V-Ray GPU Denoiser Not Updating Progressively During Production Render

V-Ray V-Ray GPU V-Ray GPU :: Issues
1

I’m experiencing an issue with the V-Ray Denoiser when using V-Ray GPU in Production Rendering mode.

During rendering, the denoiser updates correctly while the Light Cache phase is running, but once the actual render starts, the denoised image no longer auto-updates progressively. The denoised result only refreshes at the very end of the render.

On previous V-Ray versions, and also when rendering with V-Ray CPU, the denoiser was updating progressively during the render as expected.

Is this a known limitation/bug with the current V-Ray GPU version, or is there a setting that could affect this behavior?

Thanks.

2

This was already discussed in this thread.

3

The devs just told me this was fixed in the latest hotfix (7.30.04). Mind if you try it out?

4

Thanks, I just tried it. It’s nearly there.

Now, in GPU production rendering, the denoiser shows up for the Light Cache pass, but during the actual render the denoiser layer turns itself off. To visualize it while rendering, I have to manually click the layer to enable it again, then press the Update button every time I want to check the result.

On CPU, the denoiser stays active and updates automatically.

I’m not sure if this is the intended behavior for GPU rendering, or if I’m misunderstanding something. Personally, I think it would be better to have an option allowing the user to choose whether the denoiser auto-updates or not. I’d be fine sacrificing a bit of GPU performance if I explicitly choose to keep it updating live.

5

That’s by design to avoid performance loss. There’s a note about it here:

When using production rendering with Progressive sampler the Post-effects update rate option is disabled to avoid any performance loss. To update the denoiser, select the denoiser layer in the VFB and click on Calculate.

It’s automatic for IPR only.

Otherwise, this being optional is a valid idea. @Muhammed_Hamed should consider it.

6

Thanks for the fast reply.

Having this option in the future would be very nice. I have to say that for a long time I thought this behavior (the denoiser not auto-updating during GPU production rendering) was actually a bug.

It’s a bit annoying in daily use, but I’m glad to hear it’s possibly being discussed internally. Let’s see how it goes.

7

Hey @gaara_the_nightmare

This is the intended temporary behavior for now.

The denoiser currently has a significant performance impact during rendering, so we decided to disable it for production rendering for the time being.

We have an update coming soon where denoising and lens effects processing have been improved to the point where they no longer interrupt the rendering process. With that update, we plan to revert this behavior.

Let me know if you would like access to test this improvement.

Best,
Muhammed

8

Hi @Muhammed_Hamed ,
Thanks for your reply. Yes, I’m always interested in testing new things. Let me know when you have a version available for testing.

Best,
Vincent