I started this thread on the nVidia Mental Ray Forums (last post). I’ve been tinkering with Unified Sampling for a while. I want to know should I be lowering the samples on my shaders including AO and let Unified Sampling do all the sampling work, or should I keep the samples the same for my Shaders / AO ? I’ve read the ElementalRay article and I’m not able to pull out an answer from this article.
consider unified as a multiplier. you want to find a balance between shader sample settings and the unified setting.
start with lowest shader samples as possible and focus on unified quality value. If its not sampling enough, then first up the quality of the unified, but if you find the unified is sampling more than it should, then dial it back and adjust the shaders samples that need it or else you will over sample with unified.