Strong noise in dark areas (vray 3.)

[crazy homeless guy]

Oy. Everyone has there own settings but those are extremely odd to me... though I will admit that I am old school in my choice of settings but they tend to work. It may be best just to upload part of the scene so people can look at it and offer you better advice.

[squintnic]

agree those look to be some very weird settings......
MSR 58?
0.0002?
2 / 98?
6.875 retrace

[Crayox13]

Those are from quick settings. I think it has a bug too...if you enter a number in it for AA and then use slider percentage goes crazy. I tried resetting it by typing 100 while slider was to the far right. Maybe it didn't work so it gave these numbers.

[stevesideas]

Is there a reason you have multiple lights on the outside instead of one large light to cater for all of them ?

[Crayox13]

Yes, I used to use SR so it set all my sampling to one value and if the light was bigger it produced more noise. So I kinda got used to that. Will change that to one light.

[crazy homeless guy]

I usually use multiple window lights and not one large light. Not sure if it still holds true but in the past using one large plane made the rendering much slower than several small planes. My guess it has something to do with samples needed to deal with the extremely large surface area of the Vray plane light.

[Crayox13]

Is there an actual vray reset button (so I unscrew all those settings )?
I guess changing renderer would reset it.

[Jiri.Matys]

Turn off probabilistic lights.
Change lots of lights on the sides to one big light. Dont make portals. If you use hdri and all vray lights are portals, dont use them at all.
Maybe there are more fix should be done, but without scene hard to tell.

Now I see some picture of your settings - its little bit odd. Use automatic subdivs or make brute force subdivs higher. Or use Irradiance map with some high settings.

[Svetlozar Draganov]

So in this scene I tried manual override of the light and put sampling of 100 and I still get this noise. Can I send it to someone so we get to the bottom of what is causing this and other noise areas in my scenes?
Thx

[ATTACH=CONFIG]34192[/ATTACH]

Yes, please send the scene to support@chaosgroup.com (request access to our FTP if needed), and don't forget to include a link to this thread in order to find easily where it came from.

[Zdravko.Keremidchiev]

There seems to be an issue with the Multiple Importance Sampling in this particular case. I've forward the scene to the developers for investigation.
For now you can either disable VRayDomeLight "Use MIS" option or you can revert to the old sampling method:

renderers.current.twoLevel_adaptiveMethod=0

[Crayox13]

Hm really! I was certain I screwed up some threshold with Solid Rocks or vray quick settings.
Thanks but what do you mean to use MIS and disable vraydomelight?

[Svetlozar Draganov]

There is a MIS option in the Light Options:

Disabling that option for the DomeLight in the scene will resolve the artifacts.

[Crayox13]

Hey guys,
has the
renderers.current.twoLevel_adaptiveMethod=0
changed with the new vray 3.50.04? Now I have s scene where this does not fix the weird noise. When I disable "use MIS" I get different noise.