A camera has a cartridge chamber lid lock device arranged to allow the camera to be loaded with a film cartridge by opening a cartridge chamber lid irrespective of the position of a lens barrel in the optical axis direction when the film cartridge is not within the cartridge chamber and, when the film cartridge is loaded in the cartridge chamber, to prevent the cartridge chamber lid from being accidentally opened in a case where the film still remains outside the film cartridge or from being inadvertently opened while a using state of the film cartridge is in process of being set.