You can create a magnifying glass effect with any digital video mixer that permits a circle wipe
pattern. Feed your camera’s output into one of your digital mixer’s video inputs. Feed your source VCR’s into another video input.
Next, point your video camera at the monitor that is connected to your source VCR. (This will display your source footage before it enters the mixer). Zoom in on the screen so that it “amplifies” the size of the picture by about 30-40%.
Create a circle wipe pattern with your camera’s signal inside the circle and the actual source footage should be on the outside of the circle. Use the joystick positioner on the video mixer to place the wipe pattern anywhere on the scene that you wish to magnify.
NOTE: To enhance this effect, use a “soft” border around the circle wipe’s edge.