How did you do cut-off limbs like in Ryan vs Brandon or Alternate Lightsaber Duel?
In these cases, you will film 2 or 3 things. All of these should be filmed on a tripod, with the camera not moving at all. The first is your action plate, where the actors perform and pretend to loose their limb. The second plate is the background plate (“clean plate”) where the camera should not move at all from the first plate. You want the video to be exactly the same, just without actors. Moving things in the background like cars or trees blowing, etc will not work. The third thing, depending on your shot, can be another action plate for the severed body part’s motion. In the case of RvB, we filmed myself turning around and falling down, trying to emulate the motion I wanted my severed head to have as closely as possible. The next step is the effects. Beginning where you want the limb cut off, you have to rotoscope it carefully. You can then duplicate the layer, and use the bottom one as the main action plate. Set it’s mask to subtract, so that it “removes’ the limb, leaving a hole
