Kinematograph year book (1944)

280 The Kinematograph Year Book. baths constant and adjusting voltages ; he also referred to the unreliability of a visual type of desensitometer and recommended an instrument embodying a sodium or potassium cell. Recent developments, in the view of John Ojerholm, of Olympic, indicate that the Industry has passed through a major revolution of method. The closer application of photographic sensitometer to raw stock by the manufacturers, the use by the cameraman of a meter to get the maximum from the stock, and, finally, the laboratory's scientific methods are the three components of control. When the war is over there will be a big step forward in technique, particularly as a result of fine grain printing and of various colour processes on which the laboratories have been working. In the U.S., at the present moment, experiments on fine grain stock with the resulting modification of formulae, on new types of printing machines and the use of mercury vapour are forging ahead. Meanwhile, as we wait for those further developments we shall not be wasting our time by co-operating to exploit the benefits of control for the sake of improved results on the screen. Film printers have been overwhelmed with work during the past year and it is to the credit of the efficiency of their organisation which nowadays has largely to depend on previously untrained women that so consistent a quality has been maintained alongside greatly increased output arising from the Government work on top of the usual Trade demand. The full effects of the rationing scheme was not felt until the latter six-month peiiod of 1944 because the old London distribution scheme upon which copies were ordered was not replaced by the three-area arrangement until May. It says much, too, for the country's supply situation and, incidentally, perhaps the soundness of peace-time formulas that at Denham, for instance, not a single change has been made since the war in their chemical formulae by the employment of substitutes. One of the difficulties faced by laboratories is the shortage of tinplate, and nowadays much of the film circulates through the plant in strong paper bags until it is finally packed in cans. The cut of 25 per cent, in the amount of raw stock available for commercial entertainment has given a fresh impetus to the perfecting of various preservation and regeneration processes, the latter of which has' proved of the greatest value in respect to the distribution of re-issues. The use of the various hardening systems available has certainly proved effective in the prolongation of the life of the prints ; and if this precaution has not altogether attained its objective, the fault lies not with the treated film but with the deplorable handling of the film in the course of its presentation runs. Much has been done by the technical staff of Denham laboratories during the year in research and experiments on the preservation and regeneration of film. Denham's Regeneration Plant has been responsible for saving many millions of feet of film which normally would have been useless for showing. The recently introduced " Olympax " film treatment sponsored by John Ojerholm, of Olympic Kine Laboratories, has fully justified the early claims made for the process which comprises a method of chemically seasoning the gelatine, which is thus rendered impervious to scratches. Shrinkage or swelling arising from the heat of the projector illuminant is also prevented. This processing or coating method is universally used in America, being applied to the film at the laboratory at the time of printing and has proved effective in reducing damage and imparting maximum efficiency. In this connection interesting facts concerning the preservation of film in its National Library are given by the British Film Institute. In July, 1942, some early films examined were discovered to be in a sticky condition. The Research Department of Kodak reported that the condition was due to aisintegration of the support, which made the emulsion strongly acid. In the presence of moisture the emulsion liquefied, and nitric acid could be detected. The discovery emphasised tne desirability of chemical examination so as to detect the approach of disinte juration in advance, so that the films in which it appeared could be copied in time to preveni their loss. This was