LC Subdivs value - enforcing a minimum scale size?

[MoonDoggie]

Vlado and Team,
I did some tests with pure LC renders (primary and secondary) to see what kind of coverage I needed for some images. What I found was confusing.

What I expected:
When lowering the sample size and subdivs to very small values, I expected to have black areas in the LC samples where because the sample size was very small (0.01") and the subdivs were very low (250)

What I found:
Sample size appeared to be changed dynamically to make sure full coverage of the image was achieved. Example: 250 subdivs set to size: 0.01" appeared to be scaling the samples up to about 5" (tested by rendering the same scene with 4000 subdivs and size: 5").

What dark magic is going on here? Is VRay changing the sample size on me because of my very low number of subdivs?

-Colin

[vlado]

What dark magic is going on here? Is VRay changing the sample size on me because of my very low number of subdivs?-Colin

The sample size is enforced when calculating the light cache, so that V-Ray knows not to place samples too close to each other. When rendering, V-Ray simply looks for the N nearest samples that it can use.

Best regards,
Vlado

[MoonDoggie]

Also to note: I had fixed set for the sample filtering set to 3x the sample size value, is the above information still correct?

[vlado]

Also to note: I had fixed set for the sample filtering set to 3x the sample size value, is the above information still correct?

With the fixed filtering, if V-Ray can't find a usable sample within the given filter size, it will just look for the nearest one. This is done in order to avoid black artifacts in areas where there might not be enough samples.

Best regards,
Vlado

[Dariusz Makowski (Dadal)]

Interesting info ! Thanks for sharing.