Denoiser is creating odd sparkles in the image

[rcollett]

We have been using the new Denoiser for a few weeks now and I've come across some odd splotches or speckles of light that the denoiser makes in some select places and circumstances. In one scene we did, there was a small object on the ceiling with the Ward BRDF type that was causing these speckles. Switching the BRDF to Microfacet got rid of the speckles. I've now got a scene with a swimming pool that is creating a massive number of artifacts along the edge of the pool. I've been able to trim the scene down to a minimum number of objects to share here.

Here is the RGB channel:


And the Denoiser (Default preset):



I've posted the scene file here:
https://drive.google.com/open?id=0B2...DlRYjB4MzJRR0U

I'd like to figure out what is causing this.

Ray

Forgot to mention some stats:
Max 2015 17.0 SP4
VRay Adv 3.50.04
Intel i7, Nvidia 1080 GTX

[tashko.zashev]

Hi,

I see lot of white specs on side walls which actually are reflective GI caustics. Perhaps the denoising operation is not able to interpolate between such huge difference between the pixel values and transforms them into bright splotches.
I would advise you to turn Max Ray intensity on for this setup and this way the Beauty pass will be much smoother in those areas. Another option is to untick Reflective GI caustics from the GI section if you don't need them.
Hope this helps you.