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Glass plates were far superior to film for research-quality imaging because they were extremely stable and less likely to bend or distort, especially in large-format frames for wide-field imaging. Many famous astronomical surveys were taken using photographic plates, including the first Palomar Observatory Sky Survey (POSS) of the 1950s, the follow-up POSS-II survey of the 1990s, and the UK Schmidt survey of southern declinations. Many observatories, including Harvard University and Sonneberg Observatory , maintain large archives of photographic plates, primarily for historical research on variable stars.

Photographic plates were also an important tool in early high-energy physics, as they get blackened by ionizing radiationIonizing radiation is radiation in which an individual particle (for example, a photon, electron, or helium nucleus) carries enough energy to ionize an atom or molecule (that is, to completely remove an electron from its orbit). If the individual particle. For example, Victor Franz Hess discovered, in the 1910sCenturies: 19th century 20th century 21st century Decades: 1860s 1870s 1880s 1890s 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 Events and trends Technology John Alcock and Arthur Whitten Brown make first non, cosmic radiation as it left traces on stacks of photographic plates, which he for that purpose brought up on high mountains or let mount into the even higher atmosphere using ballooncards or flowers. A balloon is a flexible bag normally filled with air or gas. Some balloons are purely decorative, while others are used for specific purposes. Early balloons were made of dried animal bladders. Balloons as flying machines Large balloonss.

Use of photographic plates has declined significantly since the 1990s, replaced by charge-coupled deviceA charge-coupled device CCD , is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to one or other of its neighbours. CCDs are used in digs (CCD). CCD cameras have several benefits over glass plates, including highly efficient, linear response to light, and simplicity of image acquisition and processingDigital image processing is the study of algorithms applied to digital images. Typical problems covered by this field include geometric transformations such as enlargement, reduction, and rotation; color corrections such as brightness and contrast adjustm. However, even the largest format CCDs (e.g. 8192x8192 pixels) still do not have the resolutionThe image resolution is a term that says something about how much image detail an image can hold. The term is most often used in relation to digital images, but is also used to describe how grainy a "film-based" image is. Higher resolution means more imag of most photographic plates, and the longevity of electronic data and data formats (such as FITS) is uncertain.