Grainy renders with glass like materials

[t@podlovics.hu]

I was wondering if anyone can help me with this issue. When I have glass surfaces in my scene the renders become very grainy/noisy.
I have experimented with turning Reflective/Refractive caustics off, increasing Progressive sampler subdivision, but nothing worked, except lowering the Noise threshold to extreme low value (0.005), but that means a lot longer render time
I am using GPU rendering with GeForce RTX 2070 super card
Anyone with a healthy solution?

[RwVision]

Hi

You just discovered the most annoying Vray5 noise problem Seems like reflections don't want to be noise free (visible also on the piano sitting). Raising min aa or anything does not work, only some ridiculously low threshold helps, but generates long render times. It's mostly due to awful Brute force GI, which generates uneven noises like this. Also feels like the aa settings just don't work.

Can't be much of a help - I've started some topics on this too. Unless you want to play with the stage lighting or unusable Vray5 denoiser...

[t@podlovics.hu]

Thanks for the reply. I really enjoy vray5 and Gpu rendering, but this noise is a quite annoying problem. Anyone from Chaos cares to comment?

[YunalZobu]

I tried to quickly recreate a similar setup to yours with some in camera dof and frosty glass look. Rendered it out with the rtx defaults.
I could take a closer look if you could share a simplified version of your scene

[aleksandar.kasabov]

Hello,

As Yunal said, taking a look at a simplified version of your scene could help us give you directions on how to improve your renders. You can also check this article to find the best settings for your project.

[t@podlovics.hu]

I tried to quickly recreate a similar setup to yours with some in camera dof and frosty glass look. Rendered it out with the rtx defaults.
I could take a closer look if you could share a simplified version of your scene

I will upload a simplified scene next week, as I am on a holiday now. However, just to emphasize: there is NO frosted glass in the scene, just regular transparent glass. And the noise appears behind the glass and also on glossy surfaces. No DOF either

[t@podlovics.hu]

OK, here is a very simple sample scene, like a room interior with a glass cubucle in the corner, like a shower. It is grainy as is with the default vray values. Please someone make the circled areas grain-less, without going to 0.005 valuse of noise threshold

[aleksandar.kasabov]

Hello t@podlovics.hu,

Upon checking your scene I can see that you have even noise distribution across the scene. If you wish to reduce this noise you will also need to lower the noise threshold. You can also try the new Intel Open Image denoiser which produces a noise-free image without lowering the noise threshold.

Also, please check the following article which gives tips on how to improve your render quality and render times.