1. Video. The effect of a duplicate image that is slightly offset in an analog video transmission. Mismatched impedance in the cables or poor electromagnetic shielding are common causes of this effect in non-broadcast situations. 2. Lighting. Lamp(s) remaining on at a low level even when the control is at zero, or the inability to dim a lamp to completely off. See ghost load and preheat. 3. A followspot operator's method of cheating to find his mark. He/she opens the douser very slightly to see where the beam is. The operator thinks only he can see it, but others often notice. Thus the practice should be discouraged.