Sunday, November 13, 2016

CRIMINALISTICS:Forensic Photography

Photography 
In a general sense, photography can be defined as an art, science and practice of creating images through the action of light. 

Note: 
The word photography was derived from the Greek word "phos" - light and "graphe" - drawing with light.


Evolution of Photography: 

Chinese philosopher Mo Di (Ancient Han from the Mohist School of Logic)
 The first to discover and develop the scientific principles of opticscamera obscura and pinhole camera

Later Greek mathematicians Aristotle and Euclid also independently described a pinhole camera in the 5th and 4th centuries BCE. 

Also, Byzantine mathematician Anthemius of Tralles (6th century CE) used a type of camera obscura in his experiments. 

Both the Han Chinese polymath Shen Kuo (1031–95) and Arab physicist Ibn al-Haytham (Alhazen) (965–1040) independently invented the camera obscura and pinhole camera.

Albertus Magnus (1193–1280) discovered silver nitrate

Georg Fabricius (1516–71) discovered silver chloride.

Shen Kuo explains the science of camera obscura and optical physics in his scientific work Dream Pool Essays.
Daniele Barbaro (1566) described a diaphragm.

Wilhelm Homberg (1694) described how light darkened some chemicals (photochemical effect).

The discovery of the camera obscura that provides an image of a scene dates back to ancient ChinaLeonardo da Vinci mentions natural camera obscura that are formed by dark caves on the edge of a sunlit valley. A hole in the cave wall will act as a pinhole camera and project a laterally reversed, upside down image on a piece of paper. 
The camera obscura literally means "dark chamber" in Latin. It is a box with a hole in it which allows light to go through and create an image onto the piece of paper.


Alhazen (Ibn Al-Haytham) 
Known authority on optics in the Middle ages who lived around 1000 AD, invented the first pinhole camera, (also called the Camera Obscura } and was able to explain why the images were upside down.

Angelo Sala 
A self educated chemist, he discovered that when paper contained powdered silver nitrate it would react with sunlight, causing it to darken. These pioneering experiments with silver salts were a crucial step towards the later invention of photography. He published his findings in a pamphlet in 1614.

Anna Atkins (1799- 1871) 
An English Botanist, she is considered to be the first female photographer.

Aristotle 
Observed and noted the first casual reference to the optic laws that made pinhole cameras possible, around 330 BC, he questioned why the sun could make a circular image when it shined
through a square hole.

Arthur Fellig (Weegee) 
He became famous because of his frequent, seemingly prescient arrivals at scenes only minutes after crimes, fires or other emergencies were reported to authorities.

Carl William Scheele (1742-1786) 

A Swedish scientist, self-educated. He used to work as an assistant in pharmacies and showed a talent in chemistry from a very young age. In spite an offer made to him to study in London or Berlin, he operated a pharmacy in Kφping where he spend the rest of his life and made all his important inventions. He was especially interest on chemical analysis and worked particularly
with the chemical reactions between silver nitrate and sunlight, therefore making a break through in the chemistry of photography. The records from his experiments were of a great importance for the next generations of scientists.


Frederick Scoff Archer 
An English sculptor who invented the wet plate negative in 1851. Using a viscous solution of collodion, he coated glass with light-sensitive silver salts. Because it was glass and not paper, this wet plate created a more stable and detailed negative.

George Eastman 
He invented in 1889 a film with a base that was flexible, unbreakable, and could be rolled. Emulsions coated on a cellulose nitrate film base, such as Eastman's, made the mass-produced
box camera a reality.

Hamilton Smith 

He patented in 1856 the Tintypes, another medium that heralded the birth of photography. A thin sheet of iron was used to provide a base for light-sensitive material, yielding a positive image.

      Tintypes - are a variation of the collodion wet plate process.
      The emulsion is painted onto a japanned (varnished) iron plate,
      which is exposed in the camera.

Heliographs - (sun prints) were the prototype for the modern photograph.

Henry Fox Talbot 

The English botanist and mathematician and The inventor of the first negative from which multiple positive prints were made.

Hercules Florence (1804-1879) 

In 1824 goes to Brazil and takes part in a scientific mission at the Amazon, where he becomes preoccupied with the idea of recording images from his trip. From 1830 devotes himself to research and experimentation for photography. The above, gives Brazil the ability
to claim that is one of the places in the world, where photography was found.

Hippolyte Bayard (1807-1887) 

The most unfortunate from the pioneers of photography. Discovered one direct positive photographic method. He was the first person to hold a photographic exhibition (for humanitarian reasons) and the first who combined two negatives to created one print (called Combination Printing). As a civil servant and with five hundred franks that received as financial help from
Arago for improving his method, prevented him from presenting the discovery of photography at the French Academy of Sciences.


Johann Heinrich Schulze (1687 - 1744) 
He was a German professor at the University of Altdorf. He was the first person to produce
Photograms, which were created by using paper masks in direct contact with a jar containing a mixture of silver nitrate powder and chalk. Schulze proved that the darkening of silver nitrate was caused by light and ruled out the possibility of the change being caused by temperature,
by observing no tonal change to silver nitrate when heated in an oven.

Joseph Nicephore Niepce 

He made the first photographic image with a camera obscura.

Sir Humphry Davy (1778-1829) 

Chemistry genius, friend and assistant of Wedgwood in his experiments whose results were published at Royal Society, in 1802 by Davy. The problem of "fixing" the images remained
in spite of Davy's breakthroughs in chemistry.

Sir John F.W. Hersche

A scientist who first used the word photography in 1839. The word photography was derived from the Greek words Photos, which means light and Graphein, which means to draw.

Thomas Wedgwood 
(1771 - 1805) an Englishman who made good ground creating Photograms and recording images from his Camera Obscura or pinhole camera, However, he never overcome the problem of fixing
the image and therefore the prints produced had to be viewed for very short periods of time in a darkened environment.




IMPORTANT DATES IN THE STUDY OF PHOTOGRAPHY:

16th century 
Brightness and clarity of camera obscuras improved by enlarging the hole inserting a telescope lens


17th century
Camera obscuras in frequent use by artists and made portable in the form of sedan chairs

1727

Professor J. Schulze mixes chalk, nitric acid, and silver in a flask; notices darkening on side of flask exposed to sunlight. Accidental creation of the first photo-sensitive compound.


1800
Thomas Wedgwood makes "sun pictures" by placing opaque objects on leather treated with silver nitrate; resulting images deteriorated rapidly, however, if displayed under light stronger than from candles.

1816

Nicéphore Niépce combines the camera obscura with photosensitive paper

1826

Niépce creates a permanent image

1827

Joseph Nicephore Niepce made the first known photographic image using the camera obscura. The camera obscura was a tool used by artists to draw.


1834
Henry Fox Talbot creates permanent (negative) images using paper soaked in silver chloride and fixed with a salt solution. Talbot created positive images by contact printing onto another sheet of paper.

1837

Louis Daguerre creates images on silver-plated copper, coated with silver iodide and "developed" with warmed mercury; Daguerre is awarded a state pension by the French government in exchange for publication of methods and the rights by other French citizens to use the Daguerreotype process.

1841

Talbot patents his process under the name "calotype".


1851
Frederick Scott Archer, a sculptor in London, improves photographic resolution by spreading a mixture of collodion (nitrated cotton dissolved in ether and alcohol) and chemicals on sheets of glass. Wet plate collodion photography was much cheaper than daguerreotypes, the negative/positive process permitted unlimited reproductions, and the process was published but not patented.

1853

Nadar (Felix Toumachon) opens his portrait studio in Paris

1854

Adolphe Disderi develops carte-de-visite photography in Paris, leading to worldwide boom in portrait studios for the next decade


1855
Beginning of stereoscopic era

1855-57

Direct positive images on glass (ambrotypes) and metal (tintypes or ferrotypes) popular in the US.

1861

Scottish physicist James Clerk-Maxwell demonstrates a color photography system involving three black and white photographs, each taken through a red, green, or blue filter. The photos were turned into lantern slides and projected in registration with the same color filters. This is the "color separation" method.

1861-65

Mathew Brady and staff (mostly staff) covers the American Civil War, exposing 7000 negatives


1868
Ducas de Hauron publishes a book proposing a variety of methods for color photography.

1870

Center of period in which the US Congress sent photographers out to the West. The most famous images were taken by William Jackson and Tim O'Sullivan.
1871

Richard Leach Maddox, an English doctor, proposes the use of an emulsion of gelatin and silver bromide on a glass plate, the "dry plate" process.
1877

Eadweard Muybridge, born in England as Edward Muggridge, settles "do a horse's four hooves ever leave the ground at once" bet among rich San Franciscans by time-sequenced photography of Leland Stanford's horse.

1878

Dry plates being manufactured commercially.

1880

George Eastman, age 24, sets up Eastman Dry Plate Company in Rochester, New York. First half-tone photograph appears in a daily newspaper, the New York Graphic.


1888
First Kodak camera, containing a 20-foot roll of paper, enough for 100 2.5-inch diameter circular pictures.


1889
Improved Kodak camera with roll of film instead of paper

1890

Jacob Riis publishes How the Other Half Lives, images of tenement life in New york City

1900

Kodak Brownie box roll-film camera introduced.

1902

Alfred Stieglitz organizes "Photo Secessionist" show in New York City


1906
Availability of panchromatic black and white film and therefore high quality color, separation color photography. J.P. Morgan finances Edward Curtis to document the traditional culture of the North American Indian.

1907

First commercial color film, the Autochrome plates, manufactured by Lumiere brothers in France


1909
Lewis Hine hired by US National Child Labor Committee to photograph children working mills.

1914

Oscar Barnack, employed by German microscope manufacturer Leitz, develops camera using the modern 24x36mm frame and sprocketed 35mm movie film.

1917

Nippon Kogaku K.K., which will eventually become Nikon, established in Tokyo.

1921

Man Ray begins making photograms ("rayographs") by placing objects on photographic paper and exposing the shadow cast by a distant light bulb; Eugegrave;ne Atget, aged 64, assigned to photograph the brothels of Paris

1924

Leitz markets a derivative of Barnack's camera commercially as the "Leica", the first high quality 35mm camera.


1925
André Kertész moves from his native Hungary to Paris, where he begins an 11-year project photographing street life


1928
Albert Renger-Patzsch publishes The World is Beautiful, close-ups emphasizing the form of natural and man-made objects; Rollei introduces the Rolleiflex twin-lens reflex producing a 6x6cm image on rollfilm.; Karl Blossfeldt publishes Art Forms in Nature

1931

Development of strobe photography by Harold ("Doc") Edgerton at MIT

1932

Inception of Technicolor for movies, where three black and white negatives were made in the same camera under different filters; Ansel Adams, Imogen Cunningham, Willard Van Dyke, Edward Weston, et al, form Group f/64 dedicated to "straight photographic thought and production".; Henri Cartier-Bresson buys a Leica and begins a 60-year career photographing people; On March 14, George Eastman, aged 77, writes suicide note--"My work is done. Why wait?"--and shoots himself.

1933

Brassaï publishes Paris de nuit

1934

Fuji Photo Film founded. By 1938, Fuji is making cameras and lenses in addition to film.


1935
Farm Security Administration hires Roy Stryker to run a historical section. Stryker would hire Walker Evans, Dorothea Lange, Arthur Rothstein, et al. to photograph rural hardships over the next six years. Roman Vishniac begins his project of the soon-to-be-killed by their neighbor Jews of Central and Eastern Europe.


1936
Development of Kodachrome, the first color multi-layered color film; development of Exakta, pioneering 35mm single-lens reflex (SLR) camera World War II: Development of multi-layer color negative films Margaret Bourke-White, Robert Capa, Carl Mydans, and W. Eugene Smith cover the war for LIFE magazine


1940s 
In the early 1940's commercially viable color films (except Kodachrome, introduced in 1935) were brought to the market. These films used the modern technology of dye-coupled colors in which a chemical process connects the three dye layers together to create an apparent color image.

1947

Henri Cartier-Bresson, Robert Capa, and David Seymour start the photographer-owned Magnum picture agency


1948
Hasselblad in Sweden offers its first medium-format SLR for commercial sale; Pentax in Japan introduces the automatic diaphragm; Polaroid sells instant black and white film

1949

East German Zeiss develops the Contax S, first SLR with an unreversed image in a pentaprism viewfinder
1955

Edward Steichen curates Family of Man exhibit at New York's Museum of Modern Art

1959

Nikon F introduced.
1960

Garry Winogrand begins photographing women on the streets of New York City.
1963

First color instant film developed by Polaroid; Instamatic released by Kodak; first purpose-built underwater introduced, the Nikonos

1970

William Wegman begins photographing his Weimaraner, Man Ray.


1972
110-format cameras introduced by Kodak with a 13x17mm frame


1973
C-41 color negative process introduced, replacing C-22


1975
Nicholas Nixon takes his first annual photograph of his wife and her sisters: "The Brown Sisters"; Steve Sasson at Kodak builds the first working CCD-based digital still camera


1976
First solo show of color photographs at the Museum of Modern Art, William Eggleston's Guide
1977

Cindy Sherman begins work on Untitled Film Stills, completed in 1980; Jan Groover begins exploring kitchen utensils

1978

Hiroshi Sugimoto begins work on seascapes.

1980

Elsa Dorfman begins making portraits with the 20x24" Polaroid.

1982

Sony demonstrates Mavica "still video" camera

1983

Kodak introduces disk camera, using an 8x11mm frame (the same as in the Minox spy camera)


1985
Minolta markets the world's first autofocus SLR system (called "Maxxum" in the US); In the American West by Richard Avedon

1988
Sally Mann begins publishing nude photos of her children
1987

The popular Canon EOS system introduced, with new all-electronic lens mount


1990
Adobe Photoshop released.

1991
Kodak DCS-100, first digital SLR, a modified Nikon F3

1992

Kodak introduces Photo CD


1993
Founding of photo.net (this Web site), an early Internet online community; Sebastiao Salgado publishes Workers; Mary Ellen Mark publishes book documenting life in an Indian circus.


1995
Material World, by Peter Menzel published.


1997
Rob Silvers publishes Photomosaics


1999
Nikon D1 SLR, 2.74 megapixel for $6000, first ground-up DSLR design by a leading manufacturer.

2000

Camera phone introduced in Japan by Sharp/J-Phone
2001

Polaroid goes bankrupt

2003
Four-Thirds standard for compact digital SLRs introduced with the Olympus E-1; Canon Digital Rebel introduced for less than $1000

2004

Kodak ceases production of film cameras
2005

Canon EOS 5D, first consumer-priced full-frame digital SLR, with a 24x36mm CMOS sensor for $3000; Portraits by Rineke Dijkstra




Digital photography 
It uses an array of electronic photo detectors to capture the image focused by the lens, as opposed to an exposure on photographic film.

Emulsion 

A mixture of two or more liquids that are normally immiscible (nonmixable or unblendable). Emulsions are part of a more general class of two-phase systems of matter called colloids.

Exposure 
It is the amount of light per unit area (the image plane illuminance times the exposure time) reaching a photographic film, as determined by shutter speed, lens aperture and scene luminance.

Film Speed 

Understood as the measure of a photographic film's sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system.

Forensic Photography (forensic imaging)(crime scene photography)
It is the art of producing an accurate reproduction of a crime scene or an accident scene using photography for the benefit of a court or to aid in an investigation.


Gelatin 

It is used to hold silver halide crystals in an emulsion in virtually all photographic films and photographic papers.

Infrared Photography 
The film or image sensor used is sensitive to infrared light.

Latent Image 
It is an invisible image produced by the exposure to light of a photosensitive material such as photographic film.

Louis Daguerre 

A Frenchman and A professional scene painter,  was able to reduce exposure time to less than 30 minutes and keep the image from disappearing afterwards. He was the inventor of the first practical process of photography.

Mugshot (police photograph)(booking photograph) 

It is a photographic portrait typically taken after a person is arrested.

Negative 

It is an image, usually on a strip or sheet of transparent plastic film, in which the lightest areas of the photographed subject appear darkest and the darkest areas appear lightest.

Parallax 

It is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those
two lines.

Photography 

It is a method of recording images by the action of light, or related radiation, on a sensitive material.

Photographic Film (Film) 
It is a strip or sheet of transparent plastic film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals.

Point-and-Shoot Camera (compact camera) 

It is a still camera designed primarily for simple operation.[1] Most use focus free lenses or
autofocus for focusing, automatic systems for setting the exposure options, and have flash units built in.

Rogues Gallery 

It is a police collection of pictures or photographs of criminals and suspects kept for identification purposes.

Shutter Lag 

It is the delay between triggering the shutter and when the photograph is actually recorded.

Shutter Speed (exposure time) 

It is the length of time a camera's shutter is open when taking a photograph.

Silver Halides 

The light-sensitive chemicals used in photographic film and paper.

Single-Lens Reflex Camera (SLR) 

Typically uses a mirror and prism system (hence "reflex", from the mirror's reflection) that permits
the photographer to view through the lens and see exactly what will be captured, contrary to viewfinder cameras where the image could be significantly different from what will be captured.


Snapshot 
It is popularly defined as a photograph that is "shot" spontaneously and quickly, most often without artistic or journalistic intent.
Twin-Lens Reflex Camera (TLR) -
Is a type of camera with two objective lenses of the same focal length.

Viewfinder 

Is what the photographer looks through to compose, and in many cases to focus, the picture.

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