The processing of steps S701 to S705 is the same as in the second embodiment, and will therefore not be described here. After the focus guide display processing for the right image in step S705 is complete, in step S1106, the system control unit 218 determines whether to display the difference in the degree of focus between the left and right images.
Whether to display the difference in the degree of focus between the left and right images may, for example, be an item set by the user, or may be determined by the system control unit 218 according to the operating mode of the camera 100. For example, if a moving image mode of the camera 100 is set to an adjustment mode for the user to adjust the difference in the degree of focus between the imaging optical systems of the binocular lens unit 300, the system control unit 218 determines that the difference in the degree of focus between the left and right images is to be displayed. In the adjustment mode, the user can adjust the focus distances of the right eye optical system 301R and the left eye optical system 301L by, for example, operating individual focus rings, in order to eliminate differences between the focus distances of the right eye optical system 301R and the left eye optical system 301L.
The system control unit 218 executes step S1107 if it is determined that the difference in the degree of focus between the left and right images is to be displayed, and executes step S706 if not.