So that parallax-free images can be taken even if the camera is rotated during filming and the direction of the camera is changed to an arbitrary direction, the auxiliary device is provided with a camera body retaining part and, in an equidistant surface centered on the nodal point of the camera, a camera attachment part. Regardless of the angle the camera makes as a result of the way in which the camera attachment part is mounted to a camera support mechanism part, the nodal point of the camera remains at a fixed location.