Problems with motion blur

[Ivan1982]

Hello,

Heaving big troubles with motion blur.

Long story short things are like this, currently working on some liquid simulations, i can't make vrmesh generated from phoenix(demo) to render motion blur.

I had cached Particles, Frost and various other moving objects with deforming topology with xmesh and rayfire and converted all that to vrmesh and motion blur worked. So i know vrmesh is capable of producing MB.

When i create simulation, thick all possible velocity channels ON(before simulation of course) and convert that to vrmesh and load again from whatever reason i can't get MB to render. Of course MB works fine when rendering phoenix.

Tried everything i could think of, even cached from phoenix to xmesh>vrmesh>rayfire back to vrmesh can't get it to work.

This is not scene related, as i have tested it with simplest scene possible emitter and phoenix Liquid.

Using Physical cam global exposure duration 1/60s.

Take care

[Ivan1982]

I managed to get some motion blur...

This is small example, problem is that vrmesh motion blur seems to reference pivot point of the vrmesh, that pivot point is inherited from phoenixFD liquidSIM, there is velocity channel.

What could cause this?

[Ivan1982]

Found workaround.

[svetlozar.draganov]

Would it be possible to attach both scenes, the ones with Phoenix simulation and the other one with V-Ray mesh for investigation.
A little information about the workaround would be also very helpful.

Let us know the exact versions of Phoenix FD, V-Ray and 3dsMax.

[Ivan1982]

Hello, problem was modifying topology, from whatever reason, something about incorrect number of vertices between frames. Searched online for solutions and i got that info from ephere forum(something about LUCID and MB in Vray) but it sounded so familiar and didn't have time to investigate any further.
In second post is example without cut, just vrmesh export, that produces wrong motion blur(based around object pivot).
Work around was to setup scene, use phoenix sim we got, pray, not save and render and pray we wouldn't have to render again we weren't able to achieve exactly same results as we wanted, but it wasn't noticeable at the end. Anyway it was only solution at the moment.
Tried with frost and particles(we used that for other things) and results wasn't satisfactory for liquid. Xmeshing, rayfire cache also wasn't able to produce any motion blur when phoenix was used on vrmesh. Absolutely every velocity channel was saved in phoenix but it didn't yield results.
If we used rayfire slicer on any vrmesh it wasn't able to produce MB, that is why i asked few days earlier will vray clipper be supported on GPU.

Using Thinkbox Frost and particles for other liquids with rayfire cache and xmesh was able to produce proper mblur on vrmesh(without cutting) just fine.
Vray was NB from 25th October, tried with few NB around oct/nov, Max was 2016 sp3 and phoenix was 3, we used demo 3 for loading it, so i guess that files are from version 3?
We deleted those files as they were already rendered.
Here are some shots.

First is ray fire slice(doesn't need MB as it is slow moving, well it needs but it is ok without) Second had to have MB(that is what was making problems) Third is FROST and vrmesh and it has MB, it is slow motion transitioning in real time(can't fake MB in Post).