Home Movies (Jan-Dec 1940)

. . . Published in Hollywood 1940 HOME MOVIES Reported by Advisory Editors Reed E. Snyder Russell A. Dixon and W. E. CLYMA u EXPOSURE a row L^OLl • • • ! T HREE of our advisory editors, each an amateur cinefilmer of considerable experience and selected by their respective clubs to serve on our advisory staff, give you the benefit of their many years’ experience in telling you about exposure this month. Editor Snyder writes about the fundamental idea of exposure and its relation to lens markings. Editor Dixon tells you how to use an exposure meter to solve your exposure problems, and Editor Clyma covers the use of lighting equipment indoors and its relation to Kodachrome as well as black and white films. Reed E. Snyder believes the beginning amateur movie maker should at once fully understand the fundamentals of exposure and particularly the ■ exposure markings of the camera lens. He writes : “To very quickly allay any fears the beginner may have concerning exposure, I would like to make the statement that exposures with a movie camera are much less difficult than with a still , camera, in inexperienced hands. “First of all, there are just two very important I things to fix in one’s mind so that they will never be forgotten. “1. Amount of light entering lens is not increased as the stop numbers (or diaphragm settings) are increased. In fact, the result is directly opposite. For example an f/3.5 lens, with stop wide open, will allow more light (about twice as II much) to pass through the lens than will the ! numerically larger stop setting of f/4.5, and so | on down the line to f/16. We always say stop * down to f 8, f 11 and f/16, and we must remem ber that this will always mean less light through the lens. “2. Always remember that you will have more light entering your lens when taking pictures of objects or scenes at a distance from the camera. This is because you are receiving light reflected from a great area. Then, if this is true, there will be less light enter the lens from close objects ] (close-ups) because the object reflecting the light, in this instance, is much smaller. So we learn from this that we stop down for distant shots and open the lens for close-ups. Of course, I’m speaking now of light conditions being equal. An exam ple will illustrate: Suppose we take a scene of a home with a child coming out the door, a long shot, and we use stop f/11. To get a close-up of the child’s head and shoulders at, say, 3 feet, we will probably have to open the diaphragm to f/5.6 or f/4.5 to keep our exposure correct. “And now that we have these two things firmly fixed in our minds, we will discuss briefly this thing called exposure. ‘Correct exposure’ means that our film emulsion has received exactly the right amount of light to produce a lifelike, cleancut reproduction of the object photographed. So, exposure is a function of time (shutter speed) and aperture (stop opening). In movie cameras the time of our exposures is fixed, the average being about 1/32 sec. for 16 frames per sec., which is the speed the amateur will use about 95% of the time. You see, really all we have to consider is that diaphragm setting or stop number we discussed previously. You can get a better idea of how this operates by looking into your ® Continued on page 35 • Shirley Temple's excellent knowledge of exposure is attributable to the guidance she received from ace cinematographer Arthur C. Miller, shown here schooling Shirley in the whys andwherefors of the "f" stop. 20th Century -Fox Photo