Movie Makers (Jan-Dec 1950)

145 BE GIVEN ADDED EXPOSURE? I AM glad to receive Mr. Moore's recent letter and to have the chance of commenting on the discussion of Gilbert B. Jansen, jr.. ACL. on the characteristics of outdated film. The use of outdated motion picture film is probably of less importance today than it was four or five years ago, since by now nearly all of the Army surplus film — the chief source of such materials — has been used up. There are, however, occasions when someone will run across a roll or two of film that was mislaid. Such persons write to us to find out if such films can still be used. We, of course, advise that the use of such film is a gamble and that they should not use it for pictures of important subjects which cannot be rephotographed in the event of unsatisfactory results. As for the details, the whole subject of film storage before exposure is quite a lengthy one and one on which I would not undertake to give general advice in the short space provided by a discussion of this type. I might say, however, that I have seen pictures made on Kodachrome film that had passed its expiration date by five years and which appeared for all practical purposes as though it was fresh film. On the other hand, I have seen pictures made on fresh film that had been improperly stored wherein the film had apparently been ruined in less than a month's time. "Keeping-fog a factor" To comment specifically on some of the paragraphs in Mr. Jansen's letter . . . In regard to paragraph 4, there is no evidence to indicate what Mr. Jansen considers to be a "normal" exposure. There are some movie makers who expose everything ^ to 1 stop more than I would consider the correct exposure and they seem to be quite satisfied with results that are a little on the light side. On the other hand, there are other movie makers who have a tendency to expose % to 1 stop less than what I consider normal exposure. If Mr. Jansen happens to be one that shoots on the full side, then it is quite possible that he could make pictures on film that was really a stop slower than fresh film and still get results that would be acceptable for density. At the same time he would feel that he had given the same exposure that he normally would. (Upon inquiry on this point, Mr. Jansen reports that the "normal" exposure he used was f/4.5 at 16 frames per second. According to the Movie Kodaguide, correct exposure for outdoor Kodachrome in open shade is f/2.8, so that, if anything, Mr. Jansen was underexposing the outdated film in question. — Ed. ) In regard to the 5th paragraph, Mr. Jansen is quite correct. Age, or keeping, fog is an important factor, and "Make test exposures" THANK you very much for giving us the opportunity to review Mr. Jansen's letter on the subject of exposing outdated film. His comments on the subject fall right in line with our observations of old emulsions. It has been our experience that out of date Ansco Color film usually has a tendency towards poor color balance but not necessarily of any one specific type, although bluish results seem to predominate. As you know, the expiration date stamped on each carton of Ansco Color film represents the normal life expectancy of the material when it is subjected to average storage conditions. When carefully stored, under conditions which are nearly ideal, there is greater probability that the material will deteriorate less rapidly and that the film will remain in good condition for some time beyond the expiration date. Deterioration of film, of course, is greatly accelerated by high temperatures and high humidities. Other conditions, such as mechanical pressure EDWARD F. BREWER, Ansco and exposures to certain vapors and gases, can appreciably shorten the useful life of the film. For optimum storage, we recommend that films be stored in a cool, dry place (i.e., a temperature of approximately 60° F. and relative humidity in the neighborhood of 30 to 40 percent). Normal variations from these ideal conditions which occur with changes in the weather are not of sufficient importance in most cases to cause any noticeable effects. We fully agree with Mr. Jansen that the use of outdated film is, at best, a gamble and for consistently good results we recommend that fresh film be used. In any event, we would always suggest that photographers using outdated film make test exposures prior to doing any important work so they will know beforehand whether the results from the material in question will be acceptable. Thank you again for your interest in writing to us regarding Mr. Jansen's interesting letter. HARRIS B. TUTTLE, ACL Eastman Kodak Company keeping fog is quite evident in the samples enclosed with your letter. Keeping fog usually fogs the silver in the top or blue-sensitive layer of Kodachrome film. I believe this is what has occurred in this case because the pictures are excessively blue and lacking in yellow pigment. There is, of course, some effect of keeping fog in all three layers. It is important to note that whatever causes the fogging usually affects the larger and more sensitive grains first, leaving only the medium and smaller sized grains unaffected to form whatever image is created when the film is exposed. It is precisely because the larger grains are already exposed by fog that it is necessary to give more exposure to the film. Because, after these larger grains have been destroyed by fog, the film behaves like a smaller-grained or slower type of emulsion. In regard to his 6th paragraph, I believe it is generally recognized that all types of color film appear to be more susceptible to changes after the expiration date than black and white materials. It is probably also safe to say that color films are in general more susceptible to high temperature and high relative humidity than black and white materials. This is due partly to the complex nature of the three layer type of emulsion and also to the fact that keeping fog can affect one layer to a greater degree than another. Therefore, it invariably throws the final pictures out of color balance. I don't agree with Mr. Jansen that if the film is in poor condition due to improper storage, it is always necessary to throw it away as useless. It is possible that film which is past its expiration date could be used for two or three purposes wherein accurate color rendering is not of too much importance. One way would be to use it in photographing sunsets. If the film rendered the sunset a little bluer or redder than normal, it might enhance the beauty of the sunset so that it would be more glamorous than nature intended. Second, it might be possible to use the film in photographing street scenes at night merely for the recording of neon and other advertising lighting effects. Third, it might be used for making titles wherein the degree of off-color produced in the final image would be entirely acceptable as a colored title. I am glad that you brought this to our attention and gave me an opportunity to make the above comments.