In a camera system, a lens CPU controls the operation of an interchangeable lens at a control instruction from a camera body. In the camera body, a subject formed on an imaging element by using the interchangeable lens is photographed at a specified frame rate and image data is generated. A camera body communication circuit transmits a timing signal in accordance with the frame rate to the lens CPU through a main body CPU. The main body CPU acquires lens characteristic data stored in non-volatile memory by a communication with the lens CPU, determines the transmission period of the timing signal according to the acquired lens characteristic data, and controls the camera body communication circuit on the basis of the determined transmission period.