Bucket sample error

[ior=0]

The images shows I'm getting different sample rates in different buckets. The buckets are all from the same machine and in the similar place on the model.
I've tried changing sequence to see if it is random buckets but I don't think it is.
What is weird is that some adjacent buckets, same object, same material get a different better sample rates.

I can't show the whole image cos NDA but it is not working well in animations!!!

I've attached 2 images where I moved the camera slightly to better show that it isn't intrinsically related to a specific part of the model, but seems more bucket related,as adjacent buckets are doing totally different things
The sampler is set to 1/48 with a threshold of 0.005
Brute force / light cache (
Some help would be really useful as a deadline is looming and this is really going to ruin my day!
thanks

[yavor.rubenov]

Hello,

Any change if you set the sampler minimum subdivs to a higher value like 2 or even 3 ?

Best regards,
Yavor

[psanitra]

Maybe cutoffs on light and or materials, might happen if you have darker scene. Try to set lights cutoff to 0. I also saw this happening in adaptive vray domelight(experimental feature), but i guess that only apply to Next version..

[ior=0]

I think I found the problem. The scene was very dark, lit by one bright max spot (rim light effect), but if I turned on the dome HDR to just 0.01 (no discernible effect of the visible lighting) I was using for the fully lit scene the sample rate was fixed. What was really throwing me was that some buckets did and some didn't. Yavor - I'll try the min subdivs see if that effects it too.

[ior=0]

Yavor - I increased the min subdiv to 3 and then 8 got more bucket with samples but still some without, why would some buckets just not sample? Obviously the scene could do with more samples in the dark, but those area are basically black. It's the inconsistency that causes the problem by adding obvious blocks of additional noise that is very obvious in animation as they glitch. But I'm relieved to have sorted it by adding a bit of global HDR light

[psanitra]

yeah, max spotlights with vray shadow does not have a light cuttoff control exposed so that`s an issue. Having to add additional dome light that`s pretty bad solution. I wish devs could fix this and expose the cuttoff control on default(max lights). You can try to relight your scene with targeted vray light and high directionality, set cuttoff to 0 and it will work fine.