I'm using Twixtor Pro 4.5 demo & I'm trying to slow down a clip which have foreground & background overlapping elements which move in oposite directions. The clip has motion blur in the source.
My question is: what is the best approace to create mattes for the different layers. Should I roto the element and include full motion blur, or should I make a tight matte & leave the motion blur out ?
I would say without seeing that you would make the matte as if the object was not motion blurred. It's hard as Motion Blur means that you have a blending (a semi-transparent foreground). If you have RSMB you might want to see if applying a negative amount like -1 produces a useful intermediate.