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Since the 18th century, the Camera Obscura (Latin for Dark Room) was used, above all by many artists, to capture external images, which would be seen on the opposite wall. The above was nothing more than a simple, rectangular dark box with a small hole in one end and in the more developed case the addition of a lens.
The famous painter Antonio Canal (1697-1768), also known as Canaletto, known for his detailed work, used a "Camera Obscura" to aid him in his drawing.
Photography, as understood by us, originates from the results of numerous experiments carried out both in the optical field, with the planning and development of the Camera Obscura and in that of the chemical field, with the further study of photosensitive materials.
Within a short period of time, the first Camera Obscura was invented much earlier than any procedure for fixing images with chemical products.
The first credible experiments carried out in the chemical field were those of the Frenchman, Joseph Nicéphore Niépce (1765-1833), to whom became awarded the invention of photography.
In 1813, Niepce began to study and perfect the lithographical techniques followed by the interest in the direct registration of his own, real images on lithographical plates.
In 1816, in collaboration with his brother Claude, Niépce managed to obtain the first negative image on various plates sensitised with silver chloride. The first photographic image obtained using this method, on a simple piece of treated paper, depicted a corner of his room. However, the image didn’t result completely fixed and as a result of such, motivated Niépce to research into the use of light sensitive substances.
Niépce discovered that bitumen of Judea under the reaction of light became insoluble in lavender oil obtaining compounds to make photosensitive plates perfectly adaptable to use.
In 1822, after much time and study through experimentation, at the risk of damaging his health due to the mixture of highly toxic substances, arrived the first success, a new photosensitive substance. The reproduction was done on glass and the image was of Padre Pio VII. The plate however was lost.
The most ancient image up until now, is one of those obtained by Niépce in 1926 by means of long exposure using a Camera Obscura in which the lens used was biconvex with a diaphragm and an elementary but effective focusing system. The same Niépce called the image obtained “heliographic”
Despite the notable success obtained by Niépce, after trying to find partners who could have contributed to the success of the project, failed to do so in the attempt of involving The Royal Society.
In 1829, Niépce met Louis-Jacques Mandè Daguerre (1787-1858) well known for the invention of the Diorama and it was Daguerre himself who completed similar experiments such as exposing copper plates to iodine, the fumes forming light sensitive silver iodide all of which helped make his Art of painting easier. The fixing process was that of a warm solution of common salt.
In this same year. Niépce and Daguerre decided to join forces and together developed new techniques for photography.
Only after the death of Niépce in 1833, came about the definite success of photography. In Paris, 1839 at the “Académie des Sciences” in a historical reunion linked to the “Académie des Beaux Arts”, the physicist D.F.Argo demonstrated the new, perfected method of Daguerre.
Despite the fact that the new technique was called “Daguerreotype”, the importance of the discovery was recognised as being that of Niépce and his son, by heritage, who received adequate compensation. The patent was surrendered to the French Government.
Daguerre for his part in the discovery obtained life annuity and other funds from the French government. Daguerre reinvested the proceeds in a small business. By means of direct contact with the United States, Daguerre at the time made thousands of proselytes of the newborn Daguerreotype some with interesting changes.
Daguerreotype remained small pieces of art known for its preciousness and clearness of the image, very similar to that of an etching done by hand. The pictures were all unique and not reproducible.
The news of the new technique soon became of public interest and provoked, in particular, the interest of William Henri Fox Talbot (1800-1877) who was in 1835 already experimenting on a photographic procedure called “Calotype” also known as “Talbotype” which enabled an image to fix itself on sensitive, silver chloride paper from which copies could be reproduced. Such procedure entered into competition with that of Daguerre up until the introduction of Collodion.
At the same time, J.F.Herschel experimented in capturing and retaining images and managed to fix pictures using hyposulphite of soda.
Hippolyte Bayard of Paris had an original idea, which used a sensitive paper negative with silver iodide and obtained successfully positive copies. Bayard was officially asked to avoid direct competition with Daguerre and was not allowed to continue with his experiment and discovery.
The development of “Daguerreotype” was advantaged by the construction of special equipment equipped with an achromatic, meniscus lens introduced by C.L.Chevalier in 1829.
Between 1840 and 1870 as expected, many improvements were made to the methods and materials used for photography. In 1841, A. Claudet gave a new impulse to photography by discovering an accelerating process using chlorine instead of bromine to reduce exposure time by a few seconds.
Changing the face of photography was the development of the wet collodion process introduced by Archer, enabling the making of finely detailed negatives using glass as a base. The new discovery shocked the world of photography. Many legal battles began to defend one’s rights and Talbot himself tried to defend his discovery but was beaten and soon the new collodion process became free to the world replacing the “Calotype” and “Daguerreotype” processes.
Between 1851 and 1852 the new ambrotype and tintype techniques were introduced, procedures through which it was possible to produce direct positives, made by their under-exposing collodion on a glass negative, bleaching it and then placing a black background usually black velvet, occasionally with varnish behind it.
In 1857, appeared the first solar powered enlarger work of J.J. Woodward. In 1859, R. Bunsen and H.E. Roscoe invented the first snapshots using a magnesium lamp. J.C. Maxwell contributed to photography via his studies of colour and in 1861 he demonstrated that by taking three pictures, each through a primary colour filter, and projecting the three using corresponding filters, so that they overlapped, colour pictures could be recreated. In 1868, L Ducos du Hauron made a major contribution to the development of colour photography. He proposed the subtractive method of colour photography.
In 1871, R.L. Maddox suggested a process whereby the sensitising chemicals could be coated on glass plates using a gelatine emulsion instead of wet collodion. In 1873, H. Vogel discovered that if he added appropriate dyes when making a solution, the plates would respond to green light. This led to the manufacture of “orthochromatic” plates.
Following all of the above which can be considered the basics of photography, the research and efforts of scientists and experimenters continued and led to the perfection of sensitive materials, development procedures and optical equipment. Amongst the many important discoveries is obviously the invention of the portable, box camera (1880) and of the roll film made available for the first time in 1888 by George Eastman (1854-1932), founder of the famous company Kodak.
Hurter and Driffield studied film speeds and in 1890 their work plotted image density against logarithm of exposure, producing what became known as “characteristic” curves.
These curves had a straight-line section, which could be extrapolated back to the density axis to give a speed point, used to compare materials. Hurter and Driffield devised the first independent system to give emulsions speed numbers. This led to current ISO numbers on film boxes.
In the meantime many notable advances came about in the optical field where absolutely nothing was left to chance, as the basis of this science is purely mathematical.
Notable merit goes to the German physicist Ernst Abbe who since the beginning worked in close collaboration first with Carl Zeiss (1816-1888) and later his company.
In 1893, when H.D. Taylor projected an anastigmatic lens, so called “triplet of Cooke”, particular due to the fact that it was created with three uncollared lenses. Paul Rudolph later perfected the new lens in 1902 with the introduction of a back collared element.
In 1903, the German firm Zeiss, with this project, put into production this lens which is one of the best products of the photography industry available today; the famous Tessar.
In conclusion, both in the optical field and in that of the photosensitive materials, all that was to be done had been done but the essential, most definite change to photography was the introduction of the film with lateral perforations, 24mm.
Such an ingenious system entered into the world of photography purely by chance, this type of film had been in fact studied at the beginning of the century for cinematography (the lateral perforations were used for dragging the film).
During that era, the light measuring systems were very rough and therefore to avoid great waste of film, a German engineer Oskar Barnack, technician for the company Leitz (well known for their optical production and mechanical devises of precision, invented a small device whereby it was possible to insert pieces of cinematographic film in order to form screen tests from exposure.
In 1913, Leitz put into production a camera designed by Barnack for use with a microscope using modern picture film. This in 1924 became the first 35mm precision camera called Leica.
Thanks to the small format of the film the camera could be built using small dimensions but with the maximum of mechanical precision and gifted also with an excellent viewpoint, eyelet of Leitz.
As a consequence, all the other companies, amongst which Zeiss, projected and built photographic devices using the cinematographic film, which by now was of photographic standard.
After the war and during the 50’s and 60’s, thanks above all to the technological progress, came about many great and relevant improvements such as the introduction of the exposure metre and the reflex view (that is to say via the lens).
The great work directed to change was done by the Japanese and Japanese technicians studied thoroughly German technology introducing electronics and the consequent miniaturization, the electronic dragging of the film and therefore auto-focus (automatic focusing). Naturally from such advances grew the possibility to add accessories together with an endless quantity of different lenses to cover all focal possibilities.
Reflex or Galileian?
The 35mm cameras (size 24x36mm) are divided into two categories: that of the Galilean Viewfinder type camera (a view via a small lateral window) and that of a Single Lens Reflex type (a view via the lens). Both types of model are available either with fixed focal equipment or interchangeable according to the various requirements.
Galilean Viewfinder Type Camera
The Galilean Viewfinder type camera, Leica; has a defect in that it does not allow one to see the exact area to be photographed due to the problem of the parallax, that is to say the stagger which is found between the eye window and lens where the light necessary passes through imprisoning the photo gram.
On the other hand however, the silence, the small dimensions and the optical equipment available, some simple but efficient, are of great value to the camera.
The Single Lens Reflex Type Camera (SLR)
The designers managed to make available this “Reflex” device by inserting behind the lens a mirror whose job it was to reflect the image onto frosted glass placed on the upper part of the device; when a picture was taken, on the click, the mirror lifted itself up allowing light to pass through towards the film.
In 1936 the first 35mm Single Lens Reflex camera was yet again German “Exakta”, the vision came about via the frosted glass and the mirror remained in a raised position up until the next wind up of the shutter. This prevented the continuity of the vision but the biggest fault was that the “Reflex” image appeared upside down. A camera was produced which used a prism to straighten up the image in 1949 and Zeiss made the first Single Lens reflex camera with a pent prism, the Contax S.
Many professional photographers moved from using the Galilean type camera to the Single Lens Reflex one but complained from the beginning due to a blackout which occurred soon after a photograph was taken. This didn’t allow for other photographs to be taken until the shutter had been wound on.
It was the Japanese who along with technicians from Asahi Pentax designed a Reflex camera whereby the mirror returned to its original place immediately after the click. The problem of exposure, which had to be measured by a separate exposure metre, remained. The problem was resolved by Asahi Pentax and Topcon with the introduction of the RE Super model, who in 1963/1964 made available the first Reflex camera with the exposure metre incorporated that read the values of the images from the mirror.
Other evolutions came about with the Olympus OM-2N, which introduced the reading of the values of the images directly from the film during exposure, Konica presented in 1979 the first motorised machine and then in 1984 Olympus introduced the multi spot reader (multiple exposure) with the OM4.
Nikon, Canon and Minolta studied new systems for auto focus (automatic focusing) to obtain, up until today, by Canon, the “stabilization” of the lens.
The End
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