A photographic camera wherein a filter is moved away from the path of incoming scene light in response to attachment of a source of artificial light. The filter is also movable by way of a manually operated selector which can be locked in a position corresponding to inoperative position of the filter. The selector is automatically unlocked in response to attachment of the light source but continues to hold the filter away from the path of incoming light as long as the light source remains attached. A spring returns the filter into the path of incoming light when the light source is detached so that the camera is then ready for making of exposures in daylight.