Movie Makers (Jan-Dec 1948)

402 FINE POINTS OF FILM CARE From package to projector, your films deserve the best of care. Here's what to watch for JAMES W. MOORE, ACL WE don't need to tell you how precious those family pictures are today — how infinitely more precious they will grow with the passing years! There are those heart warming scenes of Mother and Son just home from the hospital: those hilarious scenes as he staggers through his first steps; those once-in-a-lifetime sequences of the first Christmas and the first birthday — you know the magic of these movies far better than we can tell you . . . Why, then, dont you lake good care of them? Perhaps — we can then answer ourself — it is because no one as yet has explained to you the problems of film care and the really simple solutions to these problems. So here goes. PROTECTION BEFORE EXPOSURE The two chief hazards to any photographic emulsion — even before exposure — are humidity and heat. Of these two, an excess of humidity is the condition more likely to be encountered by the amateur movie maker under average domestic conditions. Fortunately, however, the packaging now used on modern color films is adequate protection against average humidity conditions. Magazine Kodachrome, for example, is supplied in heat-sealed foil packages, while the roll films are offered in taped cans. Either method (known as domestic packaging to the manufacturer) provides ample protection against normal handling and the humidities commonly encountered in temperate zones throughout the period of the film's expiration date. This regular packing is also sufficiently moisture-resistant to protect films taken on short trips to tropical regions. For longer stays in pronouncedly humid areas (especially when combined with high heat) , tropical or export packaging is indicated. This can be obtained on order from the film manufacturer. THE EFFECTS OF HUMIDITY Once any one of these film packages is opened, however, the moisture content of the film quickly reaches equilibrium with that of the air — and film enemy No. 1 may begin to act. High humidity can cause moisture spots on the film, the transference of film backing to the emulsion, and the faulty operation of cameras through sticking of the film to itself. Also, because the gelatin used in all photographic emulsions is an excellent culture medium, moisture will further the growth of fungus on the film. These are some of the possible and extreme effects of humidity once the film packaging has been broken. Although they are not likely to be set in motion under ordinary conditions of film tenure, it is well to be aware of them and to be on your guard. Obviously, your best protection against humidity is the film's unbroken packaging. THE EFFECTS OF HEAT This packing, however, cannot protect against high temperatures; and excess heat, besides accelerating the possible actions of humidity, can affect film adversely in its own right. Too long exposure to high temperatures will promote the growth of latent images, induce film fogging, cause loss of contrast and reduce film speed. This last effect is especially serious in the case of color films, since their multiple layers of emulsion may be affected at different rates, thus causing a change of color balance. Loss in film speed is unlikely to occur during the indicated life of the film. After that date, about one half a stop more exposure should be allowed for up to six months overdating, with one to one and one half stops more for a year of overage. STORAGE BEFORE EXPOSURE Under the current conditions of film supply it may seem unnecessary to outline the recommended methods of storing unexposed supplies of film. But times will change, and perhaps by next summer's heat wave you will need to know. To begin with, of course, do not break the moistureresistant packaging — thus barring normal humidity. Against excess heat, the temperature recommendations (all Fahrenheit) are as follows: storage up to two months — below 75 degrees; up to six months — below 60 degrees; up to twelve months — below 50 degrees. Wherever possible, the relative humidity should be kept between 40 and 60 percent, with the lower range the more desirable. Under average temperate zone conditions adequate protection will be afforded by avoiding steampipes and other heat sources, uninsulated top floors, automobile glove compartments and other areas exposed to the sun. In the tropics and during the summer heat of temperate zones refrigerated storage is recommended. Home refrigerators are excellent for this purpose, provided the film is tropically packed or that domestically packaged units are placed in a sealed can or jar. Ice boxes, which give off a great deal of moisture, are not suitable. And now one caution as to use of refrigerated films: to avoid condensation of moisture on the cold film layers, packages should be removed from refrigeration several hours (and preferably up to twenty four) before use. Do not break the packaging during this period. PROTECTION AFTER EXPOSURE As already suggested, your film supplies are reasonably safe for short periods of time even under tropical conditions of humidity and heat — as long as the packaging remains unbroken. It is only after the film comes out of the box that these weather conditions begin to get in their worst licks. What, then, are the practical recommendations for an amateur movie maker on a southern holiday? The following will help: (1) Keep all film supplies in as cool a place as possible and sealed until ready for immediate use. (2) Once a film [Continued on page 408]