MOVING PICTURES HOW THEY ARE MADE AND WORKED

CONQUESTS OF SCIENCE Uniform with this Volume.

BY FREDERICK A. TALBOT

THE OIL CONQUEST OF THE WORLD LIGHTSHIPS AND LIGHTHOUSES THE RAILWAY CONQUEST OF THE WORLD STEAMSHIP CONQUEST OF THE WORLD

Philadelphia: J. B. LIPPINCOTT COMPANY London: WILLIAM HEINEMANN

Frontispiece.

TRICK CINEMATOGRAPHY—THE AUTOMOBILE ACCIDENT.

The producer giving instructions to the principal actor and his double, the legless cripple. The dummy legs in the foreground.—See page 211.

CONQUESTS OF SCIENCE

MOVING PICTURES HOW THEY ARE MADE AND WORKED

BY FREDERICK A. TALBOT

NEW EDITION

ILLUSTRATED

Philadelphia: J. B. LIPPINCOTT COMPANY London: WILLIAM HEINEMANN 1914

First Printed, January, 1912 Revised Edition, December, 1912 New Edition, November, 1914

Printed in England.

vii

PREFACE

The marvellous, universal popularity of moving pictures is my reason for writing this volume. A vast industry has been established of which the great majority of picture-palace patrons have no idea, and the moment appears timely to describe the many branches of the art.

I have endeavoured to deal with the whole subject in a popular and comprehensive manner. I have been assisted by several friends, who have enabled me to throw considerable light upon the early history of motion photography and the many problems that had to be mastered before it met with public appreciation:—MM. Weiss and Bull, the Director and Assistant-Director respectively of the Marey Institute in Paris; M. Georges Demeny; Messrs. Frank L. Dyer, the President of Thomas A. Edison, Incorporated; W. F. Greene, Robert W. Paul, James Williamson, Lumière & Sons, Richard G. Hollaman, the Eastman Kodak Company, Dr. J. Comandon, F. Percy Smith, Albert Smith, and the numerous firms engaged in one or other of the various branches of the industry.

I am indebted especially to the editor of L’Illustration, the well-known Parisian illustrated weekly newspaper, in conjunction with the Société des Établissements Gaumont, for permission to publish the photographs illustrating Chapters XIX., XX., and XXI., as well as the frontispiece;viii also to Mr. A. A. Hopkins, the author of “Magic,” and to Messrs. Munn & Co., the proprietors of The Scientific American, of New York, U.S.A.

The book makes no claim to being a practical manual, because thereby intricate technicalities would have been unavoidable. The information respecting the various mechanical aspects of cinematography are set forth in a readable manner, so that the broad principles may be understood.

While the most popular features of motion photography are described fully, I have not omitted to introduce the reader to the educational and scientific developments, which are more wonderful and fascinating. Indeed, the cinematograph will probably achieve greater triumphs in these fields than it has accomplished already as a source of amusement.

FREDERICK A. TALBOT.

ix

LIST OF ILLUSTRATIONS

1

CHAPTER I WHAT IS ANIMATED PHOTOGRAPHY?

From the day when it was found possible (by the aid of sunlight) to fix a permanent image of an object upon a sensitised surface, inventors steadily applied their ingenuity to the problem of instantaneous photography. In other words, they strove to realise the possibility of photographing an object in motion.

In our days the idea of “snap-shot” photography is such a commonplace that we can no longer realise the proportions of the task which confronted the early inventors. Probably most of us are unacquainted with the conditions under which the first photographs were taken. The writer has often heard a member of his family relate the amusing story of an ordeal which, as a lad, the latter underwent at the hands of the Frenchman, Daguerre. He was seized upon by the inventor as an experimental subject and was forced to sit in the brilliant sunlight for a long time. It seems incredible, but it is true, that when photography was in its infancy, an exposure of six hours was required to secure a recognisable impression of an object—a circumstance which left practically nothing but still life as feasible subjects for photography.

The problem which confronted the pioneers of instantaneous photography was the reduction of the period of exposure from about 20,000 seconds to a mere fraction of a second. Considering the magnitude of this difficulty, it is not surprising that the average person was sceptical as to its solution. The possibility of fixing a horse in the act of jumping, a bird in the act of flying, or an2 orator’s lips at the moment of uttering a word, must have seemed nearly as remote as the discovery of the Philosopher’s Stone. It is interesting to imagine the sensations of the sceptic of one hundred years ago, to whom instantaneous photography appeared a chimerical idea, should he be recalled to life to-day and be shown first a procession passing down the street, and a few hours afterward the same procession repeating itself before his eyes upon a screen in a darkened room, with all the semblance of reality in colour and animation.

In the end, it was the chemist who solved the problem of instantaneous photography, without which animated photography as we know it to-day would never have been even conceivable. He carried out innumerable laboratory experiments for the purpose of rendering the sensitised surface more and more susceptible to light—accelerating its actinic speed, as it is called—until at last he revolutionised photography, as he has changed nearly every other field of our modern industrial life. He succeeded in preparing a surface, or emulsion, so sensitive to light that it can take a picture clear, distinct, and full of detail, not merely in the space of one second, but in less than a thousandth part of a second—a picture equal, if not superior, to those which in the early days of photography required an exposure 20,000,000 times as long!

The wonderful achievement of instantaneous photography assumed at first a scientific rather than a commercial value. Many a “snap-shot” is taken which does not betray whether the plate has been exposed for six hours or only one-thousandth of a second; but, on the other hand, a “snap-shot” of a quickly moving subject may seize upon and fix an interesting or characteristic motion. It was this fact which led certain ingenious minds to perceive in instantaneous photography a valuable means of analysing motion. If a single photograph reproduced the exact posture of a moving subject at any given instant of time, they argued that a series of such photographs, if taken in sufficiently rapid succession, would form a complete record of the whole cycle of movements involved,3 for instance, in the jump of a horse or the flap of a bird’s wing.

Here, again, the inventor encountered a difficulty almost as great as the initial one of instantaneous photography. Not only had the chemist to devise a new sort of sensitised plate with a gelatine coating better and more convenient to handle than the medium before employed, but the mechanical engineer, the optical instrument maker, and the lens maker had to co-operate on a special sort of camera which should minimise the interval between successive exposures.

As earlier inventors had reduced the duration of the period of exposure, modern ones have succeeded in their turn in reducing the interval between exposures to a minute fraction of a second. When this result was achieved animated photography became a reality.

It was possible to secure a long series of consecutive snap-shots, or instantaneous pictures depicting motion, recorded at such brief intervals that when they were passed swiftly before the eyes they produced the illusion of movement.

At this point it is best to consider the physiological basis upon which animated photography rests. The word illusion, as used above, correctly describes what takes place. The eye sees a swift succession of instantaneous photographs; but it is deluded into believing that it sees actual movement.

We have all marvelled at the magician who causes bottles, eggs, birds, and animals to appear and disappear mysteriously before our very eyes. We know that it is trickery, pure and simple: that the eye is being deceived. The camera is a far more perfect trickster than the most accomplished illusionist that has ever lived, and moving pictures are the most cunning illusion that has ever been devised.

In order to convey this delusion, the photographer has taken advantage of one deficiency of the human eye. This wonderful organ of ours has a defect which is known as “visual persistence.” Briefly defined, this means that4 the brain persists in seeing an object after it is no longer visible to the eye. I will make this clear by further explanation.

The eye is in itself a wonderful camera. The imprint of an object is received upon a nervous membrane which is called the retina. This is connected with the brain, where the actual conception of the impression is formed, by the optic nerve. The picture therefore is photographed in the eye and transmitted from that point to the brain. Now a certain period of time must elapse in the conveyance of this picture from the retina along the optic nerve to the brain, in the same manner that an electric current flowing through a wire, or water passing through a pipe, must take a certain amount of time to travel from one point to another, although the movement may be so rapid that the time occupied on the journey is reduced to an infinitesimal point and might be considered instantaneous. When the picture reaches the brain a further length of time is required to bring about its construction, for the brain is something like the photographic plate, and the picture requires developing. In this respect the brain is somewhat sluggish, for when it has formulated the picture imprinted

on the eye, it will retain that picture even after the reality has disappeared from sight.

This peculiarity can be tested very easily. Suppose the eye is focussed upon a white screen. A picture suddenly appears. The image is reflected upon the retina of the eye, and transmitted thence to the brain along the optic nerve. Before the impression reaches the brain the picture has vanished from the sight of the eye. Yet the image still lingers in the brain; the latter persists in seeing what is no longer apparent to the eye, just as plainly and as distinctly as if it were in full view. When the image does disappear, it fades away gradually from the brain.

True, the duration of this continued impression in the brain is very brief. In the average person it approximates about 2/48ths of a second, which appears so short as not to be worth consideration. Still, in a fraction of time a good deal may happen, and in the case of animated5 photography it suffices to bring a second picture before the eye ere the impression of the preceding image has faded from the brain. The result is that the second picture becomes superimposed in the brain upon the preceding image; and being stronger and more brilliant, it causes the disappearing impression to merge or dissolve into itself.

Indeed, one might go farther, and say that the brain acts in the same manner as a dissolving lantern. This apparatus is very familiar to us all, and in its most approved type one view is dissolved into another. For the purpose two lanterns are required, placed either side by side or one above the other, and both focussed upon the screen. For the purpose of illustrating our complex point we will consider that they are one above the other. A slide is projected brilliantly from the uppermost lantern. Presently the moment arrives to change the slide. If the operator withdrew it from the upper lantern and inserted another there would be a defined break or blank interval upon the screen betraying the change. So he inserts the new slide in the lower lantern, at the same time increasing the volume of light emitted from that lantern, and diminishing the volume thrown from the upper lantern. The result is that the picture projected from the upper lantern becomes fainter and fainter, while that shown by the lower lantern becomes stronger and stronger, until

only the latter is seen upon the screen—the former has merged or dissolved into the latter.

The same action takes place in the brain in connection with cinematography. A picture is thrown upon the screen, and remains visible for 1/32nd part of a second. It is then eclipsed by the shutter, and—supposing that the photographs are taken at the rate of sixteen pictures per second—for the next 1/32nd part of a second the screen is darkened owing to the passage of the shutter. This division of time is not strictly correct, as we shall see later, but for present purposes I have considered the intervals of exposure and eclipse to be of equal duration.

Now as a picture will linger in the brain for 2/48ths of6 a second after it has vanished from the sight of the eye, the brain retains the impression during 1/32nd part of a second, while the shutter is passing across the lens. The second picture now comes before the eye, and although the previous picture still will remain in the brain for another 1/96th part of a second—the difference between 1/32nd and 2/48ths—the new picture, being the more brilliant, becomes superimposed upon that already obtained, and consequently causes the former dying image to merge into the later and brighter impression. This successive dissolution of one picture into the other continues until the whole string of snap-shots is exhausted. It will be noticed that every picture remains on the screen for 1/32nd of a second, followed by a period of darkness of nearly equal duration, the pictures thus being projected at the rate of sixteen per second.

The illusion of movement is enhanced by the fact that all fixed and stationary objects retain their relative positions in each succeeding image. Suppose, for instance, that a series of pictures, depicting a man walking along a street, are being shown upon a screen. In the first picture the man is shown with his left foot in the air. This remains in sight for 1/32nd of a second, and then disappears suddenly. Though the picture has vanished from the eye, the brain still persists in seeing the left foot slightly raised. One thirty-second part of a second later the next picture shows the man with his left foot on the ground. The shops, houses, and other stationary objects in the second image occupy the positions shown in the first picture, and consequently the dying impression of these objects is revived, while the brain receives the impression that the man has changed the position of his foot in relation to the stationary objects, and the left foot which was raised melts into the left foot upon the ground. The eye imagines that it sees the left foot descend. Another 1/32nd part

of a second passes, and the right foot is seen elevated, but the fixed objects retain their positions still, and so on. The brain only notices the difference in the position of the moving objects, and thus secures an illusory idea that7 movement is taking place. I have taken a very simple example to illustrate the idea. As a matter of fact, moving pictures of men walking are seldom perfectly successful, generally having a jerky movement.

Thus we have seen what we describe as animated photography is not animation at all. All that happens is that a long string of snap-shot photographs, taken at intervals of 1/24th or 1/32nd part of a second, are passed at rapid speed before the eye. If the pictures are projected at the rate of one per second they resemble ordinary magic lantern projections. As the operator slowly and gradually increases the speed, the figures shown in the pictures assume a spasmodic motion, as if their limbs were moved jerkily by means of strings; this action becoming less and less pronounced as the speed is accelerated, until, at last, when the operator gains the requisite rate of projection, the jerky movement becomes resolved into steady rhythmic action.

In the early days it was difficult to convey the impression that motion was being shown, because the movement of the shutter cutting off the picture was so emphasised as to convey a distinct sense of blankness between the successive images. This regular intermittent occurrence of invisibility, described as “flicker,” caused tremendous strain to the eyes, and provoked nauseating headache. When the flicker was eliminated the strain ceased; the illusion was rendered more perfect as well.

In order to satisfy one’s self that the semblance of animation is an illusion, one has only to compare the projection of a moving object upon the screen, and its appearance in the camera obscura. In the latter case absolute continuous motion is shown. It may be said that complete animation by photography is quite out of the question with the single camera and projector. How it can be avoided and a more perfect camera obscura effect produced upon the screen is described later. Mechanical ingenuity has not succeeded yet in achieving such a result by means of a single lens.

As a matter of fact, only one-half or less of the movement8 that actually takes place is recorded upon the film. What is lost occurs during the period the shutter is closed after exposure, in order to permit a fresh area of sensitised surface to be brought into position behind the lens. However, the lapses are equal in point of time; and when sixteen pictures are taken per second, the interruption in the movement is not detected by the brain.

It may be asked why the operator confines himself to photographing at a speed of about sixteen pictures per second. This question is governed for the most part by economical motives. Film is expensive, and therefore the obvious point is to consume the minimum of material to secure the illusion. When Edison produced the kinetoscope, at least thirty pictures per second were necessary to bring about the illusion, but Messrs. Lumière and Paul, by means of their apparatuses, which were the first commercial cinematographs, reduced the number to sixteen pictures per second. If twenty-four photographs were taken and projected per second the result would be practically no better than when only sixteen pictures were made in the same period, so that the additional eight pictures and their requisite length of film represent so much wasted effort and material.

This law in regard to visual persistence concerning the number of pictures per second holds good only so long as pictures are taken and projected in monochrome or black and white. When animation in colour is introduced, the illusory effect produced upon the brain becomes disturbed, as is explained in the chapter dealing with this latter development of the art.

An interesting illustration of the fact that the eye is deceived may be narrated. A film of a train passing through a tunnel was required. Two trains were secured for the purpose, and at the rear of the leading train the camera was mounted in order to photograph the one following, care being observed to keep them an equal distance apart. In the darkness of the tunnel the question of illumination for the purposes of the exposures was somewhat perplexing. Various expedients were attempted, but9 all to no avail, and it appeared as if the task would have to be abandoned.