Abstract: A focusing system for a variable focus lens of a motion picture camera includes a pulse modulator and a microwave transmitter mounted on a camera frame for generating a high frequency pulsed signal which is transmitted to a selected target which carries a reactive signal generator that is responsive to the first signal for coding and retransmitting the coded signal back to a receiver mounted on the camera frame, and a signal processor for determining the interval of travel of the signal and translating the interval into a distance-analog signal that is transmitted to a focusing motor for driving the focusing mechanism of the lens for focusing the lens at the distance determined by the signal. One alternate embodiment includes multiple reactive signal generators having distinctive signal responsive controls and portable remote transmitters for selectively switching to the selected ones of said reactive generators.