Abstract: In an illumination system for a film telecine scanner of the type adapted to provide a line of illumination on the image frames of a film which is supported for rapid movement in a film gate of the scanner, an improved light control system for adjusting the amount of light that is delivered from a light source to an integrating cylinder to take into account fluctuations in intensity of the light source and desired intensity changes in the line of illumination upon a change of scene in the image frames of the film as the film is being scanned. The light control system includes aperture defining apparatus for selectively adjusting the amount of light entering said integrating cylinder in response to the commanded light intensity signal within the time span of scanning a single image frame of the film.

Abstract: A source of illumination of constant color temperature and intensity including a lamp the color temperature of the light from which is dependent on the power applied to the lamp. There is a device for measuring the intensity of portions of the spectrum of the light and for providing signals indicative of those intensities. Means responsive to the signals adjust the power to achieve the selected color temperature. A light modulator adjusts the intensity without affecting color temperature. There is a spherical mirror centered on the lamp and the modulator is located between the lamp and the mirror and controls the brightness of the image of the lamp formed on the lamp by the spherical mirror.

Abstract: There is disclosed a variable brightness light generator embodied in apparatus for exposing photographic film for test purposes. The generator includes a spherical mirror, a lamp at the center of the spherical form of the mirror and a modulator located between the lamp and the mirror for modulating the brightness of the image of the lamp created on the lamp by the mirror. The intensity of the light issuing from the lamp is sensed by a spectroradiometer which produces signals used in controlling the modulator whereby the intensity may be kept constant. The color temperature of the lamp is controlled under the influence of signals from the spectroradiometer. The exposing apparatus also includes a plurality of filters selectively insertable in the light path for modifying the intensity and color of the light incident on the film.