Abstract: In a mounting device for mounting a flashlight unit to a camera body with coupling established between a base secured to the camera body and a base secured to the flashlight unit, one of the two bases has a protrusion and the other base includes a recess for receiving the protrusion therein, a restraining member having a restraining position for restraining the protrusion and a nonrestraining position for releasing the protrusion, a biasing member biased to retain the restraining member in its nonrestraining position when it is in such position but adapted to release the restraining member upon coupling of the two bases to permit the restraining member to move to its restraining position, a first release member for bringing the restraining member to its nonrestraining position, and a second release member for preventing the restraining member from being moved to its nonrestraining position by the first release member.

Abstract: In a film projector of the type wherein film advance is controlled by pulse signals generated by a tape recorder or the like, a protective filter is automatically inserted into the optical path between the projection lamp and the film when the time interval between successive pulse signals exceeds a predetermined time limit. The filter is automatically removed from the optical path only when two successive time intervals have a duration less than a predetermined duration.