keen

If you pop over to nukepedia you will find some great 3D tools by these guys. Pintools (great interactive way to position a 3D object in nuke), Geotools (an amazing object tracker that will track your imported 3D object into a live action plate) & ReadRiggedGeo (which allows you to bring in a 3D object rigged to a skeleton & animate/transform/tweak it in nuke). 
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