An optical system for transmitting light from an object in a dual field of view, the system comprising optical elements providing alternate optical paths associated with each of a wide and a narrow field of view, at least a portion of the optical paths being in alignment, there being disposed within the aligned portion of the optical paths a blocking element selectably operable to enable passage of the light from the object which is associated with one of the alternate optical paths while simultaneously blocking passage of the light associated with the other alternate optical path.