise, i remember reading somewhere that the denoiser was meant as a post effect. But Im not getting the results I expected...

10 minutes with denoise set to 0.4



I then went to Render Dialogue > Scene > Save/Resume rendering > Save VFB... to exr file. I then cleared the VFB, loaded it back in, denoise didnt work. So I set it to resume for 1 minute and apply the denoise



Much more noisey, which makes sense if its only calculating this data from the second render... not accumulating it from the saved exr. Is there some documentation as to how this data is computed or stored?

[maru]

I would say it looks like there is no denoising at all. Are you sure you set the denoising amount in vfb to more than 0?

[James Vella]

Yes its on. I chose 0.4 so you could see a visible difference. For the test.

Edit: i was hoping i could resume a render later and it stores the denoiser data with it. I dont understand how the denoiser can be totally utilised if i do a 6hour render and it crashes. Probably dont need denoise after that long but im curious as to how it works or if i can reuse the data for a re render  per se with minor changes like color or something.

[Cheesemsmsm]

It works fine for me.

Please make sure if your EXR file has these layers.
After resuming, make sure you're on rendering stage, not scene parsing / gi precomp. then click on STOP button, not cancel or press ESC.

cheers