Abstract: Method and photographic apparatus for performing motion studies on a moving subject. The moving subject is photographed through a rotating disc having at least one transparent aperture and a plurality of filter apertures covered with filter plates. Opaque regions of the disc separate the apertures from one another. Preferably, miniature spotlights are connected to moving points of the subject that are desired to be studied. Each of the spotlights projects a beam having essentially one selected wavelength to pass through the filter apertures and the filter plates. Incident background light, lighting the subject, is prevented from passing through the filter apertures by virtue of the filter plates. As a result, a photograph produced by the camera includes a series of light-streak images produced by the motion of the spotlights and the light emitted by the spotlights entering the filter apertures. Interruptions in the light-streaks are produced by the opaque regions of the disc.