Camera obscura


Camera obscura
Camera obscura box.jpg
Cameras obscurae for Daguerreotype called "Grand Photographe" produced by Charles Chevalier (Musée des Arts et Métiers)

The camera obscura (Latin; "camera" is a "vaulted chamber/room" + "obscura" means "dark"= "darkened chamber/room") is an optical device that projects an image of its surroundings on a screen. It is used in drawing and for entertainment, and was one of the inventions that led to photography. The device consists of a box or room with a hole in one side. Light from an external scene passes through the hole and strikes a surface inside where it is reproduced, upside-down, but with color and perspective preserved. The image can be projected onto paper, and can then be traced to produce a highly accurate representation.

Using mirrors, as in the 18th century overhead version (illustrated in the History section below), it is possible to project a right-side-up image. Another more portable type is a box with an angled mirror projecting onto tracing paper placed on the glass top, the image being upright as viewed from the back.

As a pinhole is made smaller, the image gets sharper, but the projected image becomes dimmer. With too small a pinhole the sharpness again becomes worse due to diffraction. Some practical camera obscuras use a lens rather than a pinhole because it allows a larger aperture, giving a usable brightness while maintaining focus. (See pinhole camera for construction information.)

Contents

History

The first surviving mention of the principles behind the pinhole camera, a precursor to the camera obscura, belongs to Mo-Ti (470 BC to 390 BC), a Chinese philosopher and the founder of Mohism.[1] Mo-Ti referred to this camera as a "collecting plate" or "locked treasure room".[2] The Greek philosopher Aristotle (384 to 322 BC) understood the optical principle of the pinhole camera.[3] He viewed the crescent shape of a partially eclipsed sun projected on the ground through the holes in a sieve, and the gaps between leaves of a plane tree.

The camera obscura was known to earlier scholars since the time of Mozi and Aristotle.[4] Euclid's Optics (ca 300 BC), presupposed the camera obscura as a demonstration that light travels in straight lines.[5]

In the 4th century BC, Aristotle noted that "sunlight travelling through small openings between the leaves of a tree, the holes of a sieve, the openings wickerwork, and even interlaced fingers will create circular patches of light on the ground." In the 4th century AD, Theon of Alexandria observed how "candlelight passing through a pinhole will create an illuminated spot on a screen that is directly in line with the aperture and the center of the candle." In the 9th century, Al-Kindi (Alkindus) demonstrated that "light from the right side of the flame will pass through the aperture and end up on the left side of the screen, while light from the left side of the flame will pass through the aperture and end up on the right side of the screen."

In the 6th century, Byzantine mathematician and architect Anthemius of Tralles (most famous for designing the Hagia Sophia), used a type of camera obscura in his experiments.[6]

The Song Dynasty Chinese scientist Shen Kuo (1031–1095) experimented with a camera obscura, and was the first to apply geometrical and quantitative attributes to it in his book of 1088 AD, the Dream Pool Essays.[7][verification needed] However, Shen Kuo alluded to the fact that the Miscellaneous Morsels from Youyang written in about 840 AD by Duan Chengshi (d. 863) during the Tang Dynasty (618–907) mentioned inverting the image of a Chinese pagoda tower beside a seashore.[7] In fact, Shen makes no assertion that he was the first to experiment with such a device.[7] Shen wrote of Cheng's book: "[Miscellaneous Morsels from Youyang] said that the image of the pagoda is inverted because it is beside the sea, and that the sea has that effect. This is nonsense. It is a normal principle that the image is inverted after passing through the small hole."[7]

In 13th-century England Roger Bacon described the use of a camera obscura for the safe observation of solar eclipses.[8] Its potential as a drawing aid may have been familiar to artists by as early as the 15th century; Leonardo da Vinci (1452–1519 AD) described camera obscura in Codex Atlanticus. Johann Zahn's Oculus Artificialis Teledioptricus Sive Telescopium was published in 1685. This work contains many descriptions and diagrams, illustrations and sketches of both the camera obscura and of the magic lantern.

Camera obscura, from a manuscript of military designs. Seventeenth century, possibly Italian.

The Dutch Masters, such as Johannes Vermeer, who were hired as painters in the 17th century, were known for their magnificent attention to detail. It has been widely speculated that they made use of such a camera, but the extent of their use by artists at this period remains a matter of considerable controversy, recently revived by the Hockney-Falco thesis. The term "camera obscura" was first used by the German astronomer Johannes Kepler in 1604.[9] The English physician and author Sir Thomas Browne speculated upon the inter-related workings of optics and the camera obscura in his 1658 Discourse The Garden of Cyrus thus-

For at the eye the Pyramidal rayes from the object, receive a decussation, and so strike a second base upon the Retina or hinder coat, the proper organ of Vision; wherein the pictures from objects are represented, answerable to the paper, or wall in the dark chamber; after the decussation of the rayes at the hole of the hornycoat, and their refraction upon the Christalline humour, answering the foramen of the window, and the convex or burning-glasses, which refract the rayes that enter it.

4 drawings by Canaletto, representing Campo San Giovanni e Paolo in Venice, obtained with a Camera obscura. (Venice, Gallerie dell'Accademia)

Early models were large; comprising either a whole darkened room or a tent (as employed by Johannes Kepler). By the 18th century, following developments by Robert Boyle and Robert Hooke, more easily portable models became available. These were extensively used by amateur artists while on their travels, but they were also employed by professionals, including Paul Sandby, Canaletto and Joshua Reynolds, whose camera (disguised as a book) is now in the Science Museum (London). Such cameras were later adapted by Joseph Nicephore Niepce, Louis Daguerre and William Fox Talbot for creating the first photographs.

Gallery

See also

Notes

  1. ^ Needham, Joseph. (1986). Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 1, Physics. Taipei: Caves Books Ltd. Page 82.
  2. ^ Ouellette, Jennifer. (2005). Black Bodies and Quantum Cats: Tales from the Annals of Physics. London: Penguin Books Ltd. Page 52.
  3. ^ Aristotle, Problems, Book XV
  4. ^ Jan Campbell (2005). "Film and cinema spectatorship: melodrama and mimesis". Polity. p.114. ISBN 074562930X
  5. ^ The Camera Obscura : Aristotle to Zahn
  6. ^ Crombie, Alistair Cameron (1990), Science, optics, and music in medieval and early modern thought, Continuum International Publishing Group, pp. 205, ISBN 9780907628798, http://books.google.com/books?id=zWrH7h9jNgUC, retrieved 22 August 2010 
  7. ^ a b c d Needham, Volume 4, Part 1, 98.
  8. ^ BBC - The Camera Obscura
  9. ^ History of Photography and the Camera - Part 1: The first photographs

References

  • Hill, Donald R. (1993), "Islamic Science and Engineering", Edinburgh University Press, page 70.
  • Lindberg, D.C. (1976), "Theories of Vision from Al Kindi to Kepler", The University of Chicago Press, Chicago and London.
  • Nazeef, Mustapha (1940), "Ibn Al-Haitham As a Naturalist Scientist", (Arabic), published proceedings of the Memorial Gathering of Al-Hacan Ibn Al-Haitham, 21 December 1939, Egypt Printing.
  • Needham, Joseph (1986). Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 1, Physics. Taipei: Caves Books Ltd.
  • Omar, S.B. (1977). "Ibn al-Haitham's Optics", Bibliotheca Islamica, Chicago.
  • Wade, Nicholas J.; Finger, Stanley (2001), "The eye as an optical instrument: from camera obscura to Helmholtz's perspective", Perception 30 (10): 1157–1177, doi:10.1068/p3210, PMID 11721819 

External links


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Camera Obscura — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. Camera obscura est le nom latin de l instrument d optique appelé chambre noire en français. Le nom peut également désigner : Camera obscura, un… …   Wikipédia en Français

  • Camera Obscura — Saltar a navegación, búsqueda Este artículo trata sobre el grupo musical escocés. Para el instrumento óptico vea Cámara oscura. Camera Obscura Información personal …   Wikipedia Español

  • Camĕra obscura — (lat., »finstere Kammer«), eine von Erasmus Reinhold in Wittenberg 1540 zur Beobachtung einer Sonnenfinsternis erfundene optische Vorrichtung, besteht aus einem dunkeln Raum, in den die von den äußern Gegenständen ausgehenden Lichtstrahlen durch… …   Meyers Großes Konversations-Lexikon

  • Camera obscura — Camera obscura, optische Kammer, Dunkelkammer, eine von Leonardo da Vinci [1] (1500) erfundene, von Erasmus Reinhold (1540) und besonders von Giambattista della Porta (1553) vervollkommnete Vorrichtung zur Projektion reeller Bilder von… …   Lexikon der gesamten Technik

  • Camera obscura — Camera obscura. Im Bau der Camera clara ähnlich (s. d.), nur mit dem Unterschiede, daß man statt des obern großen Linsenglases ein flaches, matt geschliffenes Glas anzuwenden pflegt, auf dessen unterer Fläche sich die Bilder der Gegenstände… …   Damen Conversations Lexikon

  • Camera obscura — Cam e*ra ob*scu ra [LL. camera chamber + L. obscurus, obscura, dark.] (Opt.) 1. An apparatus in which the images of external objects, formed by a convex lens or a concave mirror, are thrown on a paper or other white surface placed in the focus of …   The Collaborative International Dictionary of English

  • Camĕra obscura — (lat., d.i. Finstere Kammer), Vorkehrung, durch welche sich äußere Gesichtsgegenstände in einem dunkeln Raum auf einer bestimmten Fläche farbig darstellen. a) Die Einfache (Optische) C. o. wird erhalten, indem man in einem ganz. verfinsterten… …   Pierer's Universal-Lexikon

  • Camera obscura — Camĕra obscūra (lat.), Vorrichtung, in einem dunkeln Zimmer vermittelst des durch eine feine Öffnung im Fensterladen eindringenden Lichtes ein (verkehrtes) Bild der äußern Gegenstände auf der Gegenwand entstehen zu lassen [Abb. 311],… …   Kleines Konversations-Lexikon

  • camera obscura — 1725, a darkened room; c.1730, a device for project pictures; see CAMERA (Cf. camera) …   Etymology dictionary

  • camera obscura — [əb skyoor′ə] n. [ModL, lit., dark chamber < L: see CAMERA & OBSCURE] a dark chamber with a lens or opening through which an image is projected in natural colors onto an opposite surface …   English World dictionary

  • Camera obscura — (dunkle Kammer), ein optisches Instrument, durch welches sich die Bilder von Gegenständen in ihrer natürlichen Farbe darstellen. Die einfachste C. o. besteht in einer sehr engen Oeffnung, durch welche das Licht von außen und damit das Bild eines… …   Herders Conversations-Lexikon


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.