Cinematographic annual : 1930 (1930)

542 CINEMATOGRAPHIC ANNUAL ished film is projected on the screen you can quickly decide which of the three shots appears the best and, by referring to your notes, you can then compare the lens setting that produced best results with the setting recommended by the meter originally. It may be that you are in the habit of reading your meter too high or too low. This simple test will show you at once. It should be repeated under different light conditions and with a variety of different subjects. Both the film and your notes should be preserved for future reference. While all film possesses considerable latitude, a little careful testing in this way will quickly demonstate that there is a very definite lens setting that gives the best results. The old rule, "when in doubt over-expose," does not apply to film finished by the reversal process. Over-exposed film appears almost like transparent celluloid and the pictures are weak and devoid of detail. Under-exposed film, on the other hand, is dark and dense when finished. As the under-exposed film is the lesser of the two evils, the revised rules becomes, "when in doubt UNDER-EXPOSE." Incidentally, the use of a smaller lens opening will make the picture sharper and more distinct on the screen. It is, therefore, recommended that the smallest lens opening, consistent with the prevailing light conditions, be used at all times. In this discussion we are assuming that the shutter speed is constant and that the exposure is controlled exclusively changing the size of the lens opening or stop. All things being equal a long shot requires less exposure than distant objects and the use of a slightly smaller lens opening is a close up. More light enters the camera when photographing distant objects and the use of a slightly smaller lens opening is suggested. On the other hand, do not fail to open up the lens at least one stop number when shooting a close up immediately following a long shot. It is to be remembered that when shooting close ups, especially with the larger lens openings, it is essential to have the lens correctly focused. To insure accuracy the distance from the camera to the subject should be carefully measured with a tape line. Professionals always do this and you should do likewise if you want your close ups to be needle sharp on the screen. Late in the afternoon, especially in Fall and Winter, the sunlight becomes very rich in red rays. This light is very deceptive as it appears quite bright to the eye but is rather inactive photographically. Often the change in color of the light is so gradual that it passes unnoticed, but the sensitive film is not fooled and the result is the pictures are dark and under-exposed. Many methods have been devised to aid in the estimating of correct exposure. Most of these methods are rather cumbersome and complicated. While it is recognized that the many factors that enter in the determination of correct exposure make it almost impossible to devise any "rule of thumb" method to fit all cases, the following original system, worked out by the present writer and published here for the first time, will under ordinary normal conditions, give a remarkably close approximation. The simplicity of this new system makes it easy to memorize. It is based on the use of 16 mm. reversible film. Normal shutter speed and average summer light condi