Hasta La Motion!

Hi gang, I’ve got a maya-houdini workflow problem. I’m basically lighting, shading, animating and rendering all geometry within maya using MR, and I’m transferring all that geo to houdini for all dynamic effects such as particles, fluids and rbd’s. I’m having a motion blur issue within houdini.

I basically got dust particles coming off the ground under a moving object so I have some particles behind, to the side and in front of the moving object. During rendertime, I’m using the moving object as a matte for the particles just so I dont have to render stuff that is not going to appear in the final render and I’m also setting the motion blur settings I used in maya for the moving object so my object matte has the same motion blur so everything lays down nicely later in nuke.

I noticed that the motion blurred object matte on the particles render does not match the motion blurred object once I composite it. Settings are exactly the same as in mental ray , but it just isn’t lining up..tried different setting settings and testing the comp and still not getting something decent….I’m sure it is an issue of the motion blur algorithm on the renderers….any ideas how this problem can be tackled? BTW…this was my VFX 401 challenge entry that I never finished haha….thought I might as well get it done.