Lighting Noise using HDRI in Vray Dome?

[Streetwise]

I'm getting some nasty noise from a high res HDRI map in a dome light. I'm using IR/LC. The light is set to 128 subdivs. Also, I have an instance of the map in the environment slot. Anyhow, I'm looking at a 6hr. render and am wondering if upping the subdivs is the thing to try, or do I need to mess around with the dome light somehow?

[joconnell]

Hmm, from the looks of some of the panels in your objects have you got some double faces going on?

[Svetlozar Draganov]

Does the noise decreases if the HDRI map is removed?
Color Threshold value in the Image Sampler is way too high - may you revert it to its default value of 0.01 and run another test render.

[Streetwise]

There are no double faces that I can see. What I did discover is that a couple material subdivs were still on the default of 8. So bumping those up helped.

I set the Clr Threshold value down to .01 which certainly took care of the noise issue, but increased the render time 3-4x. I then took out the HDRI map and yes, that also helps with the noise issue.

In the end, I think I'm going back to the VRaySun / Skylight portal system until I can figure out how to best optimize using a single HRDR dome light.

[Art48]

I found an adaptive amount of 0.85 too low in most cases when going into high subdivs. I mostly have it at 0.95 to 0.98. It could lead to artifacts in low contrast or shadowy areas, but maybe try that since it casts fewer minimum samples into the scene. Its propably not the main source of your issues, but I guess it can help to some degree. Know what you are doing though. Read up on the adaptive amount if you're not sure what it does.