Silver gelatin photoprocess is a modern photographic process based on the use of photographic gelatin as a binder of photosensitive silver halides . A photoemulsion of this composition is applied to a substrate of glass, paper or flexible film and retains photosensitivity and is suitable for laboratory processing for many years. The process allows for the use of any silver halides, but is often referred to as a dry bromo gelatin emulsion . The technology was developed by Richard Meddox in 1871 and improved by Charles Bennett in 1878 [1] [2] . The process quickly replaced wet collodion , which required exposure and laboratory processing immediately after preparation, greatly complicating photography. The vast majority of modern photographic materials, including color ones, are based on gelatin-silver technology.
Historical background
The previous technology of photography, based on the use of wet collodion , was imperfect, forcing photographers to even carry a traveling darkroom with them on an expedition. At the turn of the 70s and 80s of the XIX century, the English physician Richard Meddox, who was engaged in microphotography , made attempts to replace the uncomfortable collodion, the etheric smell of which was difficult to tolerate [3] . The choice was made on gelatin , which had already been proposed as a binding medium by Victor Nieps and Alfons Puatven [4] . In the dry state, it has high strength, and when wet it swells, freely passing photoreagents to microcrystals. An even more important discovery was the photographic activity of gelatin, as well as the possibility of increasing the photosensitivity of its mixture with silver halide by a thousand times by heating for a certain time [5] [6] . This process, invented in 1878 by Charles Bennett, was called the physical maturation of the emulsion, and made it possible to obtain photographic plates with sensitivity inaccessible to previous technologies [7] . A year later, George Eastman assembled the first machine for pouring a gelatin-silver emulsion onto a glass substrate, establishing the Eastman Dry Plate Company [8] . Subsequently, the company became the world leader in the production of Eastman Kodak photosensitive materials.
The emergence of a new emulsion made a real revolution not only in photography, but also in many other areas. Photographers could now shoot anywhere, taking with them a supply of photographic material that remained usable for many months. Another important innovation was the beginning of the production of photographic materials in an industrial way, whereas before that, photographers made them independently [4] . Dry emulsion gave a start to the creation of cinema , thanks to the appearance of roll film on a flexible substrate and a derivative of film film from them. The structural features of the gelatinous photo layer made it possible to obtain photosensitivity values unattainable for any of the previous technologies. A large role was played by the appearance of amateur cameras with negative roll paper, established by Eastman in 1885 [8] . These box cameras marked the beginning of the development of portable cameras designed for roller film. In 1879, Joseph Swan used a gelatin-silver emulsion for the production of photographic paper with a chemical manifestation [9] [10] . Soon, this led to an almost complete rejection of rapidly fading photo papers with “daylight” - albumin and cellulidine - suitable only for contact printing . In 1894, they began to cover the paper backing with a barite sublayer ( barite ), which prevented the emulsion from seeping between the fibers and increased whiteness. For this reason, gelatin-silver photo paper in everyday life is called "barite" [11] [12] .
Highly sensitive gelatin photo papers ushered in the era of small format photography requiring enlargement [13] . Silver gelatin photo paper was used until it was replaced in the 2000s by digital printing, which was cheaper and did not require complicated laboratory processing. Manual black and white photo printing on paper with a gelatin-silver emulsion has now passed into the category of exclusive technologies, which gallery owners call silver photo printing [14] .
See also
- Collodion process
- Album Seal
Notes
- ↑ Lectures on the history of photography, 2014 , p. 33.
- ↑ Quick reference to amateur photographer, 1985 , p. 13.
- ↑ Stages of the development of photography . The history of photography . Printservice. Date of treatment November 9, 2016.
- ↑ 1 2 Essays on the History of Photography, 1987 , p. 34.
- ↑ Fundamentals of Photographic Processes, 1999 , p. sixteen.
- ↑ Films and their processing, 1964 , p. eight.
- ↑ Soviet Photo, 1971 , p. 40.
- ↑ 1 2 Chemistry and Life, 1988 , p. 34.
- ↑ Essays on the History of Photography, 1987 , p. 38.
- ↑ Photographic paper and photographic processes . Photo Studio "LeopArt". Date of treatment March 26, 2016.
- ↑ Photokinotechnics, 1981 , p. 34.
- ↑ General Photography Course, 1987 , p. 74.
- ↑ Foto & video, 2006 , p. 125.
- ↑ PHOTO. World History, 2014 , p. 555.
Literature
- K.V. Vendrovsky. You press the button - we do the rest (Russian) // " Chemistry and Life ": journal. - 1988. - No. 11 . - S. 30-37 . - ISSN 0130-5972 .
- Alexander Galkin. Bright image (Russian) // “Foto & video”: magazine. - 2006. - No. 4 . - S. 120-125 .
- E.A. Iophis . Chapter I. Films // Films and their processing / V. S. Bogatova. - M.,: “Art”, 1964. - S. 5-12. - 300 s.
- E.A. Iophis . Photokinotechnics. - M .: "Soviet Encyclopedia", 1981. - S. 34. - 449 p. - 100,000 copies.
- Vladimir Levashov . Lectures on the history of photography / Galina Yelshevskaya. - 2nd ed .. - M .: "Trimedia Content", 2014. - 464 p. - ISBN 978-5-903788-63-7 .
- N. D. Panfilov, A. A. Fomin. II. The world's first pictures // A quick reference to amateur photographer. - M .: "Art", 1985. - S. 8-13. - 367 p. - 100,000 copies.
- A.V. Redko. Fundamentals of photographic processes. - 2nd ed .. - St. Petersburg. : "Doe", 1999. - S. 15-17. - 512 s. - (Textbooks for universities. Special literature). - 3000 copies. - ISBN 5-8114-0146-9 .
- Jean Fage. Let us dwell for a moment (Rus.) // “ Soviet Photo ”: magazine. - 1971. - No. 7 . - S. 39-40 . - ISSN 0371-4284 .
- Fomin A.V. Chapter III. Photographic emulsion // General course of photography / T.P. Buldakova. - 3rd. - M.,: "Legprombytizdat", 1987. - S. 62-74. - 256 s. - 50,000 copies.
- K.V. Chibisov . Essays on the history of photography / N. N. Zherdetskaya. - M .: "Art", 1987. - S. 30-37. - 255 p. - 50,000 copies.
- Dictionary // PHOTO. World History / Juliet Hacking. - M.,: “Magma”, 2014. - S. 554–556. - 576 p. - ISBN 978-5-93428-090-2 .