PhotoHistory

From: PHOTOGRAPHY OF TO-DAY

By H. CHAPMAN JONES, 1913

The Development of Photography (part 3 of 3)

Niepce and Daguerre

The next two men that we have to refer to, worked at the perfection or discovery of a photographic process with an unprecedented perseverance. They are the first men who really devoted themselves to the matter. Joseph Nicephore Niepce was born at Chalons-sur-Saone in 1765, six years before Thomas Wedgwood was born, educated for the Church, but at the time of the French revolution became a soldier. After this he settled down at his birthplace and indulged his scientific tastes. In 1815, or about then, he began his photographic experiments with the idea of finding if possible a method of automatically copying designs upon lithographic stones, so as to save the tedious work of the draughtsman. Lithography was a comparatively new art at that time, and was just beginning to be appreciated in France. From the stone, he passed eventually to tin, pewter, silver, and even glass. The sensitive substance that he was most successful with was bitumen or asphalte, which he dissolved to form a varnish and then applied so as to obtain a film on the surface to be treated. This film of varnish when exposed to light would show no sign of change, but where the light acted it would become less soluble, so that on applying a weak solvent, such as a mixture of oil of lavender and petroleum oil, the parts that were not changed by the action of the light would dissolve more readily than the other parts, and with due care a good picture would be obtained, the varnish left on the plate corresponding to the light or white parts of the subject. Niepce succeeded in getting pictures in the camera with six or eight hours exposure, and he could copy a transparent print laid direct upon the plate and exposed to light in about two hours. Some of these pictures on metal he put into acid that dissolved or etched the metal where it was not protected by the varnish, and from these he got prints by the ordinary method of the printing press. The pictures produced on silver showed the reddish varnish in the parts corresponding to the bright parts of the object, and the white metal corresponding to the dark parts or shadows. He tried to darken the metal where it was exposed to make the appearance more natural, and the substance that he was the most successful with for this purpose was iodine, which does darken silver very effectually. The varnish could then be dissolved away, and now the white silver would represent the lights and the darkened silver the dark parts of the object or print.

Thus Niepce was eminently successful from an experimental point of view, for he not only got his pictures, even those produced in the camera, but he succeeded in fixing them, using the word “fix” in its present-day sense, and those of his pictures that have been taken care of show little or no deterioration. Moreover he produced invisible images which he developed.

Louis Jacques Mande Daguerre was twenty-two years the junior of Niepce and a very different sort of man. He was born near Paris, and was perhaps the most celebrated scene-painter who has ever lived. He was not only successful as a man of business, but he was ingenious and original in his methods. He used a camera obscura to help him in his painting, and about the year 1824 was moved with a desire to try to “fix” the camera image. We do not know what gave rise to this desire, whether he hoped that it would help him in his drawing, or whether, as seems more likely, he thought that if successful the production of pictures in this way would excite the interest of the public and be profitable to him. He seems to have been working with phosphorescent substances, that is substances which when illuminated continue to shine after the light that illuminates them is withdrawn. Perhaps he hoped to get self-luminous pictures in this way, for we know that he was original and successful in the manner in which he illuminated his dioramas. Charles Chevalier, who was a maker of optical instruments and had a shop in Paris, used to supply Daguerre with apparatus, and he knew the direction in which he was working. In 1826, either Niepce or his father went to Chevalier’s to see about getting a camera, and in this way Chevalier came to know of Niepce’s success. He told Daguerre of this, and Daguerre immediately wrote to Niepce on the subject. Niepce was reticent and cautious, but Daguerre was genial and persevering, and the result was that in 1829 the two men entered formally into partnership. According to the agreement, Niepce told Daguerre how he had succeeded, and in return Daguerre contributed some detail with regard to an improvement in his camera. Daguerre, the pushful and younger man, seems to have had the best of the bargain, but Niepce had been disappointed that his results, which he brought also to this country, awakened practically no interest, even among scientific men. Niepce was now sixty-four years old, and four years after this he died.

Daguerreotype

Niepce used iodine to blacken the silver plate, as already stated, after he had got his photograph, and it was doubtless this that led Daguerre to work with silver darkened on its surface by iodine fumes. But Daguerre used this darkened silver surface as the sensitive surface, which Niepce appears never to have done. By 1837, Daguerre had by sheer perseverance, so great that his wife had doubts as to his sanity, brought the Daguerreotype process to a practical form. He and Niepce’s son, Isidore, endeavored to put the process on a commercial footing, but the incredulity and indifference of others they could not overcome. Probably as a last resource Daguerre went to Arago, the most celebrated scientific man in France, and he saw enough of the possibilities of the process to become enthusiastically interested in it. Through Arago’s influence Daguerre and the younger Niepce were given substantial pensions by the French Government on condition that they published the details of the process, and this was done in 1839. The process consisted in exposing the polished surface of a silvered copper plate to the fumes of iodine until it was coated with a compound of silver and iodine. The plate was exposed in the camera, and then developed by putting it over a dish of gently warmed mercury. The mercury vapor deposited on those parts where the light had acted, but not on the other parts. Where the light had acted to a small extent, there was a correspondingly small deposition of mercury, so that the lights and shades were well reproduced. The silver iodide was then dissolved away by hyposulphite of soda, just as negatives and silver prints are fixed at the present day.

Daguerreotype was the first method of photography available for practical purposes. As soon as the necessary details could be obtained a great many persons took up the process. The plates were eventually made more sensitive by the use of bromine in addition to the iodine, and other improvements were effected; and Petzval devised his portrait lens, which still further reduced the very long exposures at first necessary. Daguerreotypists gradually increased in number in practically all parts of the civilized world, and photography became a “profession.” So far as the general public were concerned the process had no rival until after 1851, the year in which Daguerre died and the collodion process first saw the light. A few years after this the Daguerreotype process became practically obsolete.

Talbot, Herschel and Reade

The announcement of Daguerre’s success in 1839, coming with the stamp of the authority of the French Government, at once attracted attention. Indeed before it was announced some preliminary information was circulated, and this urged into increased activity others who were seeking to make photography practical. W. H. Fox Talbot, who had been working on similar lines to Wedgwood and Davy, sent two communications to the Royal Society early in 1839 showing that he had obtained a much greater sensitiveness than the earlier workers and had succeeded in “fixing” the result. He used silver chloride for his sensitive substance, impregnated paper with it for use, and fixed either with a weak solution of potassium iodide or a strong solution of common salt. Three weeks after this Sir John Herschel, who had heard seven weeks before that Daguerre had a successful process ready to be made public, accepted the statement “as an enigma to be solved,” and finding silver chloride on paper lacking in sensitiveness used nitrate of silver. For removing the unaltered silver compound after the exposure in order to fix the photograph, he used a hyposulphite, which he had previously recommended for this purpose. He made not only what we now call negatives, but also “second transfers,” as he called them, or what we now understand as prints or positives. He showed twenty-three photographs, “one, a sketch of his telescope at Slough, fixed from its image in a lens; and the rest copies of engravings and drawings.” There was one other worker of note who brought forward his results at this time, namely the Rev. J. B. Reade, a scientific man of a retiring disposition, who appears to have been the only one that really sought to follow up the experiments of Wedgwood. Early in 1837 he was anxious to save the cost of an artist for drawing the magnified pictures that he projected on a screen by means of his microscope, using either sunshine or the oxy-hydrogen light, and so endeavored to get photographic impressions. As Wedgwood and Davy had found that leather gave a more sensitive surface than paper when impregnated with the silver salt, he used light colored leather gloves until the supply failed. Then he said “I will tan paper.” For this purpose he applied an infusion of galls to the paper in addition to the silver salt, and so obtained a greatly enhanced sensitiveness. He obtained a photograph of a flea by means of his microscope in less than five minutes, and sections of wood were photographed with an exposure of from eight to ten minutes. The sensitive paper so prepared could be used in the camera. Reade used sodium hyposulphite for dissolving away the unaltered silver salt.

Two years later, Fox Talbot effected a very great advance in the sensitiveness of his paper, making it more than a hundred times as sensitive as any known before, he says. He had accidentally discovered that it was possible to produce with silver compounds a latent or invisible impression that could afterwards be developed. Both Daguerre and Niepce developed their photographs from invisible images, but this kind of development appears to be radically different, as we shall see in detail when we come to consider the subject. In this process of Fox Talbot’s, which was called “calotype,” paper was impregnated with silver iodide, and shortly before use washed over with a mixed solution of silver nitrate and gallic acid. After exposure in the camera no change was visible, but after removal, if the paper was washed over with more of the gallic acid and silver solution and gently warmed before the fire, the image gradually appeared and grew to an intense blackness. With an ordinary slow view lens one minute’s exposure would suffice for a building in sunshine, and with a rapid portrait lens a white bust in sunshine needed only one second to produce an impression that would satisfactorily develop. From these negatives Fox Talbot made prints in much the same way as they are made at the present time.

Niepce de Saint Victor and Archer

So far it will be observed that the sensitive silver compounds used were either on a metal plate or on and more or less in the substance of a sheet of paper. In 1848, Niepce de Saint Victor, nephew of the first Niepce, used a film of albumen supported on glass to hold the sensitive compound, that is a transparent film. In 1851 Frederick Scott Archer published a process in which collodion was used instead of albumen. But this is a process that still survives, and therefore must receive more detailed attention later on.

We have thus traced photography with silver salts from its earliest beginning so far as concerns the most important stages in its development. The later history will appropriately be referred to, so far as we are able, in connection with the subjects to which the details specifically refer. But if all the historical facts mentioned in this volume were brought together, they would not constitute anything like a complete history of the subject. There were other workers besides those mentioned, before 1839, and since then there have been very many indeed. They have been of all kinds, from the most learned scientific men to those who knew nothing of scientific method and hardly more of what we understand as scientific facts. They have been from the wealthiest to the poorest. Some have worked for practical results only, some for personal profit, and some rather to elucidate a theory or to discover the exact nature of the changes that take place. Photography is so varied in its methods and its applications that it may be regarded from many points of view.