An image-capturing apparatus for controlling a drive system for an optical system corresponding to the position of an operation unit includes a motor for driving a control target of the drive system, a driver for the motor, position detecting means for detecting the position of the operation unit, position generating means for generating the output corresponding to the position of the operating unit with a limited movable range by configuring an initialization value and maximum and minimum values of integrated displacement by the output of the position detecting means, and controlling means for controlling the motor via the driver so as to drive the control target corresponding to the position generating output of the operating unit.