The Photoplay: A Psychological Study

by Hugo Münsterberg

Our esthetic interest turns to the means by which the photoplay influences the mind of the spectator. If we try to understand and to explain the means by which music exerts its powerful effects, we do not reach our goal by describing the structure of the piano and of the violin, or by explaining the physical laws of sound. We must proceed to the psychology and ask for the mental processes of the hearing of tones and of chords, of harmonies and disharmonies, of tone qualities and tone intensities, of rhythms and phrases, and must trace how these elements are combined in the melodies and compositions. In this way we turn to the photoplay, at first with a purely psychological interest, and ask for the elementary excitements of the mind which enter into our experience of the moving pictures. We now disregard entirely the idea of the theater performance. We should block our way if we were to start from the theater and were to ask how much is left out in the mere photographic substitute. We approach the art of the film theater as if it stood entirely on its own ground, and extinguish all memory of the world of actors. We analyze the mental processes which this specific form of artistic endeavor produces in us.

To begin at the beginning, the photoplay consists of a series of flat pictures in contrast to the plastic objects of the real world which surrounds us. But we may stop at once: what does it mean to say that the surroundings appear to the mind plastic and the moving pictures flat? The psychology of this difference is easily misunderstood. Of course, when we are sitting in the picture palace we know that we see a flat screen and that the object which we see has only two dimensions, right-left, and up-down, but not the third dimension of depth, of distance toward us or away from us. It is flat like a picture and never plastic like a work of sculpture or architecture or like a stage. Yet this is knowledge and not immediate impression. We have no right whatever to say that the scenes which we see on the screen appear to us as flat pictures.

We may become more strongly conscious of this difference between an object of our knowledge and an object of our impression, if we remember a well-known instrument, the stereoscope. The stereoscope, which was quite familiar to the parlor of a former generation, consists of two prisms through which the two eyes look toward two photographic views of a landscape. But the two photographic views are not identical. The landscape is taken from two different points of view, once from the right and once from the left. As soon as these two views are put into the stereoscope the right eye sees through the prism only the view from the right, the left eye only the view from the left. We know very well that only two flat pictures are before us; yet we cannot help seeing the landscape in strongly plastic forms. The two different views are combined in one presentation of the landscape in which the distant objects appear much further away from us than the foreground. We feel immediately the depth of things. It is as if we were looking at a small plastic model of the landscape and in spite of our objective knowledge cannot recognize the flat pictures in the solid forms which we perceive. It cannot be otherwise, because whenever in practical life we see an object, a vase on our table, as a solid body, we get the impression of its plastic character first of all by seeing it with our two eyes from two different points of view. The perspective in which our right eye sees the things on our table is different from the perspective for the left eye. Our plastic seeing therefore depends upon this combination of two different perspective views, and whenever we offer to the two eyes two such one-sided views, they must be combined into the impression of the substantial thing. The stereoscope thus illustrates clearly that the knowledge of the flat character of pictures by no means excludes the actual perception of depth, and the question arises whether the moving pictures of the photoplay, in spite of our knowledge concerning the flatness of the screen, do not give us after all the impression of actual depth.

It may be said offhand that even the complete appearance of depth such as the stereoscope offers would be in no way contradictory to the idea of moving pictures. Then the photoplay would give the same plastic impression which the real stage offers. All that would be needed is this. When the actors play the scenes, not a single but a double camera would have to take the pictures. Such a double camera focuses the scene from two different points of view, corresponding to the position of the two eyes. Both films are then to be projected on the screen at the same time by a double projection apparatus which secures complete correspondence of the two pictures so that in every instance the left and the right view are overlapping on the screen. This would give, of course, a chaotic, blurring image. But if the apparatus which projects the left side view has a green glass in front of the lens and the one which projects the right side view a red glass, and every person in the audience has a pair of spectacles with the left glass green and the right glass red—a cardboard lorgnette with red and green gelatine paper would do the same service and costs only a few cents—the left eye would see only the left view, the right eye only the right view. We could not see the red lines through the green glass nor the green lines through the red glass. In the moment the left eye gets the left side view only and the right eye the right side view, the whole chaos of lines on the screen is organized and we see the pictured room on the screen with the same depth as if it were really a solid room set on the stage and as if the rear wall in the room were actually ten or twenty feet behind the furniture in the front. The effect is so striking that no one can overcome the feeling of depth under these conditions.

But while the regular motion pictures certainly do not offer us this complete plastic impression, it would simply be the usual confusion between knowledge about the picture and its real appearance if we were to deny that we get a certain impression of depth. If several persons move in a room, we gain distinctly the feeling that one moves behind another in the film picture. They move toward us and from us just as much as they move to the right and left. We actually perceive the chairs or the rear wall of the room as further away from us than the persons in the foreground. This is not surprising if we stop to think how we perceive the depth, for instance, of a real stage. Let us fancy that we sit in the orchestra of a real theater and see before us the stage set as a room with furniture and persons in it. We now see the different objects on the stage at different distances, some near, some far. One of the causes was just mentioned. We see everything with our right or our left eye from different points of view. But if now we close one eye and look at the stage with the right eye only, the plastic effect does not disappear. The psychological causes for this perception of depth with one eye are essentially the differences of apparent size, the perspective relations, the shadows, and the actions performed in the space. Now all these factors which help us to grasp the furniture on the stage as solid and substantial play their rôle no less in the room which is projected on the screen.

We are too readily inclined to imagine that our eye can directly grasp the different distances in our surroundings. Yet we need only imagine that a large glass plate is put in the place of the curtain covering the whole stage. Now we see the stage through the glass; and if we look at it with one eye only it is evident that every single spot on the stage must throw its light to our eye by light rays which cross the glass plate at a particular point. For our seeing it would make no difference whether the stage is actually behind that glass plate or whether all the light rays which pass through the plate come from the plate itself. If those rays with all their different shades of light and dark started from the surface of the glass plate, the effect on the one eye would necessarily be the same as if they originated at different distances behind the glass. This is exactly the case of the screen. If the pictures are well taken and the projection is sharp and we sit at the right distance from the picture, we must have the same impression as if we looked through a glass plate into a real space.

The photoplay is therefore poorly characterized if the flatness of the pictorial view is presented as an essential feature. That flatness is an objective part of the technical physical arrangements, but not a feature of that which we really see in the performance of the photoplay. We are there in the midst of a three-dimensional world, and the movements of the persons or of the animals or even of the lifeless things, like the streaming of the water in the brook or the movements of the leaves in the wind, strongly maintain our immediate impression of depth. Many secondary features characteristic of the motion picture may help. For instance, by a well-known optical illusion the feeling of depth is strengthened if the foreground is at rest and the background moving. Thus the ship passing in front of the motionless background of the harbor by no means suggests depth to the same degree as the picture taken on the gliding ship itself so that the ship appears to be at rest and the harbor itself passing by.

The depth effect is so undeniable that some minds are struck by it as the chief power in the impressions from the screen. Vachel Lindsay, the poet, feels the plastic character of the persons in the foreground so fully that he interprets those plays with much individual action as a kind of sculpture in motion. He says: "The little far off people on the oldfashioned speaking stage do not appeal to the plastic sense in this way. They are by comparison mere bits of pasteboard with sweet voices, while on the other hand the photoplay foreground is full of dumb giants. The bodies of these giants are in high sculptural relief." Others have emphasized that this strong feeling of depth touches them most when persons in the foreground stand with a far distant landscape as background—much more than when they are seen in a room. Psychologically this is not surprising either. If the scene were a real room, every detail in it would appear differently to the two eyes. In the room on the screen both eyes receive the same impression, and the result is that the consciousness of depth is inhibited. But when a far distant landscape is the only background, the impression from the picture and life is indeed the same. The trees or mountains which are several hundred feet distant from the eye give to both eyes exactly the same impression, inasmuch as the small difference of position between the two eyeballs has no influence compared with the distance of the objects from our face. We would see the mountains with both eyes alike in reality, and therefore we feel unhampered in our subjective interpretation of far distant vision when the screen offers exactly the same picture of the mountains to our two eyes. Hence in such cases we believe that we see the persons really in the foreground and the landscape far away.

Nevertheless we are never deceived; we are fully conscious of the depth, and yet we do not take it for real depth. Too much stands in the way. Some unfavorable conditions are still deficiencies of the technique; for instance, the camera picture in some respects exaggerates the distances. If we see through the open door of the rear wall into one or two other rooms, they appear like a distant corridor. Moreover we have ideal conditions for vision in the right perspective only when we sit in front of the screen at a definite distance. We ought to sit where we see the objects in the picture at the same angle at which the camera photographed the originals. If we are too near or too far or too much to one side, we perceive the plastic scene from a viewpoint which would demand an entirely different perspective than that which the camera fixated. In motionless pictures this is less disturbing; in moving pictures every new movement to or from the background must remind us of the apparent distortion. Moreover, the size and the frame and the whole setting strongly remind us of the unreality of the perceived space. But the chief point remains that we see the whole picture with both eyes and not with only one, and that we are constantly reminded of the flatness of the picture because the two eyes receive identical impressions. And we may add an argument nearly related to it, namely, that the screen as such is an object of our perception and demands an adaptation of the eye and an independent localization. We are drawn into this conflict of perception even when we look into a mirror. If we stand three feet from a large mirror on the wall, we see our reflection three feet from our eyes in the plate glass and we see it at the same time six feet from our eye behind the glass. Both localizations take hold of our mind and produce a peculiar interference. We all have learned to ignore it, but characteristic illusions remain which indicate the reality of this doubleness.

In the case of the picture on the screen this conflict is much stronger. We certainly see the depth, and yet we cannot accept it. There is too much which inhibits belief and interferes with the interpretation of the people and landscape before us as truly plastic. They are surely not simply pictures. The persons can move toward us and away from us, and the river flows into a distant valley. And yet the distance in which the people move is not the distance of our real space, such as the theater shows, and the persons themselves are not flesh and blood. It is a unique inner experience, which is characteristic of the perception of the photoplays. We have reality with all its true dimensions; and yet it keeps the fleeting, passing surface suggestion without true depth and fullness, as different from a mere picture as from a mere stage performance. It brings our mind into a peculiar complex state; and we shall see that this plays a not unimportant part in the mental make-up of the whole photoplay.