pure chrome reflections produce noise

[braveRabbit]

Hi, I am currently working on a render and appear to have some issues with clear chrome like reflections. The model features some chrome strips and that have a VRay mtl applied with reflections set to almost 1 and glossyness also at 1. As a renderer I use the DMC sampler and the threshold is already at 0.004 - but still the chrome line shows some fine pixel noise that I can't seem to get rid of.
Any suggestions what can be done here? I colored the piece in question red because otherwise it might be hard to differentiate from the other pieces.

Thanks in advance, Ingo

[joconnell]

Use lower aa and higher the material subdivisions a lot!

[braveRabbit]

I am using fully adaptive control. I think adjusting the material subdivisions don't work then. Of course I can still lower my AA threshold but I am already getting pretty long rendertimes

[mr furious]

Turn off texture filtering in mayas file reads. Good place to start. It could reduce a lot of filtering issues as Vray does it's own filtering.

A

[braveRabbit]

There are not file textures related to the material in question, hence there are no filtering options. The noise just comes from reflections off a HDRI and some area lights. It's all fine in other geometry and areas. Maybe it's related to the geometry.... I have to check that

[Darlene_O]

Were you able to solve your problem? I am having the same issues and have tried changing all sorts of settings/numbers.

[Darlene_O]

I spent half my day today playing with settings to get rid of the chrome noise, and finally I found my solution. For my image sampler, I'm using Adaptive DMC, and my anti-aliasing filter I'm using Mitchell-Netravali. In the Adaptive DMC image sampler, I have my Min Subdivs set to 1 and my Max subdivs to 20. 20 was the setting that cleared all of the noise up in my chrome, now everything looks beautiful.

[braveRabbit]

Sorry for the late reply and thanks for the info. I don't quite remember how I worked around the problem. I think I somehow faked it. Next time it happens I will remember your info and give it a shot.

Thanks and Cheers.

[Darlene_O]

The default setting on that Max subdivs is 4 I think? So cranking that up is the magic trick I've found. Changing the sub Ds in the material did nothing for me (even cranking them up to a triple digit # just for kicks). It seems the chrome issue is not a geometry or shader problem, it's an anti-aliasing problem.

Cheers

[Neilg]

I'd suggest it being a filter issue - trying rendering with it turned off.