Sachin Shrestha


About Me

CG Supervisor



Houdini Skills


Not Specified

Recent Forum Posts

Houdini 13 Wishlist. Sept. 15, 2013, 2:31 a.m.

Sorry if i'm repeating, but:
1. More sophisticated shutter model (like one in prman)

You just want prman's shutteropening(opentime, closetime, optional spline points)?

Yes, exactly. I would be happy to have that in mantra.


We have had to resort to comp hacks to match hold outs from prman and mantra so this would be an important feature to add. And while at it, perhaps even provide a method to visualise the spline using a ramp as shown in the prman docs (something that even RMS lacks).

Integer Frame Motion Blur July 1, 2013, 2:28 p.m.

Hi Rob,

I did think of the DCM workflow but never got around to trying it. Does Nuke support rat files out of the box now or do I have to use rat4nuke? Do you have any tips or resources that can help me explore this workflow?

Integer Frame Motion Blur June 30, 2013, 3:43 p.m.

Great to have Peter Quint reply to my first post! Thank you for the invaluable lessons on your Vimeo page.

Apologies if I wasn't clear enough. I debugged the issue by exporting a rib from Houdini and found that for “Trailing Blur” at Shutter Time 1 and for frame, say, 110 it was exporting the motion data from frame 110 to 110.5 (I cross verified by manually moving the frame ticker to 110.5 and the transformation values matched with what was exported). I tried various permutations but Houdini always seemed to sample at fractional frames instead of exporting from 110 to 111.

The equivalent settings in Maya/RMS are Shutter Angle of 360 (for shutter time as 0-1), Frame Open and sampling at “Frame” instead of “Subframe”. That samples shutter open at 110 and close at 111. If I switch to Subframe then the RMS render matches Houdini's. So I think Houdini is always sampling subframe motion blur.