Sparkle Render Issue

[logan_mcnay]

Hey all,

When using Vray GPU, I can't resolve these sparkles in my render. Does anyone have any advice?

I tried a few methods:
Up the Samples limit a lot, lower the noise limit a lot - all the way up to 10,000 Samples limit, .001 noise
In Light Cache, switch from still, to Animation - Default animation numbers

Still these techniques don't change that I continue to get sparkles, the sparkles get lessoned at times, but they don't go away. Adding Vray denoiser actually makes it worse
No denoiser:

With Denoiser, the denoiser turns the sparkles into bigger blocky sparkles.


Computer specs:
AMD Ryzen threadripper pro 5975WX 32 core
256GB RAM
SSDs
2x Nvidia 4090 Geforce RTX cards

[hermit.crab]

Try the suggestions from here.

[trainofthought]

This, I believe, is not a general fireflies / noise issue, but actually a fundamental problem with Vray GPU RTX and motion blur. I get this same noise over everything on occasional frames, but not others - The only way I found I could resolve it was disabling motion blur or switching to CUDA which renders out the same frame fine (but obviously slower) Could we please report this as a bug on RTX? I'm also using the approved nvidia driver version on the latest version of Vray 6 for maya. Same issue happens when rendering on either of my GPUs or both of them (RTX A4000 and 3080Ti)

[logan_mcnay]

Thanks I totally agree, I think it's a bug. It's for this reason I've started going all CPU renders now because GPU rendering feels very inconsistent whether I get bugs like this or not which is a bit of a bummer. If there's a place to go to to report this I will

[trainofthought]

It is indeed a bummer that GPU still isn't quite ready for primetime, though it's a lot better than it used to be... I cry for your 2 x 4090s!

[Muhammed_Hamed]

Hey guys,

There is a fix in nightly builds this should be better now, the fix will be included in the next release.
In the meantime, please send me a scene so that I verify it is working fine now. This will be very helpful, thanks!
muhammed.hamed@chaos.com

On another note, rendering with CUDA over RTX is fine. CUDA mode has been improved a lot recently and will be mostly as fast as RTX in production

best,
Muhammed