Bercon metaballs, water and motion blur problems

[jay_vortex]

Hey everyone,

im sorry if this as been posted before i searched and found nothing and got to admit im in a hurry...!!

So here's the problem:

I got some water streams that i did with particle flow and i meshed them with the berconmetaballs.

Works great, the only problem is when i put 3d motion blur, the render will build its light cache for eternity, or the light cache will be fast but the last irradiance bucket will take ages to finish.

Also when i press cancel it does'nt work, i always have to kill max.

Really stuck here!!!

My idea was to do the MB in post with RSMB but i cant seem to get the velocity pass to show something in it...??

EDIT: Btw, i started to have problem when i upped the particles birth count, to 200 000. But i need that to get the effect, and i dont think its that much?? Im new to particle flow so nothing to refer to.

Thx!

Jay.

[jay_vortex]

Alright, so think i've found the solution. From a post Vlado made on cgtalk actually.

I upped the geometric samples to 10 instead of the default of 2, in the vray:camera / motion blur panel.

What i THINK it does is if Vray is not able to calculate the motion blur between two frames, because lets say the meshs go too fast then he will calculate more until he knows exactly how to blur the meshs.

Then i guess the irradiance or light cache whatever is able to light it properly.

Thats the way i see it...but i could be way wrong so if maybe Vlado could shed some light on this, that would be great.

Thx!

Jay.