motion vector from Maya render pass

Motion Vectors - Example II from Sagroth on Vimeo.

And the Sigillarium Blog

Quick note:

1: Add a "Normalized 2d motion vector" pass in render setting, and set normalized 2d motion vector > Render Pass Parameters > Max Pixel Diap. (your render images width size, but 1024 is max), Filter is ON!

2: In render setting > Motion Blur > Motion offset to 0

3: render quality is 4x32bit float!