For other uses, see Photograph (disambiguation). This article contains instructions, advice, or how-to content. The purpose of Wikipedia is to present facts, not to train. Please help improve this article either by rewriting the how-to content or by moving it to Wikiversity or Wikibooks. (October 2010) For policy on Wikipedia, see Wikipedia:Images. Earliest known surviving heliographic engraving in existence, made by Nicéphore Niépce in 1825 by the heliography process. The image is of a 17th century Flemish engraving showing a man leading a horse. View from the Window at Le Gras (1826), Nicéphore Niépce. Generally considered the first surviving stabilized photograph of a scene from nature taken with a camera obscura. A photograph (often shortened to photo) is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic imager such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating photographs is called photography. The word "photograph" was coined in 1839 by Sir John Herschel and is based on the Greek φῶς (phos) "light" and γραφή (graphê) "representation by means of lines" or "drawing", together meaning "drawing with light".1 Contents 1 History 2 Types of photographs 3 Preservation 3.1 Paper folders 3.2 Polyester enclosures 3.3 Handling and care 4 Myths and beliefs 5 Legal issues 6 See also 7 References History Main article: History of photography The first permanent photograph was made in 18222 by a French inventor, Joseph Nicéphore Niépce, building on a discovery by Johann Heinrich Schultz (1724): that a silver and chalk mixture darkens under exposure to light. Niépce and Louis Daguerre refined this process. Daguerre discovered that exposing the silver first to iodine vapor, before exposure to light, and then to mercury fumes after the photograph was taken, could form a latent image; bathing the plate in a salt bath then fixes the image. These ideas led to the famous daguerreotype.

The daguerreotype had its problems, notably the fragility of the resulting picture, and that it was a positive-only process and thus could not be re-printed. Inventors set about looking for improved processes that would be more practical. Several processes were introduced and used for a short time between Niépce's first image and the introduction of the collodion process in 1848. Collodion-based wet-glass plate negatives with prints made on albumen paper remained the preferred photographic method for some time, even after the introduction of the even more practical gelatin process in 1871. Adaptations of the gelatin process have remained the primary black-and-white photographic process to this day, differing primarily in the film material itself, originally glass and then a variety of flexible films. Color photography is almost as old as black-and-white, with early experiments dating to John Herschel's experiments with Anthotype from 1842, and Lippmann plate from 1891. Color photography became much more popular with the introduction of Autochrome Lumière in 1903, which was replaced by Kodachrome, Ilfochrome and similar processes. For many years these processes were used almost exclusively for transparencies (in slide projectors and similar devices), but color prints became popular with the introduction of the Chromogenic negative, which is the most-used system in the C-41 process. The needs of the movie industry have also introduced a host of special-purpose systems, perhaps the best-known being the now rare Technicolor. Types of photographs Non-digital photographs are produced with a two-step chemical process. In the two-step process the light-sensitive film captures a negative image (colors and lights/darks are inverted). To produce a positive image, the negative is most commonly transferred ('printed') onto photographic paper. Printing the negative onto transparent film stock is used to manufacture motion picture films.

Alternatively, the film is processed to invert the negative image, yielding positive transparencies. Such positive images are usually mounted in frames, called slides. Before recent advances in digital photography, transparencies were widely used by professionals because of their sharpness and accuracy of color rendition. Most photographs published in magazines were taken on color transparency film. Originally all photographs were monochromatic, or hand-painted in color. Although methods for developing color photos were available as early as 1861, they did not become widely available until the 1940s or 50s, and even so, until the 1960s most photographs were taken in black and white. Since then, Color photography has dominated popular photography, although black and white is still used, being easier to develop than color. Panoramic format images can be taken with cameras like the Hasselblad Xpan on standard film. Since the 1990s, panoramic photos have been available on the Advanced Photo System film. APS was developed by several of the major film manufacturers to provide a film with different formats and computerized options available, though APS panoramas were created using a mask in panorama-capable cameras, far less desirable than a true panoramic camera, which achieves its effect through a wider film format. APS has become less popular and is being discontinued. The advent of the microcomputer and digital photography has led to the rise of digital prints. These prints are created from stored graphic formats such as JPEG, TIFF, and RAW. The types of printers used include inkjet printers, dye-sublimation printer, laser printers, and thermal printers. Inkjet prints are sometimes given the coined name "Giclée". The web has been a popular medium for storing and sharing photos ever since the first photograph was published on the web by Tim Berners-Lee in 1992 (an image of the CERN house band Les Horribles Cernettes). Today popular sites such as Flickr, Picasa and PhotoBucket are used by millions of people to share their pictures. Preservation Paper folders

Ideal photograph storage involves placing each photo in an individual folder constructed from buffered, or acid-free paper.3 Buffered paper folders are especially recommended in cases when a photograph was previously mounted onto poor quality material or using an adhesive that will lead to even more acid creation.4 Store photographs measuring 8x10 inches or smaller vertically along the longer edge of the photo in the buffered paper folder, within a larger archival box, and label each folder with relevant information to identify it. The rigid nature of the folder protects the photo from slumping or creasing, as long as the box is not packed too tightly or under filled. Folder larger photos or brittle photos stacked flat within archival boxes with other materials of comparable size.5 Polyester enclosures The most stable of plastics used in photo preservation, polyester, does not generate any harmful chemical elements, but nor does it have any capability to absorb acids generated by the photograph itself. Polyester sleeves and encapsulation have been praised for their ability to protect the photograph from humidity and environmental pollution, slowing the reaction between the item and the atmosphere. This is true, however the polyester just as frequently traps these elements next to the material it is intended to protect. This is especially risky in a storage environment that experiences drastic fluctuations in humidity or temperature, leading to ferrotyping, or sticking of the photograph to the plastic.6 Photographs sleeved or encapsulated in polyester cannot be stored vertically in boxes because they will slide down next to each other within the box, bending and folding, nor can the archivist write directly onto the polyester to identify the photograph. Therefore, it is necessary to either stack polyester protected photographs horizontally within a box, or bind them in a three ring binder. Stacking the photos horizontally within a flat box will greatly reduce ease of access, and binders leave three sides of the photo exposed to the effects of light7 and do not support the photograph evenly on both sides, leading to slumping and bending within the binder. The plastic used for enclosures has been manufactured to be as frictionless as possible to prevent scratching photos during insertion to the sleeves. Unfortunately, the slippery nature of the enclosure generates a build-up of static electricity, which attracts dust and lint particles. The static can attract the dust to the inside of the sleeve, as well, where it can scratch the photograph.8 Likewise, these components that aid in insertion of the photo, referred to as slip agents, can break down and transfer from the plastic to the photograph, where they deposit as an oily film, attracting further lint and dust. At this time, there is no test to evaluate the long-term effects of these components on photographs. In addition, the plastic sleeves can develop kinks or creases in the surface, which will scratch away at the emulsion during handling.9 Handling and care

It is best to leave photographs lying flat on the table when viewing them. Do not pick it up from a corner, or even from two sides and hold it at eye level. Every time the photograph bends, even a little, this can break down the emulsion.10 The very nature of enclosing a photograph in plastic encourages users to pick it up; users tend to handle plastic enclosed photographs less gently than non-enclosed photographs, simply because they feel the plastic enclosure makes the photo impervious to all mishandling. As long as a photo is in its folder, there is no need to touch it; simply remove the folder from the box, lay it flat on the table, and open the folder. If for some reason the researcher or archivist does need to handle the actual photo, perhaps to examine the verso for writing, he or she can use gloves if there appears to be a risk from oils or dirt on the hands. Myths and beliefs Since daguerreotypes were rendered on a mirrored surface, many spiritualists also became practitioners of the new art form. Spiritualists would claim that the human image on the mirrored surface was akin to looking into one's soul. The spiritualists also believed that it would open their souls and let demons in. Aborigines believed that taking one's picture took part of one's soul away.citation needed See also aniconism. Legal issues Laws on child pornography, extreme pornography, etc. often restrict photographs and films even more than the depicted acts: photographs and films of legal acts may be illegal. See also Wikimedia Commons has media related to: Photographs Look up photograph in Wiktionary, the free dictionary. Archival science Digital photography Largest photographs in the world Photo slideshow Photograph stability Photographic printing Pseudo-photograph Director of Photography View from the Window at Le Gras Hand-colouring of photographs References ^ Online Etymology Dictionary ^ "The First Photograph - Heliography". http://www.hrc.utexas.edu/exhibitions/permanent/wfp/heliography.html. Retrieved 2009-09-29. "from Helmut Gernsheim's article, "The 150th Anniversary of Photography," in History of Photography, Vol. I, No. 1, January 1977: ... In 1822, Niépce coated a glass plate ... The sunlight passing through ... This first permanent example ... was destroyed ... some years later."  ^ Albright, Gary. “Storage Enclosures for Photographic Materials.” Northeast Document Conservation Center. 2007. 9 February 2008. NEDCC.org. ^ Norris, Debbie Hess. “Caring for Your Photographic Collections.” Library of Congress. Feb. 9 2008, LOC.gov ^ “How Should I Store my Photographic Prints?” Preservation and Archives Professionals. The National Archives and Records Administration. 9 February 2008, Archives.gov ^ Albright, Gary. “Storage Enclosures for Photographic Materials.” Northeast Document Conservation Center. 2007. 9 February 2008. NEDCC.org. ^ International Organization for Standardization. ISO 18902:2001(E). Geneva, Switzerland: ISO Office, 2007. ^ Albright, Gary. “Storage Enclosures for Photographic Materials.” Northeast Document Conservation Center. 2007. 9 February 2008, NEDCC.org. ^ International Organization for Standardization. ISO 18902:2001(E). Geneva, Switzerland: ISO Office, 2007. ^ Baggett, James L. “Handle with Care: Photos.” Alabama Librarian. 54.1 (2004): 5. v · d · ePhotography Technical terms Angle of view · Aperture · Chromatic Aberration · Circle of confusion · Color temperature  · Depth of field · Depth of focus · Exposure · Exposure compensation · Exposure value · F-number · Film format · Film speed · Focal length · Guide number  · Hyperfocal distance · Metering mode · Perspective distortion · Photograph · Photographic printing · Photographic processes · Reciprocity · Red-eye effect · Science of photography · Shutter speed · Sync · Zone System Genres Aerial · Black-and-white · Commercial · Cloudscape · Documentary · Erotic · Fashion · Fine art · Forensic · Glamour · High speed · Landscape · Lomography · Nature · Nude · Photojournalism · Pornography · Portrait · Post-mortem · Senior · Social documentary · Sports · Still life · Stock · Street · Vernacular · Underwater · Wedding · Wildlife Techniques Afocal photography · Bokeh · Contre-jour · Cyanotype · Fill flash · Fireworks · Harris shutter · Holography · Infrared · Kite aerial · Long exposure · Macro · Multiple exposure · Night · Panning · Panoramic · Photogram (Kirlian) · Print toning · Rephotography · Rollout · Sabatier Effect · Stereoscopy · Stopping down · Sun printing · Tilt-shift · Time-lapse · Ultraviolet · Vignetting Composition Diagonal Method · Framing · Geometry and symmetry · Headroom · Lead room · Rule of thirds · Simplicity Equipment Camera (Pinhole · Rangefinder · SLR · Still · TLR · Toy · View) · Darkroom (Enlarger · Safelight) · Film (Base · Format · Holder · Stock) · Filter · Flash (Beauty dish · Cucoloris · Gobo · Grid  · Monolight · Snoot · Softbox · Umbrella  · Wireless sync)  · Lens · Manufacturers · Movie projector · Slide projector · Tripod · Tripod head · Zone plate History Analog photography · Autochrome Lumière · Box camera · Calotype · Camera obscura · Daguerreotype · Dufaycolor · Heliography · Painted photography backdrops · Photography and the law · Timeline of photography technology · Visual arts Digital photography Digital camera (D-SLR · Comparison of D-SLRs · Digital camera back) · Digiscoping · Digital versus film photography · Film scanner · Image sensor (CMOS APS · CCD · Three-CCD camera · Foveon X3 sensor) · Photo sharing · Pixel Color photography Color · Color film (Print · Slide) · Color management (CMYK color model · Color space · Primary color · RGB color model) Photographic processing C-41 process · Cross processing · Developer · Dye coupler · E-6 process · Fixer · Gelatin silver process · Gum printing · K-14 process · Print permanence · Push processing · Stop bath List of most expensive photographs · List of photographers · Photography museums and galleries (category) · Portal · WikiProject v · d · eVisualization of technical information Fields Biological data visualization · Chemical imaging · Crime mapping · Data visualization · Educational visualization · Flow visualization · Geovisualization · Information visualization · Mathematical visualization · Medical imaging · Molecular graphics · Product visualization · Scientific visualization · Software visualization · Technical drawing · Volume visualization Image types Chart · Computer graphics · Diagram · Graph of a function · Engineering drawing · Ideogram · Information graphics · Map · Photograph · Pictogram · Plot · Statistical graphics · Table · Technical drawings · Technical illustration Experts Jacques Bertin · Stuart Card · Thomas A. DeFanti · Michael Friendly · Nigel Holmes · Alan MacEachren · Jock D. Mackinlay · Michael Maltz · Bruce H. McCormick · Charles Joseph Minard · Otto Neurath · William Playfair · Clifford A. Pickover · Arthur H. Robinson · Lawrence J. Rosenblum · Adolphe Quetelet · George G. Robertson · Ben Shneiderman · Edward Tufte Related topics Cartography · Computer graphics · Graph drawing · Graphic design · Imaging science · Information science · Mental visualisation · Neuroimaging · Scientific modelling · Spatial analysis · Visual analytics · Visual perception