British Kinematography (1950)

101 BRITISH KINEMATOGRAPHY Vol. 17, No. 6 By courtesy of Mr. G. Wynne, of the C.W.S. Film Section, Manchester, a Newall camera and G.E.C. lighting equipment were demonstrated by Mr. H. S. Hampson. REFERENCES 1. Brit. Kine., 14, No. 1, Jan. 1949, p. 1. 9. Brit. Kine., 14, No. 1, Jan. 1949, p. 7. 2. Brit. Kinc, 15, No. 5, Nov. 1949, p. 141. 10. Proc. B.K.S., No. 16 (1933); J.Brit. 3. Brit. Kine., 14, No. 6, June 1949, p. 185. Kine. Soc, 2, No. 3, July 1939, p. 143. 4. J. Soc. Mot. Pic. Eng., 54, No. 3, 11. Brit. Kine., 17, No. 4, Oct. 1950, p. 109. Mar. 1950, p. 290. 12. J. Soc. Mot. Pic. and Tel. Eng., 52, 5. Brit. Kine., 16, No. 5, May 1950, p. 156. No. 4, Apr. 1950, p. 447. 6. J. Soc. Mot. Pic. Eng., 53, No. 5, 13. Brit. Kine., 12, No. 4, Apr. 1948, Nov. 1949 ; 55, No. 2, Aug. 1950, p. 158. p. J09. 7. Brit. Kine., 16, No. 2, Feb. 1950, p. 38. 14. /. Soc. Mot. Pic. and Tel. Eng., 54, 8. Brit. Kine., 17, No. 1, July 1950, p. 5. No. 1, Jan. 1950, p. 95. TECHNICAL ABSTRACTS Most of the periodicals here abstracted may be seen in the Society s Library COLOUR DEVELOPMENT IN THE PRESENCE OF COLOURED COUPLERS R. Merckx, Science et lnd. Phot., Mar. 1950, p. 84. Fourteen new dyes have been examined in colour development with NNj-diethyl-pphenylene-diamine. The presence of a nitrile group attached to the C in the chain = C = N — appears to be essential for the formation of an azomethine dye. G. I. P. L. OBTAINING COLOURED PHOTOGRAPHIC IMAGES BY ELECTROLYSIS OR ELECTRO-SYNTHESIS J. Rzymbowski, Science et lnd. Phot., Mar. 1950, p. 86. The cathodic reduction of a mixture of phenol with nitrothymol or nitrocresol gives the reduced form of an indophenol which constitutes the developer. In development the insoluble oxidised form of the indophenol is deposited with the silver image and remains as an intense blue dye image when the silver is removed. G. I. P. L. CATADIOPTRIC OBJECTIVES M. Paul, Science et lnd. Phot., Mar. 1950, p. 81. A review is given of catadioptric, i.e. reflection-refraction, objectives such as the Schmidt system. G. I. P. L. A NEW //1. 5 LENS FOR PROFESSIONAL 16-MM. PROJECTION W. E. Shade, J. Soc. Mot. Pic. and Telex. Eng., Mar. 1950, p. 337. The historical development of Petzval type projection lenses, incorporating a field flattening element near the focal plane, is outlined. The progressive improvements in aberration correction and performance are described, comparative data being given for a new series of //1.5 lenses of this type announced by the Eastman Kodak Co. Improvements in resolving power, contrast and back focus are claimed. A. H. A. A MOTION REPEATING SYSTEM FOR SPECIAL EFFECT PHOTOGRAPHY O. L. Dupy, J. Soc. Mot. Pic. and Telex. Eng., Mar. 1950, p. 290. Tilting and panning movements of a camera head are recorded in the form of tracks on a disc. To reproduce the movements, the amplified signals are caused to operate a differential drive system controlling the camera movement. R. H. C. INCREASED NOISE REDUCTION BY DELAY NETWORKS J. Soc. Mot. Pic. and Telex. Eng., Mar. 1950, p. 295. The signal applied to the modulator of a photographic sound recorder is delayed with respect to that applied to the noise reduction circuit. This is accomplished by means of a series of four delay networks, giving a total of 14 milliseconds delay over a wide frequency range with very low distortion. With this set-up, margin settkg may be reduced to zero, and noise reduction values as high as 30 db obtained without audible distortion. N. L.