Janssen Revolver
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Janssen Revolver
The Janssen revolver (french: revolver photographique) was invented by the French astronomer Pierre Jules César Janssen in 1874. It was the instrument that originated chronophotography, a branch of photography based on capturing movement from a sequence of images. To create the apparatus Pierre Janssen was inspired by the revolving cylinder of Samuel Colt's revolver. Usage The revolver used two discs and a sensitive plate, the first with twelve holes ( shutter) and the second with only one, on the plate. The first one would take a full turn every eighteen seconds, so that each time a shutter window passed in front of the window of the second (fixed) disk, the sensitive plate was discovered in the corresponding portion of its surface, creating an image. In order for the images not to overlap, the sensitive plate rotated with a quarter of the shutter speed. The Shutter Speed was one and a half seconds. A mirror on the outside of the apparatus reflected the movement of the obje ...
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Black Drop Effect
The black drop effect is an optical phenomenon visible during a transit of Venus and, to a lesser extent, a transit of Mercury. Description Just after astronomical transit#Contacts, second contact, and again just before astronomical transit#Contacts, third contact during the transit, a small black "teardrop" appears to connect Venus's disc to the wikt:limb#Etymology 2, limb of the Sun, making it impossible to time the exact moment of second or third contact accurately. This led to the failure of the attempts during the 18th century transits of Venus to establish a truly precise value for the astronomical unit. The black drop effect was long thought to be due to Venus's thick atmosphere, and indeed it was held to be the first real evidence that Venus had an atmosphere. However, it is now thought by many to be an optical effect caused by the combination of the extreme darkening of the Sun's disk near its apparent edge and the intrinsic imperfection of the viewing apparatus. Ob ...
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Camcorder
A camcorder is a self-contained portable electronic device with video and recording as its primary function. It is typically equipped with an articulating screen mounted on the left side, a belt to facilitate holding on the right side, hot-swappable battery facing towards the user, hot-swappable recording media, and an internally contained quiet optical zoom lens. The earliest camcorders were tape-based, recording analog signals onto videotape cassettes. In 2006, digital recording became the norm, with tape replaced by storage media such as mini-HD, microDVD, internal flash memory and SD cards. More recent devices capable of recording video are camera phones and digital cameras primarily intended for still pictures, whereas dedicated camcorders are often equipped with more functions and interfaces than more common cameras, such as an internal optical zoom lens that is able to operate silently with no throttled speed, whereas cameras with protracting zoom lenses commonly thro ...
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Daguerreotype
Daguerreotype (; french: daguerréotype) was the first publicly available photographic process; it was widely used during the 1840s and 1850s. "Daguerreotype" also refers to an image created through this process. Invented by Louis Daguerre and introduced worldwide in 1839, the daguerreotype was almost completely superseded by 1860 with new, less expensive processes, such as ambrotype ( collodion process), that yield more readily viewable images. There has been a revival of the daguerreotype since the late 20th century by a small number of photographers interested in making artistic use of early photographic processes. To make the image, a daguerreotypist polished a sheet of silver-plated copper to a mirror finish; treated it with fumes that made its surface light-sensitive; exposed it in a camera for as long as was judged to be necessary, which could be as little as a few seconds for brightly sunlit subjects or much longer with less intense lighting; made the resulting lat ...
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Tracking Shot
A tracking shot is any shot where the camera follows backward, forward or moves alongside the subject being recorded. In cinematography, the term refers to a shot in which the camera is mounted on a camera dolly that is then placed on rails – like a railroad track. As a result, this type of shot is often referred to as a dolly shot. A handheld steadycam or gimbal may also be used for smaller scale productions. The camera is then pushed along the track while the scene is being filmed or moved manually when using a handheld rig. The technique is often used to follow a subject that would otherwise leave the frame (ergo, it is often called a following shot), such as an actor or vehicle in motion. In this spirit, any conveyance, such as a motorized vehicle like a car, may also be used to create a tracking shot. A handheld or Steadicam mounted camera following a similar trajectory is called a tracking shot as well. While the core idea is that the camera moves parallel to its subjec ...
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The Horse In Motion
''The Horse in Motion'' is a series of cabinet cards by Eadweard Muybridge, including six cards that each show a sequential series of six to twelve "automatic electro-photographs" depicting the movement of a horse. Muybridge shot the photographs in June 1878. An additional card reprinted the single image of the horse "Occident" trotting at high speed, which had previously been published by Muybridge in 1877. The series became the first example of chronophotography, an early method to photography, photographically record the passing of time, mainly used to document the different phases of locomotion for scientific study. It formed an important step in the development of Film, motion pictures for years to come. Muybridge's work was commissioned by Leland Stanford, the industrialist, former Governor of California, and horseman, who was interested in horse gait analysis. in 1882, Stanford had a book published about the project, also entitled ''The Horse in Motion'', with circa ...
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Eadweard Muybridge
Eadweard Muybridge (; 9 April 1830 â€“ 8 May 1904, born Edward James Muggeridge) was an English photographer known for his pioneering work in photographic studies of motion, and early work in motion-picture projection. He adopted the first name "Eadweard" as the original Anglo-Saxon form of "Edward", and the surname "Muybridge", believing it to be similarly archaic. Born in Kingston upon Thames, England, at the age of 20 he emigrated to the United States as a bookseller, first to New York City, and eventually to San Francisco. In 1860, he planned a return trip to Europe, and suffered serious head injuries in a stagecoach crash in Texas en route. He spent the next few years recuperating in Kingston upon Thames, where he took up professional photography, learned the wet-plate collodion process, and secured at least two British patents for his inventions. He returned to San Francisco in 1867, a man with a markedly changed personality. In 1868, he exhibited large photographs o ...
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Étienne-Jules Marey
Étienne-Jules Marey (; 5 March 1830, Beaune, Côte-d'Or – 15 May 1904, Paris) was a French scientist, physiologist and chronophotographer. His work was significant in the development of cardiology, physical instrumentation, aviation, cinematography and the science of laboratory photography. He is widely considered to be a pioneer of photography and an influential pioneer of the history of cinema. He was also a pioneer in establishing a variety of graphical techniques for the display and interpretation of quantitative data from physiological measurement. Biography Marey started by studying Circulatory system, blood circulation in the human body. Then he shifted to analyzing heart beats, respiration, muscles (myography), and movement of the body. To aid his studies he developed many instruments for precise measurements. For example, in 1859, in collaboration with the physiologist Auguste Chauveau and the watch manufacturer Breguet (brand), Breguet, he developed a wearable ' ...
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French Academy Of Sciences
The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefront of scientific developments in Europe in the 17th and 18th centuries, and is one of the earliest Academy of Sciences, Academies of Sciences. Currently headed by Patrick Flandrin (President of the Academy), it is one of the five Academies of the Institut de France. History The Academy of Sciences traces its origin to Colbert's plan to create a general academy. He chose a small group of scholars who met on 22 December 1666 in the King's library, near the present-day Bibliothèque nationale de France, Bibliothèque Nationals, and thereafter held twice-weekly working meetings there in the two rooms assigned to the group. The first 30 years of the Academy's existence were relatively informal ...
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Société Française De Photographie
The Société française de photographie (SFP) is an association, founded on 15 November 1854, devoted to the history of photography. It has a large collection of photographs and old cameras. Among the founding members were Olympe Aguado, Hippolyte Bayard, Alexandre Edmond Becquerel, Eugène Durieu, Edmond Fierlants, Jean-Baptiste Louis Gros, Gustave Le Gray and Henri Victor Regnault. Henri Victor Regnault was the first president. History The Société française de photographie, founded on 15 November 1854, was based on the short-lived Société héliographique (1851) but differed in that it was less elitist and more forward-looking. Some accounts mistakenly link the two organizations more closely, referring simply to a change in the name with a view to giving the SFP the status of the world's oldest photography organization. A careful analysis of the Société héliographique describes in detail how the initial enthusiasm for the organization quickly disappeared resulting in the ...
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Nagasaki
is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. It became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in the Nagasaki Region have been recognized and included in the UNESCO World Heritage List. Part of Nagasaki was home to a major Imperial Japanese Navy base during the First Sino-Japanese War and Russo-Japanese War. Near the end of World War II, the American atomic bombings of Hiroshima and Nagasaki made Nagasaki the second and, to date, last city in the world to experience a nuclear attack (at 11:02 am, August 9, 1945 'Japan Standard Time (UTC+9)'). , the city has an estimated population of 407,624 and a population density of 1,004 people per km2. The total area is . History Nagasaki as a Jesuit port of call The first contact with Portuguese explorers occurred in 1543. An early visitor was Fernão Mendes Pinto, who came from Sagres ...
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Kepler's Laws Of Planetary Motion
In astronomy, Kepler's laws of planetary motion, published by Johannes Kepler between 1609 and 1619, describe the orbits of planets around the Sun. The laws modified the heliocentric theory of Nicolaus Copernicus, replacing its circular orbits and epicycles with elliptical trajectories, and explaining how planetary velocities vary. The three laws state that: # The orbit of a planet is an ellipse with the Sun at one of the two foci. # A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. # The square of a planet's orbital period is proportional to the cube of the length of the semi-major axis of its orbit. The elliptical orbits of planets were indicated by calculations of the orbit of Mars. From this, Kepler inferred that other bodies in the Solar System, including those farther away from the Sun, also have elliptical orbits. The second law helps to establish that when a planet is closer to the Sun, it travels faster. The third law ex ...
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