International photographer (Feb-Dec 1929)

Eight The INTERNATIONAL PHOTOGRAPHER December, 1929 The Densometer an Automatic Timer •BY' THE EDITOR 4 An announcement of considerable importance to the Motion Picture Technical workers is made by the Technical Research Manufacturing Corporation, an organization devoted to the research of problems encountered in the photographing, developing and projection of pictures from the film where the light element has played such an erratic part. The technicians of this company need no introduction to the studio end of the picture business, as Mr. Lewis W Physioc's long years of experience with the artistic as well as the scientific avenues of the industry, coupled with the research ability of Mr. Delmar A. Whitson, whose pioneer experiments with the sound-track application covering a period of over fifteen years, have produced a team of no small ability and recognition. The Densometer, which is the subject matter of this announcement, is the refined product of several prior models which were developed to eliminate the human element of judgment where the averaging of film density is now required, and for saving the extra time and materrial to make the test strips. In order to immediately identify the place and purpose of this machine in the lab, the company states that the Densometer absolutely and completely eliminates the necessity of numbered test strips which are now employed, effecting at the outset a saving of the time in processing and the material of such strips and, especially, the ensuing cost incidental to errors arising from the human judg ment of density which is no small consideration as every lab man will recognize. In passing upon the ability of the human eye in this respect it is interesting to review what Mr. James L. McCoy, of the Westinghouse Lamp Co., has to say in a recent issue of the "International Photographers Bulletin." "The unassisted eye at its best is considered unstable with a possible error of 100 per cent or more from day to day when used as a light intensity measuring instrument. It is unreasonable to expect that two or more men would come very close in a simultaneous check." Corroborating the above statement of Mr. McCoy's, it has been the experience of Messrs. Whitson and Physioc in checking up on the ability of the men employed in this capacity, where a certain degree of skill should obtain, that they were unable to check back on their figures from the test strips — that is, ten or fifteen test strips were employed and numbered consecutively, and the optical readings of the operator were taken and marked down, and after a sufficient time had elapsed for the memory to fatigue a repeat check was made by the same operator with the original strips and an error as high as 50 per cent was obtained while he believed that he was exercising his soundest judgment; which is another but at present unavoidable reason for density arguments, and unsatisfactory prints. Whereas an indefinite number of runs have been made on the Densometer with the same series of scenes and a 100 per cent cheeck was obtained, and that repeated from day to day. In fact the machine is the first constructive step to be practically taken to install a reference system of light units which can be accepted as a standard by the entire picture industry the same as exists with the petroleum industry with their scientific index; the electrical industry with their universal reference units or for that matter in every industry which the reader may name for himself excepting the motion picture industry which has suffered from the lack of such a standard. In fact it is to the picture industry what the micrometer is to the machinist, without which he would have to use the "thumb rule" and is what precisely obtains today in the laboratory — the "thumb rule." And this machine is dedicated to just such a need for improved efficiency. It is needless to say that the machine is electrical in principle and has been corrected and integrated to follow a visibility curve reading directly in printer lights, from a moving needle indicator. As has been stated in the first part of this article the Densometer which is now being announced is the third working model built, which the company declare to be their production type model and which embraces important improvements which have been suggested by prior experience and represents a high degree of refinement. The machine is equipped with a footage counter which indicates