High shutter speed, high frame rate, 20% overscan.
Methods in order from simple to expensive.
Method 1:
locked off camera, shoot 2 passes, freeze frame one pass, and rotoscope the other layer over the top
Method 2:
locked off camera, shoot 2 passes, freeze frame one pass, and rotoscope the other layer over the top, add handheld camera transformation over the top.
Method 3:
steadicam rig, shoot only 1 pass, cut to actors acting as if they are frozen with interacting actor included, roto and clean up steadywires and eye blinking. 3d track and add in 3D elements, add rotoscope motion blur over "frozen" actors to differentiate them from the background. add handheld camera movement over final shot. cut to different angle before unfreezing actors. tracking markers needed.
Method 4: 2D method √
in short...
treat your frozen actors as if they are 2D card objects i.e. shoot texture plate of each frozen object, then reproject them back on a 2D card that is tracked back unto the "realtime actor" plate.
Method 5: √√√√
motion controlled camera: shoot a layer of realtime actor, shoot layer of "actors frozen" with sped up motion controlled camera movement by 4 and film speed by 4. Slow this camera back to realtime, do clean ups, add rotoscoped "realtime actor". add 3D elements. The lighting is gonna be the tricky bit and preferably a greenscreen behind the "realtime actor" or else lots of roto. tracking markers needed or else movement data from motion controlled camera.
Method 6: 3D method, complicated
in short...
treat your frozen actors as if they are 3D objects i.e. shoot texture plate of each frozen object, then reproject them back on a 3D mesh that is 3D tracked back unto the "realtime actor" plate.
