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Photographic plate

From Wikipedia, the free encyclopedia
AGFAphotographic plates, 1880
Mimosa Panchroma-Studio-Antihalo Panchromatic glass plates, 9 x 12cm, Mimosa A.-G. Dresden
Negative plate

Photographic platesprecededphotographic filmas a capture medium in photography. The light-sensitiveemulsionofsilver saltswas coated on aglass plate,typically thinner than common window glass. They were heavily used in the late 19th century and declined through the 20th. They were still used in some communities until the late 20th century.

History[edit]

Glass plates were far superior to film for research-quality imaging because they were stable and less likely to bend or distort, especially in large-format frames for wide-field imaging. Early plates used the wetcollodion process.The wet plate process was replaced late in the 19th century bygelatindry plates.

Image resulting from a glass plate negative showing Devil's Cascade in 1900.

Aview cameranicknamed "The Mammoth" weighing 1,400 pounds (640 kg) was built byGeorge R. Lawrencein 1899, specifically to photograph "TheAlton Limited"train owned by theChicago & Alton Railway.It took photographs on glass plates measuring 8 feet (2.4 m) × 4.5 feet (1.4 m).[1]

Glass plate photographic material largely faded from the consumer market in the early years of the 20th century, as more convenient and less fragile films were increasingly adopted. However, photographic plates were reportedly still being used by one photography business in London until the 1970s,[2]and by one in Bradford called the Belle Vue Studio that closed in 1975.[3]They were in wide use by the professionalastronomicalcommunity as late as the 1990s. Workshops on the use of glass plate photography as an alternative medium or for artistic use are still being conducted.

Sizes
Known as Imperial Metric
Quarter-plate 3¼ × 4¼ in. 83mm × 108mm
Half-plate 4¾ × 6½ in. 120mm × 165mm
Full-plate 6½ × 8½ in. 216mm × 165mm

Scientific uses[edit]

Astronomy[edit]

Many famousastronomical surveyswere taken using photographic plates, including the firstPalomar ObservatorySky Survey (POSS) of the 1950s, the follow-up POSS-II survey of the 1990s, and the UKSchmidtsurveyof southerndeclinations.A number ofobservatories,includingHarvard CollegeandSonneberg,maintain large archives of photographic plates, which are used primarily for historical research onvariable stars.

Many solar system objects were discovered by using photographic plates, superseding earlier visual methods. Discovery ofminor planetsusing photographic plates was pioneered byMax Wolfbeginning with his discovery of323 Bruciain 1891. The firstnatural satellitediscovered using photographic plates wasPhoebein 1898.Plutowas discovered using photographic plates in ablink comparator;its moonCharonwas discovered 48 years later in 1978 byU.S. Naval ObservatoryastronomerJames W. Christyby carefully examining a bulge in Pluto's image on a photographic plate. [4]

Glass-backed plates, rather than film, were generally used in astronomy because they do not shrink or deform noticeably in the development process or under environmental changes. Several important applications ofastrophotography,includingastronomical spectroscopyandastrometry,continued using plates untildigital imagingimproved to the point where it could outmatch photographic results.Kodakand other manufacturers discontinued production of most kinds of plates as the market for them dwindled between 1980 and 2000, terminating most remaining astronomical use, including for sky surveys.[5]

Physics[edit]

Photographic plates were also an important tool in earlyhigh-energy physics,as they are blackened byionizing radiation.Ernest Rutherfordwas one of the first to study the absorption, in various materials, of the rays produced inradioactive decay,by using photographic plates to measure the intensity of the rays. Development of particle detection optimisednuclear emulsionsin the 1930s and 1940s, first in physics laboratories, then by commercial manufacturers, enabled the discovery and measurement of both thepi-mesonandK-meson,in 1947 and 1949, initiating a flood of new particle discoveries in the second half of the 20th century.[6]

Electron microscopy[edit]

Photographic emulsions were originally coated on thin glass plates for imaging withelectron microscopes,which provided a more rigid, stable and flatter plane compared to plastic films.[7]Beginning in the 1970s, high-contrast, fine grain emulsions coated on thicker plastic films manufactured by Kodak, Ilford and DuPont replaced glass plates. These films have largely been replaced by digital imaging technologies.[8]

Medical imaging[edit]

The sensitivity of certain types of photographic plates to ionizing radiation (usuallyX-rays) is also useful inmedical imagingandmaterial scienceapplications, although they have been largely replaced with reusable and computer readableimage platedetectors and other types ofX-ray detectors.

Decline[edit]

The earliest flexible films of the late 1880s were sold for amateur use in medium-format cameras. The plastic was not of very high optical quality and tended to curl and otherwise not provide as desirably flat a support surface as a sheet of glass. Initially, a transparent plastic base was more expensive to produce than glass. Quality was eventually improved, manufacturing costs came down, and most amateurs gladly abandoned plates for films. After large-format high quality cut films for professional photographers were introduced in the late 1910s, the use of plates for ordinary photography of any kind became increasingly rare.

The persistent use of plates in astronomical and other scientific applications started to decline in the early 1980s as they were gradually replaced bycharge-coupled devices(CCDs), which also provide outstanding dimensional stability. CCD cameras have several advantages over glass plates, including high efficiency, linear light response, and simplified image acquisition andprocessing.However, even the largest CCD formats (e.g., 8192 × 8192 pixels) still do not have the detecting area andresolutionof most photographic plates, which has forced modern survey cameras to use large CCD arrays to obtain the same coverage.

The manufacture of photographic plates has been discontinued by Kodak, Agfa and other widely known traditional makers. Eastern European sources have subsequently catered to the minimal remaining demand, practically all of it for use inholography,which requires a recording medium with a large surface area and a submicroscopic level of resolution that currently (2014) available electronic image sensors cannot provide. In the realm of traditional photography, a small number of historical process enthusiasts make their own wet or dry plates from raw materials and use them in vintage large-format cameras.

Preservation[edit]

Several institutions have established archives topreserve photographic platesand prevent their valuable historical information from being lost. The emulsion on the plate can deteriorate. In addition, the glass plate medium is fragile and prone to cracking if not stored correctly.[9]

Historical archives[edit]

The United StatesLibrary of Congresshas a large collection of both wet and dry plate photographic negatives, dating from 1855 through 1900,[10]over 7,500 of which have been digitized from the period 1861 to 1865.[11] TheGeorge Eastman Museumholds an extensive collection of photographic plates.[12][failed verification]In 1955, wet plate negatives measuring 4 feet 6 inches (1.37 m) × 3 feet 2 inches (0.97 m) were reported to have been discovered in 1951 as part of theHoltermann Collection.These purportedly were the largest glass negatives discovered at that time.[13]These images were taken in 1875 byCharles Bayliss[14]and formed the "Shore Tower" panorama[15]of Sydney Harbour.[13]Albumen contact prints made from these negatives are in the holdings of the Holtermann Collection, the negatives are listed among the current holdings of the Collection.[14][16]

Scientific archives[edit]

Preservation of photographic plates is a particular need in astronomy, where changes often occur slowly and the plates represent irreplaceable records of the sky and astronomical objects that extend back over 100 years. The method of digitization of astronomical plates enables free and easy access to those unique astronomical data and it is one of the most popular approaches to preserve them. This approach was applied at theBaldone Astrophysical Observatorywhere about 22,000 glass and film plates of theSchmidt Telescopewere scanned and cataloged.[17]Another example of an astronomical plate archive is the Astronomical Photographic Data Archive (APDA) at thePisgah Astronomical Research Institute(PARI). APDA was created in response to recommendations of a group of international scientists who gathered in 2007 to discuss how to best preserve astronomical plates (see the Osborn and Robbins reference listed under Further reading). The discussions revealed that some observatories no longer could maintain their plate collections and needed a place to archive them. APDA is dedicated to housing and cataloging unwanted plates, with the goal to eventually catalog the plates and create a database of images that can be accessed via the Internet by the global community of scientists, researchers, and students. APDA now has a collection of more than 404,000 photographic images from over 40 observatories that are housed in a secure building with environmental control. The facility possesses several plate scanners, including two high-precision ones, GAMMA I and GAMMA II, built for NASA and the Space Telescope Science Institute (STScI) and used by a team under the leadership of the late Barry Lasker to develop the Guide Star Catalog and Digitized Sky Survey that are used to guide and direct theHubble Space Telescope.APDA's networked storage system can store and analyze more than 100 terabytes of data.[18]

A historical collection of photographic plates fromMt. Wilson observatoryis available at theCarnegie Observatories.[19]Metadata is available via a searchable database,[20]while a portion of the plates has been digitized.

See also[edit]

References[edit]

  1. ^"The Largest Photograph in the World of the Handsomest Train in the World"(PDF).Chicago & Alton Railway. Archived fromthe original(PDF)on 7 February 2016.Retrieved30 January2016.
  2. ^"Harrow Photos – History of the Hills & Saunders Photographic Collection".Harrow School.Archived fromthe originalon 17 April 2009.Retrieved8 February2016.
  3. ^"Belle Vue Studio - Photo Archive - Bradford Museums & Galleries".
  4. ^"Charon Discovery Image – Galleries – NASA Solar System Exploration".NASA Solar System Exploration.Archived fromthe originalon 30 January 2016.Retrieved21 January2016.
  5. ^Girard, Terrence M.; Dinescu, Dana I.; Van Altena, William F.; Platais, Imants; Monet, David G.; López, Carlos E. (2004). "The Southern Proper Motion Program. III. A Near-Complete Catalog toV= 17.5 ".The Astronomical Journal.127(5): 3060.arXiv:astro-ph/0402411.Bibcode:2004AJ....127.3060G.doi:10.1086/383545.S2CID15153001.
  6. ^Herz, A.J.; Lock, W.O. (May 1966)."Nuclear Emulsions".CERN Courier.6:83–87.
  7. ^Dykstra, Michael J.; Reuss, Laura E. (2003).Biological electron microscopy: theory, techniques, and troubleshooting(2nd ed.). New York, NY: Kluwer Academic. p. 194.ISBN978-0306477492.Retrieved21 January2016.
  8. ^Fan, G. Y.; Ellisman, M. H. (1 October 2000). "Digital imaging in transmission electron microscopy".Journal of Microscopy.200(Pt 1): 1–13.doi:10.1046/j.1365-2818.2000.00737.x.ISSN0022-2720.PMID11012823.S2CID2034467.
  9. ^Gillett, Martine; Garnier, Chantal; Flieder, Francoise (1986). "Glass plate negatives. Preservation and restoration".Restaurator.7(2): 49–80.doi:10.1515/rest.1986.7.2.49.S2CID93161043.
  10. ^"Civil War Glass Negatives and Related Prints".U.S. Library of Congress.Retrieved6 April2016.
  11. ^"Civil War Glass Negatives and Related Prints".United States Library of Congress.Retrieved6 April2016.
  12. ^"Conservation".George Eastman Museum.Retrieved23 March2016.
  13. ^ab"Australia's Holtermann collection of wet plate negatives"(PDF).Journal of Photography of the George Eastman House.4(3): 6–8. March 1955. Archived fromthe original(PDF)on 9 September 2015.Retrieved23 March2016.
  14. ^ab"Panorama of Sydney and the Harbour, New South Wales".Art Gallery of New South Wales.Retrieved24 March2016.
  15. ^"Holtermann panorama"(PDF).National Gallery of Australia.Retrieved24 March2016.
  16. ^"Three glass plate negatives of Sydney Harbour from the Holtermann residence, St. Leonards".State Library of New South Wales Catalogue.Retrieved7 April2016.
  17. ^Ilgmars Eglitis and Vitaly Andruk (June 2017)."Processing of Digital Plates 1.2m of Baldone Observatory Schmidt Telescope".Open Astronomy.26(1): 7–17.Bibcode:2017OAst...26....1N.doi:10.1515/astro-2017-0002.
  18. ^"ADPA".
  19. ^"Plate Archive Search Tool (PAST)".Carnegie Observatories.Retrieved2020-12-16.
  20. ^"Carnegie Observatories Plate Archive Database".plates.obs.carnegiescience.edu.Retrieved2021-01-07.

Further reading[edit]

  • Peter Kroll, Constanze La Dous, Hans-Jürgen Bräuer:"Treasure Hunting in Astronomical Plate Archives." (Proceedings of the international Workshop held at Sonneberg Observatory, March 4 to 6, 1999.)Verlag Herri Deutsch, Frankfurt am Main (1999),ISBN3-8171-1599-7
  • Wayne Osborn, Lee Robbins:"Preserving Astronomy's Photographic Legacy: Current State and the Future of North American Astronomical Plates."Astronomical Society of the Pacific Conference Series, Vol. 410 (2009),ISBN978-1-58381-700-1
  • Pisgah Astronomical Research Institute (PARI) Astronomical Photographic Data Archive (APDA)https:// pari.edu/research/adpa/

External links[edit]

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