Camera system having autofocus function for capturing a moving image

摘要

A camera system includes a camera body (100) and an interchangeable lens (200). The camera body includes an imaging unit that captures a subject image formed by the interchangeable lens in a predetermined capturing cycle to generate image data, a body controller that generates a synchronizing signal having a first cycle correlated with the capturing cycle, and a sending unit that sends the generated synchronizing signal to the interchangeable lens. The body controller further sends information indicating a second cycle different from the first cycle to the interchangeable lens. The interchangeable lens includes a focus lens (230), a drive unit (233) that drives the focus lens along an optical axis, a receiving unit (250) that receives the synchronizing signal and the information indicating the second cycle sent from the camera body, and a lens controller (240) that controls an operation of the interchangeable lens. The lens controller controls the drive unit to perform, in the second cycle, a minute back and forth driving which minutely moves the focus lens back and forth along the optical axis, and performs other control in the first cycle in the interchangeable lens than the control of the minute back and forth driving.