"Photography" is derived from the Greek words photos ("light") and graphein ("to draw") The word

was first used by the scientist Sir John F.W. Herschel in 1839. It is a method of recording images
by the action of light, or related radiation, on a sensitive material.

Pinhole Camera

Alhazen (Ibn Al-Haytham), a great authority on optics in the Middle Ages who lived around
1000AD, invented the first pinhole camera, (also called the Camera Obscura} and was able to
explain why the images were upside down. The first casual reference to the optic laws that made
pinhole cameras possible, was observed and noted by Aristotle around 330 BC, who questioned
why the sun could make a circular image when it shined through a square hole.

The First Photograph

On a summer day in 1827, Joseph Nicephore Niepce made the first photographic image with a
camera obscura. Prior to Niepce people just used the camera obscura for viewing or drawing
purposes not for making photographs. Joseph Nicephore Niepce's heliographs or sun prints as they
were called were the prototype for the modern photograph, by letting light draw the picture.

Niepce placed an engraving onto a metal plate coated in bitumen, and then exposed it to light. The
shadowy areas of the engraving blocked light, but the whiter areas permitted light to react with
the chemicals on the plate. When Niepce placed the metal plate in a solvent, gradually an image,
until then invisible, appeared. However, Niepce's photograph required eight hours of light exposure
to create and after appearing would soon fade away.

Louis Daguerre

Fellow Frenchman, Louis Daguerre was also experimenting to find a way to capture an image, but
it would take him another dozen years before Daguerre was able to reduce exposure time to less
than 30 minutes and keep the image from disappearing afterwards.

The Birth of Modern Photography

Louis Daguerre was the inventor of the first practical process of photography. In 1829, he formed
a partnership with Joseph Nicephore Niepce to improve the process Niepce had developed.

In 1839 after several years of experimentation and Niepce's death, Daguerre developed a more
convenient and effective method of photography, naming it after himself - the daguerreotype.

Daguerre's process 'fixed' the images onto a sheet of silver-plated copper. He polished the silver
and coated it in iodine, creating a surface that was sensitive to light. Then, he put the plate in a
camera and exposed it for a few minutes. After the image was painted by light, Daguerre bathed
the plate in a solution of silver chloride. This process created a lasting image, one that would not
change if exposed to light.

In 1839, Daguerre and Niepce's son sold the rights for the daguerreotype to the French
government and published a booklet describing the process. The daguerreotype gained popularity
quickly; by 1850, there were over seventy daguerreotype studios in New York City alone.

Negative to Postive Process

The inventor of the first negative from which multiple postive prints were made was Henry Fox
Talbot, an English botanist and mathematician and a contemporary of Daguerre.
Talbot sensitized paper to light with a silver salt solution. He then exposed the paper to light. The
background became black, and the subject was rendered in gradations of grey. This was a
negative image, and from the paper negative, Talbot made contact prints, reversing the light and
shadows to create a detailed picture. In 1841, he perfected this paper-negative process and called
it a calotype, Greek for beautiful picture.

Tintypes

Tintypes, patented in 1856 by Hamilton Smith, were 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.

Wet Plate Negatives

In 1851, Frederick Scoff Archer, an English sculptor, invented the wet plate negative. 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.

Photography advanced considerably when sensitized materials could be coated on plate glass.
However, wet plates had to be developed quickly before the emulsion dried. In the field this meant
carrying along a portable darkroom.

Dry Plate Negatives & Hand-held Cameras

In 1879, the dry plate was invented, a glass negative plate with a dried gelatin emulsion. Dry
plates could be stored for a period of time. Photographers no longer needed portable darkrooms
and could now hire technicians to develop their photographs. Dry processes absorbed light quickly
so rapidly that the hand-held camera was now possible.

Flexible Roll Film

In 1889, George Eastman invented 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.

Color Photographs

In the early 1940s, 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

Photographic Films

The first flexible roll films, dating to 1889, were made of cellulose nitrate, which is chemically
similar to guncotton. A nitrate-based film will deteriorate over time, releasing oxidants and acidic
gasses. It is also highly flammable. Special storage for this film is required.

Nitrate film is historically important because it allowed for the development of roll films. The first
flexible movie films measured 35-mm wide and came in long rolls on a spool. In the mid-1920s,
using this technology, 35-mm roll film was developed for the camera. By the late 1920s, medium-
format roll film was created. It measured six centimeters wide and had a paper backing making it
 easy to handle in daylight. This led to the development of the twin-lens-reflex camera in 1929.
Nitrate film was produced in sheets (4 x 5-inches) ending the need for fragile glass plates.

Triacetate film came later and was more stable, flexible, and fireproof. Most films produced up to
the 1970s were based on this technology. Since the 1960s, polyester polymers have been used for
gelatin base films. The plastic film base is far more stable than cellulose and is not a fire hazard.

Today, technology has produced film with T-grain emulsions. These films use light-sensitive silver
halides (grains) that are T-shaped, thus rendering a much finer grain pattern. Films like this offer
greater detail and higher resolution, meaning sharper images.

 Film Speed (ISO) — An arbitrary number placed on film that tells how much light is needed
to expose the film to the correct density. Generally, the lower the ISO number, the finer
grained and slower a film. ISO means International Standards Organization. This term replaces
the old ASA speed indicator. The slower the film, the more light is needed to expose it.

Photographic Prints

Traditionally, linen rag papers were used as the base for making photographic prints. Prints on this
fiber-base paper coated with a gelatin emulsion are quite stable when properly processed. Their
stability is enhanced if the print is toned with either sepia (brown tone) or selenium (light, silvery
tone).

Paper will dry out and crack under poor archival conditions. Loss of the image can also be due to
high humidity, but the real enemy of paper is chemical residue left by photographic fixer. In
addition, contaminants in the water used for processing and washing can cause damage. If a print
is not fully washed to remove all traces of fixer, the result will be discoloration and image loss.

 Fixer (Hypo)—A chemical, sodium thiosulfate, used to remove residual silver halides
(grain) from films and prints when processing them. Fixer "fixes" the remaining silver halides in
place on either film or prints. Fixer is also called hypo.

The next innovation in photographic papers was resin-coating, or water-resistant paper. The idea
is to use normal linen fiber-base paper and coat it with a plastic (polyethylene) material, making
the paper water-resistant. The emulsion is placed on a plastic covered base paper. The problem
with resin-coated papers is that the image rides on the plastic coating, and is susceptible to fading.

At first color prints were not stable because organic dyes were used to make the color image. The
image would literally disappear from the film or paper base as the dyes deteriorate. Kodachrome,
dating to the first third of the 20th century, was the first color film to produce prints that could last
half a century. Now, new techniques are creating permanent color prints lasting 200 years or
more. New printing methods using computer-generated digital images and highly stable pigments,
offer permanency for color photographs.

By definition a camera is a lightproof object, with a lens, that captures incoming light and directs
the light and resulting image towards film (optical camera) or the imaging device (digital camera).
All camera technology is based on the law of optics first discovered by Aristotle. By the mid-1500s
a sketching device for artists, the camera obscura (dark chamber) was common. The camera
obscura was a lightproof box with a pinhole (later lens were used) on one side and a translucent
screen on the other. This screen was used for tracing by the artists of the inverted image
transmitted through the pinhole.

Around 1600, Della Porta reinvented the pinhole camera. Apparently he was the first European to
publish any information on the pinhole camera and is sometimes incorrectly credited with its
invention.

Johannes Kepler was the first person to coin the phrase Camera Obscura in 1604, and in 1609,
Kepler further suggested the use of a lens to improve the image projected by a Camera Obscura.

Daguerreotype Cameras

The earliest cameras used in the daguerreotype process were made by opticians and instrument
makers, or sometimes even by the photographers themselves. The most popular cameras utilized
a sliding-box design. The lens was placed in the front box. A second, slightly smaller box, slid into
the back of the larger box. The focus was controlled by sliding the rear box forward or backwards.
A laterally reversed image would be obtained unless the camera was fitted with a mirror or prism
to correct this effect. When the sensitized plate was placed in the camera, the lens cap would be
removed to start the exposure.

Box Camera

George Eastman. a dry plate manufacturer from Rochester, New York, invented the Kodak camera.
For $22.00, an amateur could purchase a camera with enough film for 100 shots. After use, it was
sent back to the company, which then processed the film. The ad slogan read, "You press the
button, we do the rest." A year later, the delicate paper film was changed to a plastic base, so that
photographers could do their own processing.

Eastman's first simple camera in 1888 was a wooden, light-tight box with a simple lens and
shutter that was factory-filled with film. The photographer pushed a button to produce a negative.
Once the film was used up, the photographer mailed the camera with the film still in it to the
Kodak factory where the film was removed from the camera, processed, and printed. The camera
was then reloaded with film and returned.

Flashlight Powder

Blitzlichtpulver or flashlight powder was invented in Germany in 1887 by Adolf Miethe and
Johannes Gaedicke. Lycopodium powder (the waxy spores from club moss) was used in early flash
powder.

Flashbulbs

The first modern photoflash bulb or flashbulb was invented by Austrian, Paul Vierkotter. Vierkotter
used magnesium-coated wire in an evacuated glass globe. Magnesium-coated wire was soon
replaced by aluminum foil in oxygen. On September 23, 1930, the first commercially available
photoflash bulb was patented by German, Johannes Ostermeier. These flashbulbs were named the
Vacublitz. General Electric made a flashbulb called the Sashalite.

Filters - Frederick Charles Luther Wratten (1840-1926)

In 1878, Wratten invented the "noodling process" of silver-bromide gelatin emulsions before
washing. In 1906, Wratten with the assistance of Dr. C.E. Kenneth Mees (E.C.K Mees) invented
and produced the first panchromatic plates in England. Wratten is best known for the photographic
filters that he invented and are still named after him - Wratten Filters. Eastman Kodak purchased
his company in 1912.

35mm Cameras

As early as 1905, Oskar Barnack had the idea of reducing the format of film negatives and then
enlarging the photographs after they had been exposed. As development manager at Leica, he
was able to put his theory into practice. He took an instrument for taking exposure samples for
cinema film and turned it into the world's first 35 mm camera: the 'Ur-Leica'.

Polaroid or Instant Photos

Polaroid photography was invented by Edwin Herbert Land. Land was the American inventor and
physicist whose one-step process for developing and printing photos created instant photography.
The first Polaroid camera was sold to the public in November, 1948.

Disposable Camera

Fuji introduced the disposable camera in 1986. We call them disposables but the people who make
these cameras want you to know that they're committed to recycling the parts, a message they've
attempted to convey by calling their products "single-use cameras."

Digital Camera

In 1984, Canon demonstrated first digital electronic still camera.