Nuke 3D Tracking, Maya render export motion blur, nuke composite motion blur

how to export motion blur data from maya:
-image sequence
openEXR .exr
-mental ray
-Passes, create scene pass
-2d motion vector (aka mv@DToxik)
-move down / Associated Passes
Done

Import motion blur data to Nuke

-vector blur node

-change UV channel to MV2E...

method to forward

-alpha rgba.alpha

change maya camera to nuke scale
create a locator in maya,
parent the locator with the maya camera,
bake the locate so that it has the transform attribute,
create a new camera,
parent the locator with the new camera
bake the new camera,
delete the locator and you can export that new camera (FBX) to nuke.
next step, import the new camera to nuke
node, new camera,
tick 'read from file'
browse the camera fbx.
DONE