Photography

Photography is the art and practice of creating images by recording light. It can be done electronically, using an image sensor, or chemically, using a light-sensitive material such as photographic film. Photography is used in many fields of science, in manufacturing (for example, photolithography), and in business. It is also used for art, video production, mass communication, and fun or hobbies. A person who uses a camera to take photographs is called a photographer. The picture that is made is also called a photograph, and it is the result produced by the camera.

A lens is usually used to focus light from objects onto the light-sensitive surface inside a camera. The light is let in for a short, timed exposure. With an electronic image sensor, this creates an electrical charge at each pixel. The charge is electronically processed and stored in a digital image file that can be shown or changed later. With photographic emulsion, the result is an invisible latent image. This image is later chemically developed into a visible image, either a negative or a positive, depending on the purpose of the material and the method of processing. A negative on film was once used to make a positive image on paper, called a print, either by using an enlarger or by contact printing.

Before digital photography became common, film photographs had to be developed to make negatives or slides. Negatives then had to be printed as positive images, often in a larger size. Photographic laboratories usually did this work. Many amateur photographers, students, and photographic artists developed their own photographs.

Etymology

The word "photography" comes from two Greek words: phōs, meaning "light," and graphé, meaning "drawing." Together, they mean "drawing with light."

Several people may have come up with the word on their own. Hércules Florence, a French painter and inventor who lived in Brazil, used the French form, photographie, in private notes. A Brazilian historian believes these notes were written in 1834. This idea is widely reported, but it is not yet accepted everywhere. In 1839, the German newspaper Vossische Zeitung published an article called Photographie. This is the earliest known use of the word in print. The astronomer John Herschel is also said to have created the word in 1839. The inventors Nicéphore Niépce, Henry Fox Talbot, and Louis Daguerre do not seem to have used the word "photography." They gave their methods other names, such as "Heliography," "Photogenic Drawing," and "Daguerreotype."

History

Main articles: History of photography and Timeline of photography technology

See also: History of the camera

Main article: Photographic film

Main article: Monochrome photography

See also: Black-and-White

Main article: Color photography

Main article: Digital photography

See also: Digital camera

Photography grew from several discoveries about how images can be seen and captured. The camera obscura ("dark chamber" in Latin) dates back to ancient China. Later, Ibn al-Haytham (Alhazen) invented the first true pinhole camera. His work helped lay the groundwork for photography, which was invented in the 19th century. Early inventors then worked on ways to capture and keep an image. In 1802, Thomas Wedgwood made the first known attempt, but his images faded. In 1826, Nicéphore Niépce took the View from the Window at Le Gras, the oldest surviving photograph of a view from nature. Later, Louis Daguerre worked with Niépce and developed the daguerreotype process, which was announced in 1839. In Britain, William Fox Talbot created the calotype process, which made a negative that could be used to print many copies. John Herschel was the first to use the words "photography", "negative" and "positive."

Flexible roll film was first sold by George Eastman, founder of Kodak, in 1885. Color photography was explored from the 1840s. The Autochrome was the first color process that sold well, introduced by the Lumière brothers in 1907. Kodachrome followed in 1935. In 1991, Kodak introduced the DCS 100, the first digital single-lens reflex camera sold to the public. Film was the main form of photography until the early 21st century, when digital cameras became more popular. Today, most photographs around the world are taken with digital cameras, and more and more often with smartphones.

Techniques

Photographers use many tools and materials to capture images. The camera forms the image, and the image can be recorded on a photographic plate, photographic film, or a silicon image sensor. Photographers control the light that reaches this material to create a "latent image" or a RAW file in digital cameras. That data is then turned into a picture we can use. Digital cameras use sensors such as a charge-coupled device (CCD) or complementary metal–oxide–semiconductor (CMOS) technology. Painters first used the camera obscura in the 1500s. A movie camera takes a fast series of pictures called "frames." When these are played back, our eyes and brain blend them together so they look like motion.

Main article: Camera

Main article: Stereoscopy

Stereoscopic photography uses two slightly different images side by side to create a 3D effect. It was the first method to capture moving figures. Photographers can also take pictures from both sides of a device at once. This is called dualphotography. Other methods use infrared film or ultraviolet film. Digital cameras can also be changed to record more of the light spectrum. This is called full spectrum photography. Newer "light field" methods let photographers choose the focus after taking a picture. They use microlenses at each pixel. Some images are made without a camera. Examples include photograms made from shadows on photographic paper, or pictures made by placing objects on an image scanner.

Types

Amateur photographers take photos for fun or personal interest, not as a job. Their work can be as good as that of many professionals. Hand-held cameras helped amateur photography grow in the late 1800s. Today, social media and camera phones make taking pictures common. Newer smartphone cameras have automatic features like color management, autofocus, face detection, and image stabilization. These features make good photos easier to take. Commercial photographers are paid for their images. Their work includes architectural photography, event photography, concert photography, food photography, landscape photography, and wildlife photography. Advertising photos are made to sell a product or service.

Main article: Art photography

During the 1900s, fine art photography and documentary photography became accepted in the art world. Some people argued about whether photography counts as art, because it can be a mechanical copy of an image. Conceptual photography turns an idea into a photograph, even though the objects shown are real. Photojournalism uses pictures to tell news stories. It must be honest and fair. It can also include sports photography. Photography has long helped science. Cameras have recorded events like eclipses, and tiny creatures through photomicroscopy. Cameras also help record crime scenes and accidents. The methods used to study photos for legal cases are called forensic photography.

Main article: Photojournalism

Further information: Forensic photography

Main article: Wildlife photography

Wildlife photography means capturing images of animals and other living things in nature. Unlike many other kinds of photography, it requires the photographer to pick the right place and time, when the wildlife is present and active. It often takes great patience and skill.

Social and cultural implications

There are many open questions about photography. In her On Photography (1977), Susan Sontag doubts that photographs are objective. She says that taking a photo is a way of controlling what is shown. Photographers choose what to shoot, what to leave out, and what angle to use. So photography can be a personal way of showing the world. It is also one of the new media forms that changes how people see and how society is shaped.

Photography has raised concerns about its effect on society. In Alfred Hitchcock's Rear Window (1954), the camera is shown as encouraging people to spy on others. Digital pictures can raise ethical concerns because they are easy to change. Today, image editing is simple, even for beginners. Many photojournalists say they will not crop their pictures or join parts of several photos into "photomontages" that are passed off as "real" photographs. Some newer cameras can use digital fingerprinting to detect changes made to photos. This helps forensic photography. Some people also worry that upsetting images, such as photos of war, may be seen by children and society at large. Tourism is another area where photography shapes society. It can create a "tourist gaze," in which local people are seen and defined through the camera lens.

Law

In many places, the law both limits and protects photography. Photographs are usually protected by giving the photographer copyright or moral rights. In the United States, photography is protected as a First Amendment right. Anyone may photograph things they can see in public places. In the UK, a law from 2008, the Counter-Terrorism Act, gives the police more power to stop people, including press photographers, from taking pictures in public places.

In South Africa, anyone may photograph another person in public places without asking first. The only special limit the government places on photography is for things linked to national security. Each country has its own laws.