The Moving Picture World (May 1907)

/ ■ l THE MOVING PICTURE WORLD. 185 The Moving Ficture Hazard dently weaker, but superposed by the image film uninjured and to be capable of using Analyzed. No. 2, and as the immovable parts coincide films a great many times. With proper exactly, our eye perceives the sensation of care a film is capable of being projected the moving object, attitude No. 1, succeed- through the machine from 500 to 800 times. A prominent underwriter who has care- e d by attitude No. 2, and so on up to atti- "Cinematography, or the art of reproduc- fully investigated the moving picture haz- tude No. 900. (The 'flickering' so detri- ing animated scenes, has not yet reached ard ra dealing with the subject says: mental to the art and injurious to the eye- the highest perfection, which would mani- "A few words as to the origin of chrono- sight of the spectators is due to the dark festly be attained in the reproduction of photography, or the photography of move- intervals which intervene between the sue- moving objects in such a manner that "they ment, may not be out of place. In the cessive pictures projected.) would appear upon the screen exactly the early part of the nineteenth century Platau T* > s necessary to have an apparatus to same in every respect as they in reality produced an instrument termed the phena- produce thus within one minute the 000 light naturally do—as they are in nature. While kistoscope, demonstrating the principles of eclipses by which 900 substitutions of sue- cinematography is far from reaching this the persistence of vision, and this subse- cessive images are obtained. These eclipses ideal, it has come to stay, and is of great quently gave rise to the zoetrope in 1845; are obtained by means of an opaque shut- value for educational and scientific pur- this optical instrument exhibited pictures **i which revolves at the rate of fifteen poses, as well as contributing to the pleas- depicting the successive attitudes of object* times in each second, and is attached so ure and amusement of a large number of in motion. In about 1870 the praxinoscope, that during its movements it intercepts the people^. s by Renault, appeared, and in 1874 the pho- light coming from the projecting lantern at ^Electroscope, knographoscope, veriscope, Vraphic revolver by Janssen. Muybridge, ^ch turn, and consequently the illumina- vitascope and cameragraph, are names ap- jchutz, Greene, Marey and other scien- tion on screen on which the image is pro- plied to various machines essentially like /» brought us nearer to the realization jected disappears during a fraction of MS the cinematograph. A new apparatus ha:. jA animated photography as we now know second. To operate the substitution of tm- recently been invented giving a combina- lt, and which was first commercially and *&& the 900 successive photographs are tion of the cinematograph and the phono- practically illustrated on the appearance of made on a flexible film about fifty-five feet graph tailed the -cronomegaphone,' a /the Edison kinetoscope in 1893. Certain Jong and one and three-eighths inches wide, speech being given the figures as they are defects existed in this machine which were The dimensions of each picture are about thrown on a screen. The Edison kineto- removed in 1895 by Lumiere's cinemato- one inch w 'de and four-fifths inch long, scope is the familiar box seen in the many graph On either side of the film are perforations penny arcades in New York City and about "The working principle of the cinemato- (two holes to each picture) at exact dis- pleasure resorts, and consists of a box con- graph is the persistence of the luminous tances from each other, into which sprock- tabling a roll of films, which are run by impressions upon the retina. If we ob- ets periodically penetrate, with, the object an electnc motor past an incandescent lamp, serve an object, the image in the eye is of pulling the film downward and displac- The electrical and celluloid hazard is in- transmitted to the nervous membrane mg it at each passage of the rotating shut- volved in combination, called the retina. If the object ceases to ter. The sprockets remount immediately The cinematograph and apparatus con- be illuminated suddenly, the image in the in order to attack the next two holes, and nected therewith is a very serious hazard retina is progressively removed, and so so on. and should have intelligent supervision and long as it has not entirely disappeared, the "The cinematograph is composed of two regulation. As the apparatus is installed optic nerve continues to be impressed, and essential mechanical parts—the eccentric m theaters and higher class amusement the eye continues to see the object as if rank and the sprocket frame and sprockets, places with experienced operators, the haz- it had remained illuminated. The duration The rank is manipulated by a handle which ard is reduced to a minimum, but the of the persistence of the luminous im- the operator must turn very regularly 'nickelodeons' and cheap amusement re- pression on the retina varies with the (about two turns per second) ; while the sorts usually combine an uninsurable phy- intensity, duration and color of the light crank rotates once, the eccentric transmis- sical hazard (aside from the bad moral on the object, although It does not con- sion rotates about eight times, or about hazard invariably connected with this class), tinue in full strength for the entire time; sixteen turns per second. The eccentric is Owners of these cheap establishments arv. for a normal illumination it is about 2-45 fixed behind the transmission, and moves in the habit of buying old and worn out second, and is prolonged for another 2-45 the sprockets so as to. engage and disen- machines without modern safeguards, and second, although the illuminated object gage the film. At the end of the crank is placing them in charge of boys and inex- may have disappeared suddenly. Conse- fixed a shutter, which is composed of two penenced and incompetent operators. So quently, if an illuminated object is pre- light metallic sections, which can be regu- many accidents have occurred from these sented to the eye and masked by an opaque lated so as to increase or decrease the size causes that the leading men in the business screen during 1-45 second, for instance, its of the same. There are necessary median- advocate that special laws or ordinances image persists in the eye 1-15 second, and ical parts which it is unnecessary to take be passed in every State or municipality we do not even perceive its passing eclipse, up in detail. The machine should be fitted regulating the exhibiting of moving pic- Let us assume therefore, a number of with magazines for holding the films and tures, and that it be required that operators -photographs on'a film at 1-15 (3-45) sec take-up device for rewinding the film as it be at least twenty years old, and have a ond intervals, showing the successive move- passes through the mechanism after being certain amount of experience and be li- ments of an object; the various pictures ob- projected. censed. Massachusetts now has such a tained are like each other, that is to say, if "The additional apparatus necessary foi law, and the requirements of the Depart- any two thereof are superposed, the parts projecting with the cinematograph is a pro- ment of Electricity of New York City are which represent the fixed objects are ex- jeering lens, an electric lantern resistance quite rigid. The principal hazards .arc actly the same whereas those which corre- coil, a stand and a screen. The cinemato- enumerated under the following heading:' spond with the object in movement occupy graph sets on the front of the stand, with Suggested Safeguards positions of which the displacement has the lamp house in rear and the magazine ; 1U ^c-uards. been accomplished during the time in which for holding the films before projection is Every cinematograph, or other similar two pictures have been taken. located above the machine. The other mag- apparatus involving the use of a combusti- "Now let us assume that we have taken azine is attached to the under side of the ble film, should be inspected and approved 000 successive proofs during a minute, and stand. The resistance coil or rheostat us- by some designated department before be- Iet us project the same o'n a screen by ually sets on the floor near the apparatus, ing placed in operation. It should be re- means of any lantern. Let us eclipse im- Sometimes a calcium or oxy-hydrogen light quired that the films be wound upon a age No I by interposing between the lum- is used instead of electricity. The lantern metal reel inclosed in an iron box having inous source an opaque screen which masks is provided with a condenser, which may be a slot in the bottom only sufficiently large the light during 1-45 second, and, as before a globular glass bottle containing water or to permit the film to pass through the stated the eye will continue to see the pro- a glass condensing lens, which concentrates metal rollers of the projecting mechanism, iected'image not only during the whole of the light of the arc into the projecting ma- and these rollers should fit tightly to the the passage of the opaque screen (or shut- chine. The water globe is decidedly prefer- .film, in order to smother out any flame ter) but even after it has passed, during able to the glass condensing lens, which which might be started outside the cases, the time equal to the difference between has many disadvantages, and especially This iron box or magazine, as it is called, 2-4* second (duration of persistence) and that of concentrating the heat rays on the should be securely made of heavy material 1 at second (duration of the passage of the film when'same is stationary—the water in put together without solder, and the door shutter) that is 1-45 second. Assume, the glass globe absorbs all the heat and the should be a snug fit and provided with a then that a second image has been, substi- power of lighting is increased. The con- spring catch. A similar box to this should tuted for the image No I when the shutter struction of the mechanical pa/ts of the be provided beneath the projecting appa- atrain unmasks the source of light; we still .apparatus must.be extremely exact in all ratus to receive the film after it has been see during 1-45 second image No. 1, evi- its-movements, in order to keep the fragile through the machine; sometimes this box