A second support post is coupled by a vibration isolation mechanism to an upper end of a first support post fixedly mounted in a compartment of a vehicle. Vibrations transmitted from the vehicle while the vehicle is being driven are dampened by a spring of the vibration isolation mechanism, and prevented from being transmitted from the first support post to the second support post. A main unit supported on the second support post for capturing an image of a subject is protected from vibrations from the vehicle. When the vehicle is stopped, the main unit is fixed to the first support post and the vehicle to capture an image of the subject.