incorrect motion blur on a moving train abc in redshift

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I have a train alembic exported from maya to houdini and rendering redshift, There is a camera attached to the train carriage (parented inside Maya) which is exported as alembic as well. In houdini I'm doing general clean operations, converting to polygons and caching as bgeo with point velocity calculation. When i render the bgeo i'm getting incorrect motion blur spikes in certain frames which is really hard to fix at this point.
I generated acceleration attribute from point vel and i noticed huge jumps in certain frames like 120 to -700 even though mesh is perfectly smooth.
The ideal way is that the mesh should be without motion blur (cam attached to it) and landscape full blur. It is working as expected for most frames except some. (attached video)
I have ticked mesh deformation blur from velocity on in obj container of train carriage, without it the train is in streaks like env.

I'm in dire need of help as deadline is approaching. kindly help please.

Attachments:
djv_D7MmUNHIK9.mp4 (2.3 MB)

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Are you doing your velocity calculations before or after the clean up? If "after", try switching it to "before" clean up.
The clean up might be changing the topology of the mesh and causing the velocity spikes.

Cheers,
Toronto - ON
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“As technology advances, the rendering time remains constant.”
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You could also do you velocity calculation on the original mesh and attribute transfer to the clean mesh, in the worst case scenario...
Toronto - ON
My Houdini playground [renderfarm.tumblr.com]
“As technology advances, the rendering time remains constant.”
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I'm not sure if redshift does Xform MBlur for transforming packed primitives, but if it does that may be the best type of MB you can get for rigidly moving objects
as that would give you also more proper angular MB for wheels etc

you can test it directly on your transforming packed alembic primitives and if it works you can do your cleanup at rest space and then just pack and transform each object back with the original prims or pack inject into them
Tomas Slancik
FX Supervisor
Method Studios, NY
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Thanks guys, I think you guys have given plenty of good ideas which I haven't tried yet. I will try these.
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