Does anyone know why things like this (the noise) appear while rendering glossy reflections? I wanted to render some clean scenes with realistic specular lighting but it seems that it’s harder than I initially thought it should be.
There’s a very large warning attached to this website. Please be sure you want to take the risk before downloading anything from here. No offense to the original poster intended. This has been reported as a malware site.
That’s a difficult lighting situation to solve for. Make sure multiple importance sampling is on for your lights, and increase your samples.
I’m not using Cycles, this is rendered with the default renderer. And I’m already maxed out on sample count there (1024 samples). Surely there should be a much better result with such sample count?
P.S. Those aren’t technically lights, just emissive surfaces.
Thanks for the warning. Not very concerned about malware but I’m not going to bother checking that site. It’s possible to attach a .blend file in here and http://www.pasteall.org/blend/ works too.
I don’t see a malware warning or have ever seen that or any suspicious behavior for that website. Since I can’t fix the horrible AV software, I added a download mirror: http://www.pasteall.org/blend/25113
Looking at this… (and i am darn suspicious against MW warnings - this one looks like competition or some ria/drm composed threat; from where the warning came from btw?)…
I see this:
Warning came from Comodo. Rarely get warnings from them unlike other AV/AMW. Just thought I would mention it. Thanks for the mirror.
I wonder if you are referring to the roughness of the reflection as noise which it looks like. That is to simulate a ‘noisy’ rough surface as opposed to a smooth glossy one so it’s no surprise it looks like noise. Turning up the samples may smooth it out a bit. There’s noway to have anisotropic reflections and a perfectly glossy surface though.
I don’t find anything in the material settings that would make the surface rough (like texture maps affecting normals, which is the usual way to get something to look rough). This is supposed to be a perfectly smooth glossy reflection, which is why the noise seems odd here. Also, in areas with less contrast there seems to be much less noise, which is why I don’t find it looking like an effect of any kind.
It seems like the smaller a reflected object is, the more noise there is around it.
Look under mirror, see where you have reduced the gloss setting to less than 1? Without this the anisotropic won’t work. With it you get simulated surface roughness.
The size of the reflected object decides the size of the reflection. The gloss setting decides the size of the rough area. A large object will therefore have a relatively smaller fringe; a small object will appear to have a fringe closer to its size. Sorry if this is not clear!
I know how it works, I just want to fully understand reduce the noise without blowing render times up in the sky. But I guess raytracing isn’t going to give me what I want.
P.S. Gloss isn’t always about roughness. It might be (with different kinds of glass) and it also might not be (wooden floor and things like that: http://internationalfallsmn.us/wp-content/uploads/2013/10/Hardwood-floor-pads.jpg)