A position indicator is arranged for detecting and indicating the position of a member that is movable along a predetermined path in discrete steps as part of the diaphragm of a still camera. Elements that can produce an electrostatic field and can scan an electrostatic field are alternatively arranged so that a single one of the elements moves with the diaphragm member along a path past a plurality of the other elements positioned along the path. The scanning elements are arranged to operate a switch that can be switched with practically no consumption of power in response to the position of the member, and the switch is arranged to energize at least one indicating element. The electrostatic-field is preferably produced by an electret, the scanning element is preferably an electrode, and the switch is preferably an MOS field-effect transistor.
