Picture-Play Magazine (Sep 1923 - Feb 1924)

70 It's What You Don't See The man turns the crank. A picture is thrown on the screen. When the crank is turned still farther, a shutter blade comes between the him and the light and cuts off all illumination from the screen ; the screen is dark. Then, turning the handle still farther, the picture which is behind the lens moves away and another one. the next one on the strip of him, takes its place behind the lens. 'Still turning the crank, the shutter blade which has shut the light from the screen during the change, moves off, and the new picture behind the lens is thrown on the screen. This is the action which is kept up, very rapidly, of course, until the whole photo play is enacted. In a six-reel play, ninety-six thousand photographs are thrown on the screen in this way. Now, if it were not that the eye is an imperfect organ, movies would be an impossibility, and you wouldn't know what to do with yourself nights. Let us go back a second to the screen and look at it again. Let us presume that the pictures are turned through the camera very slowly ; say, one photograph is shown for one second, then the screen is dark for a while, then another photograph shows for a second, et cetera. If this were done, the change from picture to blank screen to picture would be very clearly seen. But increase the speed of the changing of the pictures until sixteen different ones are thrown on the screen in one second, and it looks like something else. The eye can no longer detect the brief interval during which the screen is dark and one picture is changed for another. It seems to be one moving picture, to the eye. This is all because of what is known as the persistencv of vision. The persistency of vision has nothing to do with the man who stares at you on the street. It is something entirely different. For instance : We see a picture on the screen for a brief interval of time, possibly about one twenty-fifth of a second, more or, less. That picture having been on the screen for that length of time, the light is suddenly cut off by the shutter blade revolving. Now, the question is, how long will we see the picture on the screen? Answer: for about one fiftieth of a second longer than it actually is there. That is, if a picture is shown on the screen for a brief fraction of a second, we will see it as long as it is there plus one fifteenth of a second. The image in the eye, during that time, is fading, and the scene is dying away. It is this that makes the motion picture possible. One picture is shown on the screen, then suddenly the light is shut off. Before the image in the eye has time to fade away — before a fifteenth of a second has elapsed — another picture takes its place. This is repeated again and again, and the result is that we see only one picture which appears to move, when in reality there are hundreds of pictures flashed in a series intermingled with instants when there is no picture before us at all. Indeed, so insignificant is one of those little photographs in the long strip that any one of them could be cut out and removed entirely without any one being able to detect it. For instance, when Tommy Meighan kisses Lila Lee devotedly, somebody could clip out one photograph in the series that make up the kiss, and even Giggly Gertie wouldn't miss it. If many of these little sections were removed, though, it could of course be detected. You view the screen at a distance of from twenty to one hundred feet or more. The picture on the screen looks sharply focused and brilliant. But when you get within a few inches of it, things look different. The picture that looks so sharp from a distance is merely one big blur. The beautiful eyes of the heroine which twinkle delightfully from afar seem like two flickering black splotches on a white piece of goods. The prin ciple of the projecting machine is the same principle that the professional photographer uses when he makes an enlargement from one of your negatives. He will tell you that no matter how sharply focused your negative may be he can't enlarge it, say, twenty-five times. That is, if your negative is three inches wide, he can't make an enlargement of it about six feet — seventy-two inches — wide because it would be very blurred and indistinct, and unless viewed at a distance of about twenty feet would appear very unsatisfactory. Since the image on the screen is magnified two hundred and forty times in the average movie house you can well imagine the great amount of blurring that takes place when you are close to the screen. These figures are for the average theater. In the huge Capitol Theater, in New York, the projection room adjoins the Fifty-first Street side of the building, while the screen almost touches the Fiftieth Street side of the building, the actual distance that the picture is projected being a hundred and ninety-seven feet. On the Capitol's screen the film is magnified 68,742 times ! Since absolute perfection of performance is demanded by the management of this palatial picture house the projection room has been equipped with every possible device to make this possible. Four machines are kept in service, the lenses for which cost four hundred dollars each. The electric current used by them daily approximates two hundred thousand watts, enough to illuminate an average-sized town. In the course of a day's operation, nine and one half miles of film are unwound, every inch of which is perfectly synchronized with the music score by means of synchronizing speed indicators which connect the booth with the desk of the conductor of the orchestra. The film strip is not the strongest thing in the world, and many times the ribbon breaks. At once the screen is dark and the audience begins to get impatient. They want to see the villain get that smash in the eye. If the audience gets too impatient it may begin to applaud wildly and stamp its feet, and that mustn't happen. So the projection man quickly trims the ends of the broken film — often removing a small section entirely as spoken of before — scrapes the picture off the edges of the trimmed ends, applies film adhesive, places the two ends together correctly, replaces the film in the machine and — grinds on. It takes only a very few seconds. That isn't all. Right in the most important part of the picture, the film sections might not register correctly. You've seen it too often. The hero's head is cut off at his eyebrows, and lo and behold, there's the rest of his cranium below a black line under his feet. Or his feet may be amputated and found stepping on his head. It's all because somebody somewhere, at some place, didn't mend a break rightly. And if the projector man doesn't want the manager to jump on his neck he's got to peek at the picture on the screen through a small hole six inches by twelve for hours at a time to see if everything is all right, and if not, to adjust it. In the picture palaces where perfection is demanded such a thing as a break in the film, or getting the picture out of adjustment, practically never occurs. Film almost never breaks while being projected until it gets old, and these big theaters always get the fresh, new prints. But at the Capitol Theater, the last word in precaution is obtained by having an employee go over every inch of film used in the program every morning, by hand, watching closely for the slightest flaw or indication of weakness which might possibly cause a break. And if he finds any such slight defect he mends or strengthens the film at that point. [Continued on page 95]