Noise in Glossy Shadows

[anthonygugliotta]

I've attached an image of the view in question along with snapshots of my "High-Quality" render settings.

 

 

I'm having difficulty reducing noise, particularly on dark objects with glossy reflections. As you can see the rest of the scene is quite clean thanks to the boost in Image Sampler Settings (Max Subdivs = 6) and a reduction in the Noise Threshold (0.005)

 

My problem is that the window frame (and even the side of the couch) is quite noisy. I've attempted lowering my noise threshold to 0.001, as well as increasing my image sampler subdivisions to 12 without noticeable improvement. The material settings for my window frame are:

 

(2,2,2) diffuse colour

(0.7) glossy reflections w/ 32 subdivisions

 

I also tried boosting the frame's material's subdivisions to 128, and the noise actually got worse; the contrast between the light and dark pixels increased! I did a test with the Global subdivs multiplier cranked to 4; the results were better but the rendering time was exponentially longer, and the frame was still noisy. I am using a Vray Dome to light my scene, and I've already cranked it's subdivisions to 32. This reduced the overall noise in the scene, but the frame remains a problem.

 

 

I'm not sure how to fix this?

Edit: I just realized the image uploader adds quite a bit of compression. The noise is much more noticeable on the original image.

Edited November 12, 2013 by anthonygugliotta

[anthonygugliotta]

Still having major problems with this. Any help is appreciated!

 

Edit: here are some low resolution render passes of my reflections and vray lighting. All the other passes are virtually noise-free.

Edited November 26, 2013 by anthonygugliotta

[anthonygugliotta]

Okay, I think I may have been able to figure something out.

 

I think this has to do with the relationship between material subdivisions and max subdivisions within the DMC sampler.

Before, I would increase the DMC max subdivisions and the quality went down which didn't make sense; however, If I understand correctly the relationship between min and max subdivisions is just a ration or fractional value of the subdivision value set within my material.

 

I found that if I keep my adaptive DMC at min 1 and max 4, and then boost my material's reflections subdivisions to 256 I get a near-flawless result. Still looking into this.

[dominikmateasik]

i think this article may help u http://www.interstation3d.com/tutorials/vray_dmc_sampler/demistyfing_dmc.html

[anthonygugliotta]

Yes, that's the one I read. Definitely makes it easier to understand DMC.