International photographer (Jan-Dec 1941)

l6MM. dEpARTMENT WHAT SHOULDN'T I DO? (II) Continuing along on the premise that it is frequently more constructive to lay down rules of what not to do than what should be done, as we started doing last month, we come to a problem that has caused more ruined pictures in itself than many other problems combined. DONT SHOOT A SCENE IN WHICH AN UNBALANCED LIGHT CONDITION PREVAILS. UNLESS SOME SORT OF CORRECTION IS INTRODUCED. Many amateurs have come to us with scenes — long shots and close-ups, both — where part of the picture would be "washed out" and part of it almost black. If not completely black. And want to know why it looked that way, and what they should have done to correct the situation, or what they shouldn't have done. To give a little clearer understanding of the mechanics of the problem, let us take the old stand-by, the human eye. When we are walking down a street where the sunlight is occasionally shaded by objects, and look at a person walking alongside as he passes from the sunlight to the shadow, we do not have the sensation of losing all the detail of his features when he is in the sunlight, and then finding him so dark that we cannot see him when he is in the shadow. Instead, the iris of the eye, acting as the diaphragm of a lens on a camera, closes down and lets less light into the eye when he is in the sunlight, and then opens up and permits more light to enter when he is in the shadow. When the eye perceives a large area that is partially in the bright sunlight and partially in the shade, then the iris will "compromise" and permit more light to enter than is necessary for the bright objects and give the shadows a chance to register, even though there still isn't enough light admitted from the shadows to permit really good vision. The result is that the brightly lighted objects will appear brighter to the eye, and those in the shade darker than they would if they were viewed individually. If the shade predominates the iris will give it preference, and we'll be able to see objects here more easily; but if sunlight predominates, [hen it will actually be difficult to see things in the shade, hecause of the fact that large amounts of light will cause the iris to react and close down. It is possible to do the same thing with a camera, except that we are a little more limited. In the eye, when we look directly towards ,i certain objecl or scene the construe! ion of the retina of the eye will overcome the effcels of very great inequalities by virtue of the fact that a large part of the retina is covered by a coating that retards clear vision, lliis coating being absent in the center of the retina directly behind the eyeball, permitting perfectly clear vision here and the ability for the eye to 20 concentrate on an object. The camera differs in this respect in that it records the entire scene as the eye would see it without the protective covering. This is the first contributing factor to the "unnaturalness" of the unbalanced picture. The next, and perhaps even more important factor, is the mechanical limitations of the physio-chemical characteristics of an emulsion. When a film has been given a normal amount of development there is a "normal" range of exposures for that film that will result in "normal" densities. In other words, if there are objects in the scene that will reflect varying amounts of light to the camera, causing varying amounts of exposure on different parts of the film, if the light these objects reflect is of the amount to cause a "normal" exposure on the film, then these variations will produce proportionate variations in the densities produced in the emulsion. When the exposures fall below or go above this normal range the emulsion reacts abnormally. The variations in light and shade produced by the objects in the scene will not produce proportionate variations in light and shade on the film, this being due to the physio-chemical characteristics all films possess. In addition to this we have another factor contributing to the failure of a scene photographed without consideration for a balanced light condition. Let's assume that we have met the requirements to a degree by staying within the limits of a "normal" range of exposures, but that we go to the extremes of these limits. Such a condition could obtain where the extreme highlights and extreme shadows were not sufficiently great in nature to bring about a disproportionate response in density on the developed film. We would then be faced with the difficulty of printing such a scene because a printing light sufficiently strong to penetrate the heavy silver deposit of the negative and give a normal exposure to the positive would be too strong for the shadows, and would make them too dark, even though they would be of correct contrast because of the proportionate variation response. A light low enough in value to give the correct printing exposure to the shadows would be too weak to penetrate the highlights to give them a normal exposure on the print. Fortunately, however, this latter difficulty does not concern reversal film for obvious reasons. But their effects are not entirely absent because the range of "normal" exposures is so much smaller on reversal film than that of a negative film. There are several ways to deal with a situation of this sort. In all of them a "compromise" must be effected in exposing the two extremes, the same as the eye does. The easiest and most logical one is to pick an angle that will minimize the inequality of the light condition. Assuming that we are shooting in sunlight — where we are most apt to encounter a condition of this nature — we will find that if the sun is directly behind us the shadows will fall behind the objects we are photographing, and the camera will see little of them. This, however, will tend to make the scene look flat due to the absence of shadows. At the other extreme, shooting the scene with the sun coming towards us, we will have a picture where the shadows will occupy as prominent a place as the objects themselves. By compromising, and picking an angle where these shadows are there, but by virtue of the camera position are not of such magnitude or prominence as to constitute a major part of the scene, dealing with them then is no problem. There are times, however, when this is impossible, or when action is taking place in both the shadows and in the sunlit areas, and we want to photograph them both. Here the compromise becomes most important, and that area in which the most important action is taking place is favored most. If the sky has a light haze it will act as a reflector, and will "fill in" the shadows sufficiently to give a good light balance — if enough open sky, or open water, is present. Sand on beaches is an excellent reflector, as are white or light colored buildings. If the sky is a deep blue, a blue filter will help, by holding back the large amounts of red and yellows present in the sunlight and giving the blue of the sky a chance to build up in the shadows. Neutral density filters are of help where a glare exists. Much better, though, is the use of some means of throwing light into the dark areas artificially, using either reflectors made for the purpose, or lights. This means is useful only where relatively small areas are being photographed. It is usually in these small areas where the natural reflections of haze, clouds, sand, or water cannot be used to practical advantage. And the large ones cannot be artificially illuminated in a practical manner by an amateur because of the large equipment requirements. When none of these corrections can be introduced for one reason or another, and the scene has great extremes in values of light distribution, there is only one thing to do to prevent a photographic failure. And that is not to shoot it. We have laid down a photographic rule. That does not mean that under no circumstances should an unbalanced light condition ever be photographed. When one reaches that state of proficiency where he can determine beforehand what the exact result on the screen will be and can deal with the situation accordingly to achieve a technically perfect negative, a situation with an unbalanced light condition that would result in a photographic failure for an average person can be turned into a scene that will heighten the dramatic effect desired to create. It is one of the rules that must be broken by experts.