Cinema News and Property Gazette Technical Supplement (1924-1925, 1943, 1946)

16 Supplement to THE CINEMA NEWS AND PEOPEETT GAZETTE. November 26, 192 = OPERATOR S CORNER. There are some fellows who are never at a loss for an excuse wherewith to cover up their own shortcomings. I was told by an assistant — who had been at the game long enough to know better — when I pointed out to him the jerkiness of his projection, that " it must be the screen wobbling." That same assistant had a mortal antipathy to keeping the lenses and projection port glasses optically clean. So long as he just wiped them over — even with an oily rag — he considered his duty done nobly and well. I wonder how many of us realise the prime importance of looking to this point? One of the chief things we have to concern ourselves about, if we are to get the best out of our apparatus, is to get every possible unit of illumination through to the screen via the film-gate ; and that can only be done — all other things being correct — by getting maximum optical clarity in lenses and other glasses through which the rays must pass. Personally, I would as soon think of starting my show without first burmng in my craters as I would without polishing lenses and port-glasses. Moreover, I have always an old silk handkerchief at hand in order to give the glasses a rub after each change-over ; for it is simply surprising how quickly the smoke and moisture of the atmosphere in the auditorium causes a white film to form on the port-glasses, and the consequent absorption of light may not seem serious, but it is material. One generally looks at condensers each time the arc is struck, but the objective lenses get overlooked — sometimes for weeks on end. It is an excellent plan to take them out at the end of each performance and keep them in a leather bag or lined box during the night ; indeed, where highgrade and expensive large-aperture lenses are used, this should be regarded as an essential safeguard. Chief Operator. nates eye strain considerably. The glass is held in position by two thin strips of metal soldered to frame. — VVilf. S. Owens, New Garden Cinema, Bewdley, Worcs. IMPBOVED INDICATOR FOB MIBBOB ABC LAMPS. The attachment referred to in last month's " Operators' Corner " as being fitted to the Hahn-Goerz Projector for the purpose of throwing an image of the arc (—J LAMP BOX WHITE PLATE FOR THE KALEE. In the accompanying diagrams is an improvement in Mr. J. R. Mackellar's frame device to minimise fire risk (published in The Cinema dated October 29). Mr. Mackellar's idea is good, but would be useless on my machine (" Kalee Indomitable "), unless fixed to the aperture plate. Of course, when the picture becomes out of mask the rays would be thrown off centre of frame. There are a good many of these machines in use, and METAL FRAME m&'scflHK fSSrO SCR£>Y APERTURE PLATE Of "XALEE " these diagrams show how frame can be easily fitted to two screws (A and B) on aperture plate. A hole cut out of centre of frame and coloured glass fixed in elimi on the ceiling or any other convenient place so as to observe the condition of the crater, is well known to users of the Simplex Machine, and has been fitted at times to several other makes. Although its use for observing the condition and, perhaps, length of the arc without risk of glare or strain on the operator's eyes has an advantage, yet a very important point, namely, the keeping of the arc at its correct distance from the centre of the mirror, cannot be checked easily by its use. An improved attachment of this type was devised and built by the writer some year or so ago, in which the image of the arc and carbons, instead of being projected upon the ceiling or wall, is thrown down upon a whitened plate attached to the edge of the lantern box. Having found by experiment the very best position for maximum light, the outline of the carbons was traced out in black ink upon this white plate, so that it is possible, practically instantaneously, to adjust the carbons to this position; in fact, by its aid an absolute novice has no difficulty at all in getting a perfectly illuminated screen. The diagram shows very clearly the arrangement. I am asking you to publish this in the hope that it may be of use to operators using mirror arcs, and as this is not patented or protected in any way, anyone is free to use it. — A. S. Cubttt, The Rectoscope Company, 203, Shaftesbury Avenue, W.C. 1.