relationship between noise limit and samples limit in NEXT GPU ?

[Subburb]

Hello ! I'm trying to calibrate SolidRocks for NExt GPU and i'm puzzled while observing results when tweaking noise limit and samples limit. i can't figure cleary how they are tied together..
Would you please explain a bit ?
Thanks in advance !

[radoslav.platikanov]

Hello!

They're two separate limits that are both applied to each pixel. During rendering the pixels are regularly checked and if at least one of the limits is reached for a pixel, it's not sampled anymore.
They work pretty much the same as in V-Ray CPU, the only difference is that the samples limit in V-Ray is set in subdivs (the actual number of samples is the square of the subdivs).
The sample rate render element can be very useful for seeing what's going on with the sampling.

https://docs.chaosgroup.com/display/...ngs-Parameters
https://docs.chaosgroup.com/display/...VRaySampleRate

[Subburb]

Wow ! Many thanks for fast and clear explanation. So if i start with 1250 samples and 0.011 noise thr for medium quality, 5000 and 0.002 for production, 9000 and 0.001 for ultra quality, i'm good ?

[radoslav.platikanov]

Should be fine, yes. The noise threshold is the main quality control so it's easy to find good values. The optimal samples limit varies quite a lot from scene to scene and a preset won't be always perfect but it should be fine if it's not too small or too large.