The educational screen (c1922-c1956])

April, 194} Page 127 Throughout the progress of the undertaking, the writer emphasized to teachers the relative unimportance of technical perfection, where this could be achieved only at the sacrifice of originality. It is easy to copy a textbook illustration photographically, but the edu- cational values described above are thereby largely short-circuited. Moreover, the original drawings of children have a vitality seldom found in textbook pic- tures. The accompanying illustration is reproduced from a color slide of which the original was about eighteen by twenty-seven inches in size, done in lovely pastel colors by a fourth grade child. The title of this particular unit was "Old China"; other classes did units on Benjamin Franklin, Andrew Jackson, The Pilgrims, Brazilian Rubber, Health Habits, etc. Although it would be an exaggeration to assert that any snapshot taker can produce successful Kodachrome slides, it is nevertheless true that one need not be a professional photographer to achieve perfectly satis- factory results. Anyone who can produce acceptable photographs under artificial light, can undoubtedly do at least as well with Kodachrome. The fact that pro- cessing is included in the cost of the film removes at least the variable of developing and printing. The minimum equipment required includes a suitable 35 millimeter camera, tripod, copying easel, lights, and lens extension tubes. As in most photography, the quality and cost of the equipment may vary consider- ably, with an accompanying variation in results which is not, however, directly proportional to the difference in cost. For example, although it cannot be denied that a Cf)ntax camera costing $250.00 will produce better results than an Argus costing $35.00, the difference is slight enough to be apparent to only the most critical observer. Moreover, many excellent features of the Contax camera which serve to raise its price are of no particular value for our immediate purpose, however desirable they nmy be for general or otherwise special- ized photography. Thus, while the writer's Contax has an ultra-rapid f-1.5 lens, no picture in the project was taken at a lens opening greater than f-4.5, which falls well within the range of even the Argus camera. The chief requirement of the camera is one that is not met by all makes, and is in fact lacking on several that are far from inexpensive. That is. the lens must be demountable so that an extension ring or tube may be inserted in order to achieve proper focus at distances as clo.se as ten inches. This is particularly necessary in photographing typewritten sub-titles, and other small subjects. As the project will probably involve a considerable amount of "copying," i. e., photographing paintings, drawings, maps, and other plane surfaces, it is essential to i)urchase or con.struct a suitable copying easel, which greatly reduces the time and trouble involved. The illustration shows a very .satisfactory home-made affair, which has served admirably. It consists of an upright wot)den surface, about fourteen by twenty-one inches in size, fixed at right angles to a small sliding platform wiiich carries the camera, mounted by its tripod screw. .-\fter the camera has been mounted, it is slid up close to the easel surface, so that the lens may be accurately centered upon the easel, after which tlie easel is marked A child's colored drawing which was reproduced on a Kodachrome slide for a unit on China. off in numbered rectangles, at half-inch intervals, each rectangle retaining the proportions of two to three, as the picture size is twenty-four by thirty-.six millimeters. These rectangles are indispensable for rapid and accu- rate work, patricularly if the camera chosen has a re- movable back, which permits ground-glass focusing. If the latter is the case, the camera is mounted on its platform, and accurate focus achieved on the ground- glass for each rectangle in succession. .A.t such close distances, it will be necessary to u.se the extension rings or tube mentioned above, and perhaps also one or more supplementary slip-on lenses of the Proxar type. Ameri- can-made supplementary lenses are perfectly satisfac- tory, and cost only about two dollars apiece. As each correct focus is achieved, the proper setting of the sliding platform is marked by a permanent line on the "track." numbered to correspond with the respective rectangle. The lens .setting is also marked at this line. Thus, once the easel has been marked for every rectangle, all that is necessary to photograph a given drawing is to center the drawing on the easel, note which rectangle most closely approximates the drawing in size, and proceed to focus the camera according to the rectangle selected. Some such procedure is abso- lutely necessary to insure accurate framing and focus. as the "finder" of any camera is inoperative at dis- tances closer than three feet, and inaccurate even at three feet. The illustration also shows the lights and reflectors used with the easel. (One reflector has been removed to avoid blocking the easel.) The Hghts need not be stronger than sixty watts, as long exposures may easily be given. The essential precaution to be ob.served is that each light should be at an angle of at least forty-five degrees to the picture, in order to avoid undesirable reflections. {Concluded on pane 146)