White noise in a shadow at 15,000 samples?

[Blendman96]

Hi,
I’m trying to render out this car wheel and tire I recently made and i keep getting this white noise in the shadowed areas. I’m even getting some on the black tire.

How do i resolve this?

Info on the material and scene:
The materials on every object closely follow blender guru’s new PBR tutorial. The scene is also lit by his Pro Lighting Skies demo, a nice HDR with brightness and rotation sliders. The screen shot above is using the preview render with a border set up so I could really crank up the samples on that area. The settings in the render panel are default for cycles. The rim is using a noise texture set way up to 10,000 to get that sparkling metallic paint effect, a spec map would probably be better but i would need basically a checker board on the pixel scale to get this effect.

I’m currently finished for the day so I’ll probably check this post tomorrow, roughly 18 hours, have to visit family tonight.

All suggestions and help is greatly appreciated.

Attachments

[rcpongo]

Those are often referred to as fireflies, and will take a ridiculous amount of samples to clean up. They are common on slightly glossy surfaces with an HDRI.

Fortunately, the solution can be easy. Change your “clamp indirect” value to a number like 1. It’s located in the render panel,… bottom left corner of your screenshot. That should mostly clean it up.

[theoldghost]

Not disagreeing with rcpongo who went from A to B in a straight line. Try clamping Indirect at six (6) say and then work down until they are mostly gone. Very easy to do since you are using Box Select. Clamping real low on my machine with some scenes effects the reflections.