Proceedings PaperPractical method for optically reducing holographic images
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It was our intention to develop methods for reducing the real image pseudoscopic projection from a laser illuminated pulsed transmission master hologram during the transfer process for the recording of second generation white light viewable reflection copy holograms. The coherence volume of our 10 joule ruby laser is approximately 1.5 cubic meters per pulse, resulting in deep scene holographic recordings of human subjects including props and backdrops. The vibration isolation optical bench used in our lab for the transfer process is only 4 X 8 feet which limits the size of the holograms produced to 32 X 43 cm or smaller. Much of the information contained in our master holograms fell outside the boundaries of medium format holographic film or plates, usually limiting holograms of live subjects to head and shoulder portraits. The introduction of a plano-convex lens between the master and the copy hologram in a typical reflection hologram recording configuration reduced the size of the real image projected from the master onto the copy hologram, allowing us to record full figure compositions on film as small as 4 X 5 inches. The size and focal lengths of the various lenses used, the recording geometries, and the developing chemistry used to achieve acceptable skin tones are discussed and illustrated.