The control unit sets up the center and an insensitive zone of a zoom seesaw switch provided in a drive unit of an ENG lens by an electrical processing. The control unit is capable of dispensing with a mechanical adjustment of the center and the insensitive zone of the zoom seesaw switch in assembling the product, and the assembly of the product is thus simplified. On turning on a center setting switch while the zoom seesaw switch is released from the operation, an operational position of the zoom seesaw switch at that time is accurately set as the center that brings the moving rapidity of the zoom lens to zero. On setting an insensitive zone size by an insensitive zone setup device, the moving rapidity of the zoom lens becomes zero whenever the operational position of the zoom seesaw switch is within the insensitive zone. Any of these settings is carried out by a processing of a CPU.