To photograph a subject in size by which the subject can be identified even though a distance to a monitoring range is long while securing a wide photographic viewing angle.

A holding tool 22 for holding two film units with a lens 18 and 19 is provided inside a case. The holding tool 22 is constituted of a pair of holding members and a coupling part for coupling the holding members. Either holding member holds one side surface of either film unit 18. The other holding member holds the other side surface of the other film unit 19. The coupling part couples a pair of holding members so that the photographic optical axes 18a and 19a of the two film units 18 and 19 may be adjusted to form a specified angle.