The daguerreotype, introduced in 1839, was the first publicly announced photographic process and the first to come into widespread use. By the early 1860s, later processes which were less costly and produced more easily viewed images with shorter exposure times had almost entirely replaced it. A small-scale revival of daguerreotypy among photographers interested in historical processes was increasingly evident in the 1980s and 1990s and has persisted into the 2010s.
The daguerreotype image is formed on a highly polished silver surface, normally Sheffield plate. The silver surface is polished with a leather buff using first rotten stone and then jeweler's rouge and then, by the light of a safelight, exposed to iodine fumes from iodine crystals at room temperature (usually followed by similar exposure to bromine and chlorine), producing a light-sensitive silver halide coating. The plate is then carried to the camera in a light-tight plate holder. Withdrawing the protective dark slide exposes the sensitized surface to the image projected within the dark camera by the lens, creating an invisible latent image on the plate which is then developed to visibility by fuming it with heated mercury. After development, the light sensitivity of the plate is arrested by removing the remaining silver halide with a mild solution of sodium thiosulfate or a hot saturated solution of common salt. To give the image a warmer tone and physically reinforce the powder-like silver particles of which it is composed, a gold chloride solution is pooled onto the image and the plate is briefly heated over a flame, then drained, rinsed and dried. Even after this gilding treatment, the image surface is still very delicate and the silver is subject to tarnishing from exposure to the air, so the plate must be kept under glass in a sealed enclosure.
The distinguishing visual characteristics of a daguerreotype are that the image is on a bright (ignoring any areas of tarnish) mirror-like surface of metallic silver and it will appear either positive or negative depending on the lighting conditions and whether a light or dark background is being reflected in the metal.
Several types of antique images, most commonly ambrotypes and tintypes but sometimes even prints on paper, are frequently misidentified as daguerreotypes, especially if they are in the small, ornamented cases in which daguerreotypes were usually housed. The name "daguerreotype" correctly refers only to one very distinctive image type and medium, produced by a specific photographic process that was in wide use only from the early 1840s to the late 1850s.
Since the late Renaissance, artists and inventors had searched for a mechanical method of capturing visual scenes. Previously, using the camera obscura, artists would manually trace what they saw, or use the optical image in the camera as a basis for solving the problems of perspective and parallax, and deciding color values. The camera obscura's optical reduction of a real scene in three-dimensional space to a flat rendition in two dimensions influenced western art, so that at one point, it was thought that images based on optical geometry (perspective) belonged to a more advanced civilization. Later, with the advent of Modernism, the absence of perspective in oriental art from China, Japan and in Persian miniatures was revalued.
Previous discoveries of photosensitive methods and substances — including silver nitrate by Albertus Magnus in the 13th century, a silver and chalk mixture by Johann Heinrich Schulze in 1724, and Joseph Niépce's bitumen-based heliography in 1822 — contributed to development of the daguerreotype. The first reliably documented attempt to capture the image formed in a camera obscura was made by Thomas Wedgwood as early as the 1790s, but according to an 1802 account of his work camera images were "found too faint to produce, in any moderate time, an effect upon the nitrate of silver."
In 1829 French artist and chemist Louis Jacques-Mandé Daguerre, contributing a cutting edge camera design, partnered with Niépce, a leader in photochemistry, to further develop their technologies. The two men came into contact through their optician, Chevalier, who supplied lenses for their camerae obscurae.
Niépce's aim originally had been to find a method to reproduce prints and drawings for lithography. He had started out experimenting with light sensitive materials and had made a contact print from a drawing and then went on to successfully make the first photomechanical record of an image in a camera obscura—the world's first photograph. Niépce's method was to coat a metal plate with bitumen of Judea (asphalt) and the action of the light differentially hardened the bitumen. The plate was washed with oil of lavender leaving a relief image. Niépce called his process heliography and the exposure for the first successful photograph was eight hours.
After Niépce's 1833 death, Daguerre continued to research the chemistry and mechanics of recording images by coating copper plates with iodized silver. Early experiments required hours of exposure in the camera to produce visible results. In 1835 Daguerre discovered—after accidentally breaking a mercury thermometer, according to traditional accounts—a method of developing the faint or invisible images on plates that had been exposed for only 20 to 30 minutes. Further refinement of his process would allow him to fix the image—preventing further darkening of the silver—using a strong solution of common salt. An 1837 still life of plaster casts, a wicker-covered bottle, a framed drawing and a curtain—titled L'Atelier de l'artiste—has been claimed to be the first daguerreotype to successfully undergo the full process of exposure, development and fixation.
The French Academy of Sciences announced the daguerreotype process on January 9, 1839. Later that year William Fox Talbot announced his silver chloride "sensitive paper" process. Together, these announcements mark 1839 as the year photography was born.
Daguerre did not patent and profit from his invention in the usual way. Instead, it was arranged that the French government would acquire the rights in exchange for a lifetime pension. The government would then present the daguerreotype process "free to the world" as a gift, which it did on August 19, 1839. However, on August 14, 1839, a patent agent acting on Daguerre's behalf filed for a patent in England. Consequently, Britain became the only nation in which the purchase of a license was legally required to make and sell daguerreotypes.
Françoise Arago noted that early attempts at photography, which required very long exposures, could not capture detail properly because of the movement of the sun, so that shadows came from different directions during the course of these long exposures.
The camera obscura is a naturally occurring phenomenon. When a hole in the wall of a dark room faces onto a brightly lit scene—for example a dark cave on the edge of a sunlit valley—a picture of the scene outside can be projected upside-down onto a sheet of paper or parchment held at a suitable distance from the hole inside the dark room. Early camerae obscurae were large dark rooms of this type (camera obscura is Latin for dark chamber). The system gives a brighter picture when the hole is replaced by a lens and portable camerae obscurae were built with an internal mirror at 45 degrees to make the image upright. They are fitted with a ground glass viewing screen and are used as a drawing aid by artists.
Daguerre would have been familiar with the camera obscura as a tool in his work as a theatrical scene painter and had developed a visual public entertainment called the Diorama. By painting on both sides of a piece of white cloth and illuminating the painting first from the front, then from the back, an illusion of movement could be obtained to depict a train crash, or the erupting of a volcano. Dioramas were opened in towns in several countries.
Copies and reproductions by lithography
Although daguerreotypes are unique images, they could be copied by re-daguerreotyping the original. Copies were also produced by lithography or engraving. Today, they can be digitally scanned.
Beginnings of the age of photomechanical reproduction
Seen from the perspective of today, when developments in photography have been to increase image quality while reducing the skill and knowledge required by the camera operator, daguerreotypes are expensive and time consuming to produce. They are cumbersome and heavy if many images are to be stored in large quantities and they require a skilled operator. Long exposures that necessitated headrests resulted in a proliferation of stiff, rigid poses in most of the surviving daguerreotypes, with some notable exceptions.
However, when the process was introduced, it offered advantages over existing technologies. Illustrations in magazines up to then had been made by woodcuts or by etching or engraving on copper plates, by mezzotint or by lithography. Portraits were made by amateur and professional artists, but capturing a likeness was revolutionized with the advent of photography.
As an astronomical application in the 1870s
Commercial portraiture was only one aspect of the opening up of the age of mechanical reproduction. Arago had in his address to the House of Deputies outlined a wealth of possible applications including astronomy and the daguerreotype was used as the cutting edge technique in astronomical photography in the 1870s. Although the collodion wet plate process offered a cheaper and more convenient alternative for commercial portraiture and for other applications with shorter exposure times, when the transit of Venus was about to occur and observations were to be made from several sites on the earth's surface in order to calculate astronomical distances, daguerreotypy proved a more accurate method of making visual recordings through telescopes because it was a dry process with greater dimensional stability, whereas collodion glass plates were exposed wet and the image would move as the plate dried.
The invention of photography (photography and daguerreotypy were one and the same) made cataclysmic changes throughout society regarding what was illusion and what was reality. It is particularly significant that the first process to emerge and to be practiced widely was able to faithfully record fine detail at a resolution that most of today's digital cameras are not able to match (when compared with a well exposed and sharp large format daguerreotype). The process is unsurpassed for reproducing fine detail over a long tonal range and gives an illusion of reality unlike any other process.
The raw material for daguerreotype plates was called Sheffield plate, plating by fusion or cold-rolled cladding and was a standard hardware item produced by heating and rolling silver foil in contact with a copper support. Today, the silver surface is produced by electroplating.
The surface of a daguerreotype is like a mirror, with the image made directly on the silver surface. It is very fragile and can be rubbed off with a finger. The finished plate also must be angled so as to reflect some dark surface for the image to be visible. Depending on the angle viewed and the color of the surface reflected into it, the image can change from a positive to a negative. The viewer's own reflection will be seen at the same time.
The fragility of the image is a disadvantage because the daguerreotypist needs to buy in a stock of glass cassettes to house the daguerreotypes produced for clients but as the astronomer Arago pointed out in his presentation of the process to the French house of Deputies, the expense of the silver is offset by being able to wipe a plate clean and produce images again and again on the same plate.
When a daguerreotype is viewed, unless it is taken through a mirror, or through a prism with a silvered hypotenuse, the image will be back to front - writing will appear as if it is being read from the back. While glass lantern plates in black and white and coloured transparencies can always be flipped over, the daguerreotype is opaque so the image photographed can only be viewed from the side of the plate facing the lens.
Copying or lithographing a daguerreotype will revert the image so that writing reads correctly. A prism with a silvered hypotenuse was designed to which reverted the image to the right way round, or a mirror could be used, but these could move in a high wind blurring the image and so photographers usually made do with mirror reversed images that were sharp.
The very first daguerreotypes were kept wrapped in paper but as the image tended to rub off a method was devised of framing the finished plates with a protective glass cover. To prevent tarnishing, the air inside the glass cover is replaced by an inert gas, such as nitrogen or argon.
Because of the fragility of the image and the need to mount the daguerreotype in a protective housing, daguerreotypes are artifacts comprising the silvered plate as well as its protective housing.
There were two methods of finishing daguerreotypes for protection and display:
In the US and in Britain, the tradition of preserving miniature paintings in a wooden case covered with leather or with paper stamped with a relief pattern continued through to the daguerreotype. Some daguerreotypists were portrait artists who also offered miniature portraits. The Union case was made from a mixture of coloured sawdust and shellac (the main component of wood varnish) formed in a die heated to produce a decorative sculptural relief. The term "Union" referred to the sawdust and varnish mixture. The manufacture of these cases started in 1856; the cover was lined with red velvet or plush or satin to provide a dark surface to reflect into the plate for viewing and to protect the cover glass. Some cases held two daguerreotypes.
The other method, common in France and on continental Europe, was to hang the daguerreotype on the wall in a frame - simple or elaborate - using a passepartout. Conservators were able to determine that a daguerreotype of Walt Whitman was made in New Orleans with the main clue being the type of frame, which was made for wall hanging like the French and continental style. Supporting evidence of the New Orleans origin was a scrap of paper used to glue the plate into the frame cut from a New Orleans bilingual newspaper of the time Le Mesager Other clues to identify daguerreotypes used by historians are hallmarks in the silver plate and even the individual patterns left by different photographers when polishing the plate with a leather buff which leaves parallel lines discernible in the image.
As the daguerreotype itself is made on silver plated copper, it was suited to mounting into lockets as was done with miniature paintings. Other imaginative uses of daguerreotype portraits were to mount them into fob watches, jewelled caskets, or ornate siver boxes and jewelry.
The toxicity of the chemicals used in the daguerreotype process was well known in the 19th century, but precautionary measures were rarely taken. Today, however, the hazards of contact with mercury and iodine are taken more seriously, as well as the risk of release of chemicals into the environment.
The Becquerel process avoids mercury altogether, but requires longer exposures.
At the time the process was introduced, daguerreotyping a brightly sunlit subject typically required about ten minutes of exposure, so the earliest daguerreotypes were of still lifes and landscapes. The oldest well-documented daguerreotype featuring human subjects is Daguerre's own 1838 view of the Boulevard du Temple, a busy street in Paris. The street appears deserted because the traffic (which would have been horse-drawn carriages) was moving and left no image; but a man having his shoes shined and the bootblack, are visible because they stayed in position long enough for their images to be recorded.
Reduction of exposure time
The very first daguerreotypes used Chevalier lenses that were "slow", and the light sensitive material was silver iodide made by fuming the silver plate with iodine vapor. This meant that the exposure in the camera was too long to conveniently take portraits commercially and so the first subjects taken were immobile subjects such as street scenes, still life architectural studies, etc.
Two changes were introduced that shortened the exposure times: one was fitting lenses of a larger diameter to the camera and the other was a modification to the chemistry used.
When Petzval lenses were introduced in 1841, with a larger effective aperture and the plate was sensitized not only with iodine but also with bromine and chlorine and forming light sensitive crystals of silver iodide, silver bromide and/or silver chloride that are more light-sensitive than silver iodide alone, the exposures were reduced (the lens remaining uncapped for a shorter time), making commercial portraits viable. Increased speed was achieved using the same chemistry in the later silver processes that followed. Usually, it was arranged so that the sitters leaned their elbows on a support such as a posing table whose height could be adjusted or else head rests were used that did not show in the picture and this led to most daguerreotype portraits having stiff, lifeless poses. Some exceptions exist with lively expressions full of character as photographers saw the potential of the new medium. These are represented in museum collections and are the most sought after by private collectors today. Daguerreotypes were mounted in cases under glass with a cover, or in a frame that could be hung on a wall. They were usually sealed with tape to reduce oxidization and tarnishing of the plate as well as mechanical damage from being touched.
The process was developed by Louis Daguerre together with Joseph Nicéphore Niépce. Niépce had produced the first photographic image in the camera obscura with an eight-hour exposure using bitumen of Judea on a pewter plate developing it in lavender oil, a process he called heliography. The bitumen hardened where light had affected it, while the non-exposed portions were washed away.
The image in a daguerreotype is often described as being formed by the amalgam, or alloy, of mercury and silver because mercury vapor from a pool of heated mercury is used to develop the plate; but using the Becquerel process (using a red filter and two-and-a-half stops extra exposure) daguerreotypes can be produced without mercury, and chemical analysis shows that there is no mercury in the final image with the Becquerel process. This brings into question the theory that the image is formed of amalgam with mercury development.
Exposure times were reduced by sensitizing the plate with bromine and chlorine in addition to iodine, and by replacing the original Chevalier lens, which was best for photographing landscapes, with the larger-diameter "fast" portrait lens designed by Joseph Petzval. Voigtländer's small, all-metal Daguerrotype camera made possible an exposure time of as little as two seconds in bright sunlight, if the shadows were underexposed, but his unusual design did not catch on and was not a commercial success.
Although the daguerreotype process could only produce a single image at a time, copies could be created by re-daguerreotyping the original, although this proved difficult according to Joseph Maria Eder. says that copying daguerreotypes in the camera was difficult, but good copies are to be found. As with any original photograph that is copied, the contrast increases. With a daguerreotype, any writing will appear back to front. Recopying a daguerreotype will make the writing appear normal and rings worn on the fingers will appear on the correct hand etc. Another device to make a daguerreotype the right way round would be to use a mirror when taking the photograph.
André-Adolphe-Eugène Disdéri and Jules Itier in France, and Johann Baptist Isenring in Switzerland, became prominent daguerreotypists. In Britain, however, Richard Beard bought the British daguerreotype patent from Miles Berry in 1841 and closely controlled his investment, selling licenses throughout the country and prosecuting infringers. Among others, Antoine Claudet and Thomas Richard Williams produced daguerreotypes in the UK.
Daguerreotype photography spread rapidly across the United States. In the early 1840s, the invention was introduced in a period of months to practitioners in the United States by Samuel Morse, inventor of the telegraph code. By 1853 an estimated three million daguerreotypes per year were being produced in the United States alone. One of these original Morse Daguerreotype cameras is currently on display at the National Museum of American History, a branch of the Smithsonian Institution, in Washington, DC. A flourishing market in portraiture sprang up, predominantly the work of itinerant practitioners who traveled from town to town. For the first time in history, people could obtain an exact likeness of themselves or their loved ones for a modest cost, making portrait photographs extremely popular with those of modest means. Celebrities and everyday people sought portraits and workers would save an entire day's income to have a daguerreotype taken of them, including occupational portraits. Notable U.S. daguerreotypists of the mid-19th century included James Presley Ball, Samuel Bemis, Abraham Bogardus, Mathew Brady, Thomas Martin Easterly, François Fleischbein, Jeremiah Gurney, John Plumbe, Jr., Albert Southworth, Augustus Washington, Ezra Greenleaf Weld, and John Adams Whipple.
This method spread to other parts of the world as well. The first daguerreotype in Australia was taken in 1841, but no longer survives. The oldest surviving Australian daguerreotype is a portrait of Dr. William Bland taken in 1845. In 1857, Ichiki Shirō created the first known Japanese photograph, a portrait of his daimyo Shimazu Nariakira. This photograph was designated an Important Cultural Property by the government of Japan.
Although the daguerreotype process is usually said to have died out completely in the early 1860s, documentary evidence indicates that some very slight use of it persisted more or less continuously throughout the following 150 years of its supposed extinction. A few first-generation daguerreotypists refused to entirely abandon their beautiful old medium when they started making the new, cheaper, easier to view but comparatively drab ambrotypes and tintypes. Historically-minded photographers of subsequent generations, often fascinated by daguerreotypes, sometimes experimented with making their own or even revived the process commercially as a "retro" portraiture option for their clients. These eccentric late uses were extremely unusual and surviving examples reliably dated to between the 1860s and the 1960s are now exceedingly rare.
The daguerreotype experienced a minor renaissance in the late 20th century and the process is currently practiced by a handful of enthusiastic devotees; there are thought to be fewer than 100 worldwide (see list of artists on cdags.org in links below). In recent years artists like Jerry Spagnoli, Adam Fuss, Patrick Bailly-Maître-Grand and Chuck Close have reintroduced the medium to the broader art world. The use of electronic flash in modern daguerreotypy has solved many of the problems connected with the slow speed of the process when using daylight.
International group exhibitions of contemporary daguerreotypists' works have been held, notably the 2009 exhibition in Bry Sur Marne, France, with 182 daguerreotypes by 44 artists, and the 2013 ImageObject exhibition in New York City, showcasing 75 works by 33 artists. The appeal of the medium lies in the "magic mirror" effect of light striking the polished silver plate and revealing a silvery image which can seem ghostly and ethereal even while being perfectly sharp, and in the dedication and handcrafting required to make a daguerreotype.