The Cine Technician (1953-1956)

November, 1953 THE CINE-TECHNICIAN 147 (1) Two telescopes mounted parallel to optical axis of lenses for accurate convergence. (2) Two factory matched Wollensak Cine Raptar lenses, F.L. 40mm., speed f/1.5. (3) Two interlock gears. (4) Flexible shaft driving interlock gears. (5) Scale for interaxial setting. (6) Bodine sync, motor, 1.440 F.P.S., 115 volt, 60 cycle, A.C. (7) Two factory matched Wollensak Cine Raptar lenses, F.L. 25mm., speed f/1.5. (8) Centre line telescope. (9) Interaxial adjustment 2\ to 4i inches. (10) Micrometer convergence adjustment infinity to 4 feet. (11) Zoom type finder 15mm. to 150mm. (12) Zoom type parallax adjustment. From the producer's point of view the importance of the tricolor matrix material lies in its application to the making of release prints, particularly for overseas distribution. A Hollywood producer, for example, who has photographed a film on Eastman colour negative, irrespective of the way he makes prints for home distribution, needs only to send the colour negative to Technicolor where the necessary matrices can be quickly made. The matrices are shipped to London, where the prints for European distribution can be made at maximum speed and minimum cost. By the use of Eastman colour negative a production company benefits in several ways — high emulsion speed, automatic masking which gives quality virtually as good as a three-strip camera, and the choice of either low cost, good quality imbibition prints, or slightly higher cost prints with adequate definition for wide screen projection. The current process used by Technicolor for producing travelling mattes is described by Ashton in the same article. The details have been disclosed in two recently granted British patents. The background action is photographed with a three-strip camera (monopack may be used with a little more complication). The foreground action is photographed in front of a coloured backing, or a white backing and illuminated with coloured light. The actors in the foreground are lit in the normal way with white light. The backing is lit so that it will record as a maximum density on either the green record or the blue record film of the three-strip camera. For example, a white backing is lit by mercury vapour lamps with yellow filters so that the illumination is principally from the two green spectral lines at 548 and 577 mu. Alternatively, blue filters may be used on the lamps to utilise the blue spectral lines of the mercury lamp at 404.6 mu and 436 mu. The effect of this is to give three normal separation negatives as far as the actors are concerned, but the backing records as a high density on one of the three films, either the blue sensitive or the green sensitive, and as a low density on the other two. One of the films with the low density backing is used together with a print from the negative showing the backing as a high density to produce three matte films on high-contrast sensitive material. After development, these three films will show absolutely clear celluloid in the portions of the picture area occupied by the actors, and a high density everywhere else. Then, in making a set of master positives of the background action, one of the matte films may be used to completely fog the foreground action area. The other two are used to hold the background action area unexposed when the foreground action is being printed on the duplicate negative. The film which is used to matte the master positives is different from those used to provide the matte for the duplicate negative in that it is made on regular master positive film such as Eastman 5365. This is done so that bad register of the final images due to spread or image growth is cancelled since it will occur twice in opposite directions, once in the matte and again in the background masters. The mattes which are used in printing the duplicate negatives from the foreground masters are made in the normal way on high-contrast material such as Eastman 1363. This 3-D camera is the brain child of Eddie Linden. He uses two De Vry's, mounted on a one-foot square plate. Both cameras can be operated with one Mitchell wild motor. The camera has convergence adjustment and the interocular is adjustable from two to five inches. It has matched Cooke lenses and will take 400 or 1,000-foot magazines.