The Cine Technician (1939)

June-July, 193; THE CINE-TECHNICIAN treated as of any importance nor was there any idea of the link it would be in photographic art. Years passed by, and a German physician, Schultze, in 1727 carried out an experiment with a mixture of chalk and silver nitrate. He used to cut out designs in cardboard, place them over the mixture and expose them to the sunlight, after which the design appeared in black upon his mixture of chalk and silver nitrate. A Dr. William Lewis repeated this experiment in England in 1763. At his death his records were bought by Josiah Wedgwood, the potter. He also made many interesting experiments with silver salts. He was later assisted by Sir Humphrey Davy, and between them they coated paper with a weak solution of silver salts. They placed opaque objects to cast shadows over the prepared surface, resulting in the paper turning black, except where the shadows were cast ; thus they succeeded in securing a print of the objects on a black ground. They also tried their prepared paper with the camera obscura, with no success, owing no doubt to the lack of intensity of the light, their paper being coated only with such a weak solution of silver salts. They were never able to fix any <5f their results. Nevertheless, this was at least another step forward towards the real invention of photography. % ^ % A little more than a hundred years ago, several men in many countries were striving to capture "pictures painted by light" and retain them permanently (it was an art in those days to trace the images of scenes on a piece of paper caused by the camera obscura) ; and it was the pioneering work, energy, invention and sometimes accidental discoveries of men like Daguerre and Niepce in France and Fox Talbot in England (who eventually mated the picture caused by the camera obscura with a sensitive surface that was affected by light and by chemical treatment) that resulted in the image being permanently retained. Niepce discovered that a mineral substance known as bitumen of Judea (a sort of asphalt or pitch) , when dissolved with some oils, was affected by exposure to light, an exposure in sunlight lasting many hours. He spread his preparation of bitumen on a tablet of plated silver or wellcleaned glass. This was very similar to the method Wedgwood and Davy had used, of paper soaked in silver salts. Daguerre and Niepce entered into partnership, and Daguerre (who had also been experimenting with silver salts) made many improvements in Niepce's process. Daguerre, however, soon became dissatisfied with the long exposure necessary, and earnestly sought after some quicker process. It is interesting to note that Niepce called his process "heliography" or sun-drawing. He died in 1833, and his son joined Daguerre in the partnership. The following paragraphs I quote from Mr. Charles R. Gibson's book, "Romance of Modern Photography" ; they are extremely interesting at this juncture :— "Daguerre had abandoned the bitumen process of his late partner, Niepce, as also his early experiments with silver salts, but lie was evidently seeking once more to engage silver, in some form or other, in his service. It is said that Daguerre accidentally discovered that a plate treated with iodine was sensitive to light. We are told that on one occasion he noticed that a plate which had been treated with iodine retained the image of a silver spoon which had chanced to be laid down upon it. Although I can only find one historian who has preserved this tale for us, it seems a very probable one. Daguerre had already seen Niepce use iodine to blacken his bitumen pictures, so that iodine would be sure to be among Daguerre's stock of chemicals. It would be quite natural thai he should try to improve his own pictures l>v exposing them to the vapour of iodine, just as Niepce had done, and no doubt it would be upon a plate which he had thus treated that he accidentally discovered the image of a spoon. This would suggest to him at once that iodine would make his silver plate sensitive to light. "This iodine with which Daguerre was working had not long been discovered. It is an elementary substance and was obtained by some chemical manufacturers from seaweed. Daguerre took a brightly polished plate of silver and sought to make its surface sensitive to light by exposing it to the vapour of iodine. Alas, when Daguerre expos< d his plate in the camera, lie could only get a faint sort of N° 10,131 A.D. 1889 Dale 0/ Application, 21st June, 1889 Complete Specification Left, 13th Mar., 1890— Accepted, Wth May, 1890 PROVISIONAL SPECIFICATION. Improved Apparatus for Taking Photographs in Rapid Series We, William Friese Gkeene, Photographer, of 92, Piccadilly, in the County of London, aod Mortimer Evans, Civil Engineer, of Savile Club, Piccadilly aforesaid, do hereby declare the nature of this invention to be as follows : — Our Invention has for its objeot the formation of Photographic Pictures, and 5 relates chiefly to the production of such pictures as are neces-ary to illustral i and register the movements of animals, insects or moving objects either taken singly or in masses as may be desired. For this purpose we construct an apparatus by which with a single camera and lens a rapid series of such pictures mav be taken and by which a serie9 ol fresh 10 photographic sensitive films or portions of such photographic film may be substituted for those which have been exposed to the action of light with sufficient rapidity tor the desired end. To carry out our Invention we provide a main shaft which is actuated either by a winch turned by hand, clock-work or otherwise, to this shaft is attached wheel 15 work and counter shafts by which the whole apparatus is driven ami the ne(.-..--ury cycle of motions performed. By the rotation of this shaft the prepared film is paid out and pi I in position to receive the photographic impression and it is then automatically exposed to the action of light, the light is then cut off, and the exposed film i passed nn and wound 20 up on a receiving roller, fresh film being at the same time paid out to receive the succeeding impression which is after exposure again passed on and wound up as before. All these movements go on so long as tli" main shaft is rotated and there is film on which to operate, the number of such pictures being limited alone by the length or amount of film provided. 25 To provide for the production of many pictures such as would constitute a lengthened series of such pictures and to enable three hundred "r more to be taken successively and in rapid series, we arrange a long roll of sensitive photographic him on one of the spindles or counter-shafts before montioned and this spindle is so arranged that as it rotates under the driving action of the main shaft it pays nut 30 the film as fast as it is needed. To another spindle or counter shaft the fn rid of the film is attached, and the arrangement is such that by means of the main shaft this second counter shaft is caused to rotate in a reverso direction to that ol the former or paying ont spindle and its action consequently is to wind the film ap is fast as it is paid out. 35 Intermediate of these two rollers or counter shafts we arrange an exposure screen over which the sensitive film passes on its *\vay to the rolling up shaft and it is whilst the film rests on this exposure screen that it is subjected to the actiop ot the phatographie image. As both paying out and rolling up rollers have a continuous motion communicated 40 to them by the driving shaft, and as it is desirous that the film during its exposure to the light should be at rest we provide an arrangement to effect this which is as follows. Immediately heyond the exposure screen and between it ani the upwinding roller we place an intermittently acting drum of such a diameter and circumference as that each turn thereof will take up or roll forward the exact 45 amount of film that is required for each picture, and in passing this film foi .vai I the drum also draws into the exposure position a fresh length of film ready to be exposed. To effect this intermittent motion we provide the aforesaid drum with a single long escapement tooth which when the drnm is not in motion rests on the cylindrical u PRICE ) Facsimile reproduction of front page of William Friese-Grecne Patent, June 1889, reproduced by kind permission of the Controller of H.M. Stationery Office. image of bright objects, and that after in, my hours of exposure. It seemed as though the hopes that he had built upon his silver plate, with its coating of iodine of silver, were going to share the same fate as his earliei experiments with paper soaked in silver salts ; indeed matters looked even more hopeless. "It so happened that one clay he removed one of these silver plates from his camera, as the exposure, probably due to the light, had been insufficient to produce any image. Had the spoilt plate been a glass one or a prepared paper it would doubtless have been immediatelj consigned