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This article is about a photographic device. For other uses, see Camera obscura (disambiguation).

The camera obscura (Lat. dark chamber) was an optical device used in drawing, and one of the ancestral threads leading to the invention of photography. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Photography (fә'tɒgrәfi or fә'tɑːgrәfi (from Greek φωτο and γραφία is the process and Art of recording pictures by means of capturing In English, today's photographic devices are still known as "cameras". A camera is a device used to capture images either as still Photographs or as sequences of moving images ( Movies or Videos.

The principle of the camera obscura can be demonstrated with a rudimentary type, just a box (which may be room-sized, or even hangar sized) with a hole in one side, (see pinhole camera for construction details). A' pinhole camera' is a very simple Camera with no lens and a single very small Aperture. A' pinhole camera' is a very simple Camera with no lens and a single very small Aperture. Light from only one part of a scene will pass through the hole and strike a specific part of the back wall. The projection is made on paper on which an artist can then copy the image. The advantage of this technique is that the perspective is accurate, thus greatly increasing the realism of the image (correct perspective in drawing can also be achieved by looking through a wire mesh and copying the view onto a canvas with a corresponding grid on it). Perspective (from Latin perspicere to see through in the graphic arts such as drawing is an approximate representation on a flat surface (such as paper of an image as it is perceived

With this simple do-it-yourself apparatus, the image is always upside-down. By using mirrors, as in the 18th century overhead version (illustrated in the Discovery and Origins section below), it is also possible to project an up-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 upright as viewed from the back. Tracing paper is a type of Translucent Paper. It is made by immersing unsized and unloaded paper of good Quality in Sulfuric acid for a few

As a pinhole is made smaller, the image gets sharper, but the light-sensitivity decreases. With too small a pinhole the sharpness again becomes worse due to diffraction. Diffraction is normally taken to refer to various phenomena which occur when a wave encounters an obstacle Practical camerae obscurae use a lens rather than a pinhole because it allows a larger aperture, giving a usable brightness while maintaining focus. A lens is an optical device with perfect or approximate Axial symmetry which transmits and refracts Light, converging or diverging

A freestanding room-sized camera obscura at the University of North Carolina at Chapel Hill. One of the pinholes can be seen in the panel to the left of the door.
A freestanding room-sized camera obscura at the University of North Carolina at Chapel Hill. The University of North Carolina at Chapel Hill ( UNC, North Carolina, or simply Carolina) is a public, Coeducational Research One of the pinholes can be seen in the panel to the left of the door.

Contents

Discovery and origins

The first mention and discovery of the principles behind the pinhole camera, a precursor to the camera obscura, belong to Mo-Ti (470 BC to 390 BC), a Chinese philosopher and founder of Mohism. A' pinhole camera' is a very simple Camera with no lens and a single very small Aperture. Mozi ( Lat as Micius, ca 470 BCE&ndashca 391 BCE was a Philosopher who lived in China during the Hundred Schools of Thought China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National Mohism or Moism ( was a Chinese philosophy developed by the followers of Mozi (also referred to as Mo Di 470 &ndashc Other observations made by Mozi and his followers include Newton's first law of motion. Newton's laws of motion are three Physical laws which provide relationships between the Forces acting on a body and the motion of the The Mohist tradition is also highly unusual in Chinese thought in that it devoted time to developing principles of logic. Further down the line, Aristotle (384 to 322 BC) understood the optical principle of the pinhole camera. Aristotle (Greek Aristotélēs) (384 BC – 322 BC was a Greek philosopher a student of Plato and teacher of Alexander the Great. 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 first camera obscura was later built by an Iraqi scientist named Abu Ali Al-Hasan Ibn al-Haitham, born in Basra (965-1039 AD), known in the West as Alhacen or Alhazen, who carried out practical experiments on optics in his Book of Optics. TemplateInfobox Muslim scholars --> ( Arabic: ابو علی، حسن بن حسن بن هيثم Latinized The term Western world, the West or the Occident ( Latin: occidens -sunset -west as distinct from the Orient) can have multiple meanings The Book of Optics ( Arabic: Kitab al-Manazir, Latin: De Aspectibus or Opticae Thesaurus Alhazeni [1] In his various experiments, Ibn Al-Haitham used the term “Al-Bayt al-Muthlim”(Arabic: البيت المظلم), translated in English as dark room. Arabic (ar الْعَرَبيّة (informally ar عَرَبيْ) in terms of the number of speakers is the largest living member of the Semitic language In the experiment he undertook, in order to establish that light travels in time and with speed, he says: “If the hole was covered with a curtain and the curtain was taken off, the light traveling from the hole to the opposite wall will consume time. ” He reiterated the same experience when he established that light travels in straight lines. The most revealing experiment which indeed introduced the camera obscura was in his studies of the half-moon shape of the sun’s image during eclipses which he observed on the wall opposite a small hole made in the window shutters. In his famous essay "On the form of the Eclipse" (Maqalah-fi-Surat-al-Kosuf) (Arabic: مقالة في صورةالكسوف) he commented on his observation "The image of the sun at the time of the eclipse, unless it is total, demonstrates that when its light passes through a narrow, round hole and is cast on a plane opposite to the hole it takes on the form of a moon-sickle”. Arabic (ar الْعَرَبيّة (informally ar عَرَبيْ) in terms of the number of speakers is the largest living member of the Semitic language

In his experiment of the sun light he extended his observation of the penetration of light through the pinhole to conclude that when the sun light reaches and penetrates the hole it makes a conic shape at the points meeting at the pinhole, forming later another conic shape reverse to the first one on the opposite wall in the dark room. This happens when sun light diverges from point “ﺍ” until it reaches an aperture “ﺏﺤ” and is projected through it onto a screen at the luminous spot “ﺩﻫ”. Since the distance between the aperture and the screen is insignificant in comparison to the distance between the aperture and the sun, the divergence of sunlight after going through the aperture should be insignificant. In other words, “ﺏﺤ” should be about equal to “ﺩﻫ”. However, it is observed to be much greater “ﻙﻁ” when the paths of the rays which form the extremities of “ﻙﻁ” are retraced in the reverse direction, it is found that they meet at a point outside the aperture and then diverge again toward the sun as illustrated in figure 1. This was indeed the first accurate description of the Camera Obscura phenomenon.

Alhacen's observations of light's behaviour through a pinhole
Alhacen's observations of light's behaviour through a pinhole

In camera terms, the light converges into the room through the hole transmitting with it the object(s) facing it. The object will appear in full colour but upside down on the projecting screen/wall opposite the hole inside the dark room. The explanation is that light travels in a straight line and when some of the rays reflected from a bright subject pass through the small hole in thin material they do not scatter but cross and reform as an upside down image on a flat white surface held parallel to the hole. Ib Al-Haitham established that the smaller the hole is, the clearer the picture is.

History

Although both the pinhole camera and camera obscura is credited to Ibn al-Haytham[2], the camera obscura was first described by Aristotle, who was the first to describe how an image is formed on the eye, using the camera obscura as an analogy. A' pinhole camera' is a very simple Camera with no lens and a single very small Aperture. TemplateInfobox Muslim scholars --> ( Arabic: ابو علی، حسن بن حسن بن هيثم Latinized Aristotle (Greek Aristotélēs) (384 BC – 322 BC was a Greek philosopher a student of Plato and teacher of Alexander the Great. Alhazen states (in the Latin translation), and with respect to the camera obscura, "Et nos non inventimus ita", we did not invent this. [3] Several decades after Ibn al-Haitham's death, the Song Dynasty Chinese scientist Shen Kuo (1031-1095) experimented with camera obscura, and was the first to apply geometrical and quantitative attributes to it in his book of 1088 AD, the Dream Pool Essays. The Song Dynasty ( Wade-Giles: Sung Ch'ao was a ruling dynasty in China between 960&ndash1279 CE it succeeded the Five Dynasties and Ten Kingdoms The term Chinese people may refer to any of the following A person who resides in and holds citizenship of the People's Republic of China (including Hong Shen Kuo or Shen Kua ( (1031&ndash1095 style name Cunzhong and pseudonym Mengqi Weng, was a Polymathic Chinese Geometry ( Greek γεωμετρία; geo = earth metria = measure is a part of Mathematics concerned with questions of size shape and relative position A quantitative attribute is one that exists in a range of magnitudes and can therefore be measured. The Dream Pool Essays ( Pinyin: Meng Xi Bi Tan; Wade-Giles: Meng Ch'i Pi T'an Chinese: 夢溪筆談／梦溪笔谈 [4] 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. Leonardo di ser Piero da Vinci ( April 15 1452 – May 2 1519 was an Italian Polymath, having been a scientist Mathematician, Engineer The Codex Atlanticus is an important twelve-volume bound set of drawings and writings by Leonardo da Vinci, the largest such set its name indicates its atlas-like breadth Johann Zahn's Oculus Artificialis Teledioptricus Sive Telescopium was published in 1685. Johann Zahn (1631—1707 was the seventeenth century German author of Oculus Artificialis Teledioptricus Sive Telescopium ( Würzburg, 1685 This work contains many descriptions and diagrams, illustrations and sketches of both the camera obscura and of the magic lantern. The magic lantern or Lanterna Magica was the ancestor of the modern Slide projector.

A freestanding room-sized camera obscura in the shape of a camera located in San Francisco at the Cliff House in Ocean Beach (San Francisco)
A freestanding room-sized camera obscura in the shape of a camera located in San Francisco at the Cliff House in Ocean Beach (San Francisco)

The Dutch Masters, such as Johannes Vermeer, who were hired as painters in the 17th Century, were known for their magnificent attention to detail. The City and County of San Francisco is the fourth most populous city The Cliff House is a Restaurant perched on the headlands on the cliffs just north of Ocean Beach on the western side of San Francisco California. Ocean Beach is a Beach that runs along the west coast of San Francisco, California, United States, at the Pacific Ocean. "Dutch Masters" redirects here for the cigar see Dutch Masters (cigar. Johannes or Jan Vermeer (baptized in Delft with the name Joannis on October 31 1632, and buried in the same city under the name Jan As a means of recording the passage of Time, the 17th Century was that Century which lasted from 1601 - 1700 in the Gregorian calendar 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 Hockney-Falco thesis is a controversial theory of Art history, advanced by artist David Hockney and physicist Charles M

Early models were large; comprising either a whole darkened room or a tent (as employed by Johannes Kepler). Johannes Kepler (ˈkɛplɚ ( December 27 1571 &ndash November 15 1630) was a German Mathematician, Astronomer By the 18th century, following developments by Robert Boyle and Robert Hooke, more easily portable models became available. The 18th century lasted from 1701 to 1800 in the Gregorian calendar, in accordance with the Anno Domini / Common Era numbering system Robert Boyle was a Natural philosopher, chemist physicist inventor and early Gentleman scientist, noted for his work in Physics and Chemistry Robert Hooke, FRS (18 July 1635 – 3 March 1703 was an English Natural philosopher and Polymath who played an important role in the 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). Paul Sandby (1731 (baptised - 9 November 1809) was an English Map -maker turned landscape painter in Watercolours who This is about the first and better known artist "Canaletto" for his nephew and pupil sometimes also called "Canaletto" especially in Poland and Germany see Sir Joshua Reynolds RA FRS FRSA (16 July 1723 &ndash 23 February 1792 was the most important and influential of 18th century English painters For science museums in general check out Science museum. The Science Museum on Exhibition Road, South Kensington, London is part Such cameras were later adapted by Louis Daguerre and William Fox Talbot for creating the first photographs. William Henry Fox Talbot (11 February 1800 – 17 September 1877 was the inventor of the negative / positive photographic process the precursor to most photographic processes of

Tourist attractions

Some camera obscura have been built as tourist attractions, often taking the form of a large chamber within a high building that can be darkened so that a 'live' panorama of the world outside is projected onto a horizontal surface through a rotating lens. Although few now survive, examples can be found at the following locations:

There is also a portable example which Willett & Patteson tour around England and the world. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe.

See also

Notes

  1. ^ Nicholas J. The Hockney-Falco thesis is a controversial theory of Art history, advanced by artist David Hockney and physicist Charles M Black mirror redirects here See Black mirror (disambiguation for other uses A camera lucida is an Optical device used as a drawing aid by Artists The camera lucida performs an optical superimposition of the subject being viewed The history of film spans over a hundred years from the latter part of the 19th century to the beginning of the 21st century. The magic lantern or Lanterna Magica was the ancestor of the modern Slide projector. A camera is a device used to capture images either as still Photographs or as sequences of moving images ( Movies or Videos. Wade, Stanley Finger (2001), "The eye as an optical instrument: from camera obscura to Helmholtz's perspective", Perception 30 (10), p. 1157–1177.
  2. ^ Wade, Finger.
  3. ^ Adventures in CyberSound: The Camera Obscura
  4. ^ Needham, Volume 4, Part 1, 98.

References

External links

Dictionary

camera obscura

-noun

  1. A darkened chamber in which the image of an outside object is projected and focused onto a surface
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