Camera
Content
Camera
A camera is a device that records images. These images may be still photographs or moving images such as videos
or movies. The term camera comes from the camera obscura (Latin; "camera" is a "vaulted chamber/room" +
"obscura" means "dark"= "darkened chamber/room"), an early mechanism for projecting images. The modern
camera evolved from the camera obscura.
Cameras may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A
camera generally consists of an enclosed hollow with an opening (aperture) at one end for light to enter, and a
recording or viewing surface for capturing the light at the other end. A majority of cameras have a lens positioned in
front of the camera's opening to gather the incoming light and focus all or part of the image on the recording surface.
Most 20th century cameras used photographic film as a recording surface, while modern ones use an electronic
camera sensor. The diameter of the aperture is often controlled by a diaphragm mechanism, but some cameras have
a fixed-size aperture.
A typical still camera takes one photo each time the user presses the shutter button. A typical movie camera
continuously takes 24 film frames per second as long as the user holds down the shutter button, or until the shutter
button is pressed a second time.
History
Camera obscura.
The forerunner to the camera was the camera obscura.[1] The camera obscura is an instrument consisting of a
darkened chamber or box, into which light is admitted through a convex lens, forming an image of external objects
on a surface of paper or glass, etc., placed at the focus of the lens.[2] The camera obscura was described by the
Arabic scientist Ibn al-Haytham (Alhazen) in his Book of Optics (1015–1021).[3] The actual name of camera
obscura was applied by mathematician and astronomer Johannes Kepler in his Ad Vitellionem paralipomena of
1604. He later added a lens and made the apparatus transportable, in the form of a tent.[4][5] Irish scientist Robert
Boyle and his assistant Robert Hooke developed a portable camera obscura in the 1660s.[6]
The first camera obscura that was small and portable enough for practical use was built by Johann Zahn in 1685. At
this time there was no way to preserve the images produced by these cameras apart from manually tracing them.
However, in 1724, Johann Heinrich Schultz discovered that a silver and chalk mixture darkens under exposure to
light. Early photography built on these discoveries and developments. The early photographic cameras were
essentially similar to Zahn's camera obscura, though usually with the addition of sliding boxes for focusing. Before
each exposure, a sensitized plate would be inserted in front of the viewing screen to record the image. The first
permanent photograph was made in 1826 by Joseph Nicéphore Niépce using a sliding wooden box camera made by
Charles and Vincent Chevalier in Paris and building on Johann Heinrich Schultz's discovery about silver and chalk
mixtures darkening when exposed to light. Jacques Daguerre's popular daguerreotype process utilized copper plates,
while the calotype process invented by William Fox Talbot recorded images on paper.
The first permanent colour photograph, taken by James Clerk Maxwell in 1861.
The development of the collodion wet plate process by Frederick Scott Archer in 1850 cut exposure times
dramatically, but required photographers to prepare and develop their glass plates on the spot, usually in a mobile
darkroom. Despite their complexity, the wet-plate ambrotype and tintype processes were in widespread use in the
latter half of the 19th century. Wet plate cameras were little different from previous designs, though there were some
models, such as the sophisticated Dubroni of 1864, where the sensitizing and developing of the plates could be
carried out inside the camera itself rather than in a separate darkroom. Other cameras were fitted with multiple
lenses for making cartes de visite. It was during the wet plate era that the use of bellows for focusing became
widespread.
The first color photograph was made by Scottish physicist James Clerk Maxwell, with the help of English inventor
and photographer Thomas Sutton, in 1861[7]
The electronic video camera tube was invented in the 1920s, starting a line of development that eventually resulted
in digital cameras, which largely supplanted film cameras after the turn of the 21st century.
Camera Types
There are several ways to categorize cameras (and paper, and film…). The main division are by film format and
body types.
Format
The first major division is by format, or film size.
Miniature
The most commonly available miniature cameras use the APS, or Advanced Photo System. This is a cartridge film
in a 16 x 24mm format. The idea behind APS is that the film is encoded with exposure data, which is used by
dedicated film processors to yield (hopefully) better negatives and prints. APS is mostly used for point-and shoot.
Also in this category is the Minox, a true spy camera. with an 8 x 11mm image. Minox use is a true specialty, and a
near cult thing.
Small
This is 35mm (or 135), which gives a 24 x 36mm negative. 126 format also fits into this category, which is the
Kodak Instamatic. These cameras are usually modular, easy to handle and use.
Medium
Medium format ranges from 6 x 4 cm to 6 x 8 cm. Medium combines the ease of use of the 35mm with a larger
negative size. Mostly used by professionals, the medium format is also generally modular, allowing lens, back,
viewfinder, and other cool stuff to be switched out as the need arises and budget allows. The most famous of
medium format is the Hasselblad.
Large
Large format runs generally from 4 x 5 inches up to 16 x 20”. The large format is the bulkiest and hardest type to
use, but offers incredible image control, with the ability to move both the film plane and the lens plane
independently
Body Type
Each of these may be found using more than a single format, as mentioned in the descriptions. As well, I am
describing more specific types than usual.
Point and Shoot
Usually found in 35mm format, although also using the 110 cartridge, point and shoots are designed to be extremely
simple to use. With better technology at lower costs, these cameras are now often quite sophisticated. The point and
shoot is typified by ease of use. Load the film, point it and press the shutter release. Most have minimal viewfinders,
fixed exposure and fixed focus. The current most basic of this type is the single-use cameras, which are the same
idea as the original consumer camera, the Kodak Brownie.
Table of Contents:
Single Use Cameras
Compact Lens-Shutter Cameras
Bridge Cameras
Rangefinders
Twin Lens Reflex
SLR (Single Lens Reflex)
Single Use Cameras
Single Use Cameras are the simplest cameras. They contain a roll of color film encased in a recyclable cardboard
box. They have a single shutter speed and a fixed-focus lens. These cameras can be bought with a variety of
features, including built-in flash and water resistance. The whole camera has to be taken to the photo finisher so the
film can be processed. The camera is recycled. These cameras cost around $15 and should not be used for serious
photography. They are convenient for vacations and times when you find that the other camera has been forgotten.
Compact Lens-Shutter Cameras
Compact Lens-Shutter Cameras come in three varieties: single focal length, dual focal length, and zoom. Some have
fixed focus, meaning that the focus is fixed at a point that produces sharp images starting from about 5 ft. away and
continuing to infinity. Other cameras offer infrared auto focusing. Some models offer features like red-eye reduction
flash and several automatic shooting modes. More serious photographers usually prefer to have more control over
the pictures they take.
Bridge Cameras
Bridge cameras are intermediate cameras. They bridge the gap between "point and shoot" cameras and the more
serious or complicated models. They have different lenses and many offer a red-eye reducing flash. There is only a
limited range of lens focal length that can be used with these cameras.
Rangefinders
Rangefinders are compact, lightweight cameras that are often used for serious photography. They offer
interchangeable lenses and allow photographers to control shutter speed, lens aperture, focusing, and exposure.
Some disadvantages are that it is limited in focal length (ranging from 21mm-135mm) and they tend to be
expensive.
Twin Lens Reflex
The twin lens reflex is a medium-format camera (one that uses film larger that 35mm). It is fitted with two lenses
which both have the same focal length, one mounted atop the other. The lower (taking) lens focuses its image
directly on the film, while the image produced by the upper viewing lens is reflected through 90 degrees by a mirror,
and brought to focus on a horizontal ground-glass focusing screen. The light paths to the focusing screen and the
film plane are equal, so that if the photographer brings the scene on the focusing screen to sharp focus, the image on
the film plane will be equally sharp.
Single Lens Reflex
The SLR requires one lens for both viewing and creating the photo. A sophisticated camera that offers full manual
control of exposure an focus. SLR cameras will accept interchangeable lenses, add on flashes, motor drives, and
other accessories. There are also AF (auto focus) SLR's. These can be set in a number of different modes to ease
picture taking. These cameras are typically used by professional photographers.
Common Components
Firstly, let's look at what cameras have in common. Except for some specialist types of camera, all cameras have the
following basic components:
Body: A light-tight compartment to house the recording medium (film or CCD).
Lens: A transparent element to focus light rays onto the recording medium.
Aperture: A method of controlling how much light reaches the recording medium.
Shutter: A method of controlling how long the recording medium is exposed to the incoming light.
Viewfinder: A way to see the image that is to be captured.
Transport: In film cameras, a method of moving the film and holding it in the correct position.
A camera is a device that records images. These images may be still photographs or moving images such as videos
or movies. The term camera comes from the camera obscura (Latin; "camera" is a "vaulted chamber/room" +
"obscura" means "dark"= "darkened chamber/room"), an early mechanism for projecting images. The modern
camera evolved from the camera obscura.
Cameras may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A
camera generally consists of an enclosed hollow with an opening (aperture) at one end for light to enter, and a
recording or viewing surface for capturing the light at the other end. A majority of cameras have a lens positioned in
front of the camera's opening to gather the incoming light and focus all or part of the image on the recording surface.
Most 20th century cameras used photographic film as a recording surface, while modern ones use an electronic
camera sensor. The diameter of the aperture is often controlled by a diaphragm mechanism, but some cameras have
a fixed-size aperture.
A typical still camera takes one photo each time the user presses the shutter button. A typical movie camera
continuously takes 24 film frames per second as long as the user holds down the shutter button, or until the shutter
button is pressed a second time.
History
Camera obscura.
The forerunner to the camera was the camera obscura.[1] The camera obscura is an instrument consisting of a
darkened chamber or box, into which light is admitted through a convex lens, forming an image of external objects
on a surface of paper or glass, etc., placed at the focus of the lens.[2] The camera obscura was described by the
Arabic scientist Ibn al-Haytham (Alhazen) in his Book of Optics (1015–1021).[3] The actual name of camera
obscura was applied by mathematician and astronomer Johannes Kepler in his Ad Vitellionem paralipomena of
1604. He later added a lens and made the apparatus transportable, in the form of a tent.[4][5] Irish scientist Robert
Boyle and his assistant Robert Hooke developed a portable camera obscura in the 1660s.[6]
The first camera obscura that was small and portable enough for practical use was built by Johann Zahn in 1685. At
this time there was no way to preserve the images produced by these cameras apart from manually tracing them.
However, in 1724, Johann Heinrich Schultz discovered that a silver and chalk mixture darkens under exposure to
light. Early photography built on these discoveries and developments. The early photographic cameras were
essentially similar to Zahn's camera obscura, though usually with the addition of sliding boxes for focusing. Before
each exposure, a sensitized plate would be inserted in front of the viewing screen to record the image. The first
permanent photograph was made in 1826 by Joseph Nicéphore Niépce using a sliding wooden box camera made by
Charles and Vincent Chevalier in Paris and building on Johann Heinrich Schultz's discovery about silver and chalk
mixtures darkening when exposed to light. Jacques Daguerre's popular daguerreotype process utilized copper plates,
while the calotype process invented by William Fox Talbot recorded images on paper.
The first permanent colour photograph, taken by James Clerk Maxwell in 1861.
The development of the collodion wet plate process by Frederick Scott Archer in 1850 cut exposure times
dramatically, but required photographers to prepare and develop their glass plates on the spot, usually in a mobile
darkroom. Despite their complexity, the wet-plate ambrotype and tintype processes were in widespread use in the
latter half of the 19th century. Wet plate cameras were little different from previous designs, though there were some
models, such as the sophisticated Dubroni of 1864, where the sensitizing and developing of the plates could be
carried out inside the camera itself rather than in a separate darkroom. Other cameras were fitted with multiple
lenses for making cartes de visite. It was during the wet plate era that the use of bellows for focusing became
widespread.
The first color photograph was made by Scottish physicist James Clerk Maxwell, with the help of English inventor
and photographer Thomas Sutton, in 1861[7]
The electronic video camera tube was invented in the 1920s, starting a line of development that eventually resulted
in digital cameras, which largely supplanted film cameras after the turn of the 21st century.
Camera Types
There are several ways to categorize cameras (and paper, and film…). The main division are by film format and
body types.
Format
The first major division is by format, or film size.
Miniature
The most commonly available miniature cameras use the APS, or Advanced Photo System. This is a cartridge film
in a 16 x 24mm format. The idea behind APS is that the film is encoded with exposure data, which is used by
dedicated film processors to yield (hopefully) better negatives and prints. APS is mostly used for point-and shoot.
Also in this category is the Minox, a true spy camera. with an 8 x 11mm image. Minox use is a true specialty, and a
near cult thing.
Small
This is 35mm (or 135), which gives a 24 x 36mm negative. 126 format also fits into this category, which is the
Kodak Instamatic. These cameras are usually modular, easy to handle and use.
Medium
Medium format ranges from 6 x 4 cm to 6 x 8 cm. Medium combines the ease of use of the 35mm with a larger
negative size. Mostly used by professionals, the medium format is also generally modular, allowing lens, back,
viewfinder, and other cool stuff to be switched out as the need arises and budget allows. The most famous of
medium format is the Hasselblad.
Large
Large format runs generally from 4 x 5 inches up to 16 x 20”. The large format is the bulkiest and hardest type to
use, but offers incredible image control, with the ability to move both the film plane and the lens plane
independently
Body Type
Each of these may be found using more than a single format, as mentioned in the descriptions. As well, I am
describing more specific types than usual.
Point and Shoot
Usually found in 35mm format, although also using the 110 cartridge, point and shoots are designed to be extremely
simple to use. With better technology at lower costs, these cameras are now often quite sophisticated. The point and
shoot is typified by ease of use. Load the film, point it and press the shutter release. Most have minimal viewfinders,
fixed exposure and fixed focus. The current most basic of this type is the single-use cameras, which are the same
idea as the original consumer camera, the Kodak Brownie.
Table of Contents:
Single Use Cameras
Compact Lens-Shutter Cameras
Bridge Cameras
Rangefinders
Twin Lens Reflex
SLR (Single Lens Reflex)
Single Use Cameras
Single Use Cameras are the simplest cameras. They contain a roll of color film encased in a recyclable cardboard
box. They have a single shutter speed and a fixed-focus lens. These cameras can be bought with a variety of
features, including built-in flash and water resistance. The whole camera has to be taken to the photo finisher so the
film can be processed. The camera is recycled. These cameras cost around $15 and should not be used for serious
photography. They are convenient for vacations and times when you find that the other camera has been forgotten.
Compact Lens-Shutter Cameras
Compact Lens-Shutter Cameras come in three varieties: single focal length, dual focal length, and zoom. Some have
fixed focus, meaning that the focus is fixed at a point that produces sharp images starting from about 5 ft. away and
continuing to infinity. Other cameras offer infrared auto focusing. Some models offer features like red-eye reduction
flash and several automatic shooting modes. More serious photographers usually prefer to have more control over
the pictures they take.
Bridge Cameras
Bridge cameras are intermediate cameras. They bridge the gap between "point and shoot" cameras and the more
serious or complicated models. They have different lenses and many offer a red-eye reducing flash. There is only a
limited range of lens focal length that can be used with these cameras.
Rangefinders
Rangefinders are compact, lightweight cameras that are often used for serious photography. They offer
interchangeable lenses and allow photographers to control shutter speed, lens aperture, focusing, and exposure.
Some disadvantages are that it is limited in focal length (ranging from 21mm-135mm) and they tend to be
expensive.
Twin Lens Reflex
The twin lens reflex is a medium-format camera (one that uses film larger that 35mm). It is fitted with two lenses
which both have the same focal length, one mounted atop the other. The lower (taking) lens focuses its image
directly on the film, while the image produced by the upper viewing lens is reflected through 90 degrees by a mirror,
and brought to focus on a horizontal ground-glass focusing screen. The light paths to the focusing screen and the
film plane are equal, so that if the photographer brings the scene on the focusing screen to sharp focus, the image on
the film plane will be equally sharp.
Single Lens Reflex
The SLR requires one lens for both viewing and creating the photo. A sophisticated camera that offers full manual
control of exposure an focus. SLR cameras will accept interchangeable lenses, add on flashes, motor drives, and
other accessories. There are also AF (auto focus) SLR's. These can be set in a number of different modes to ease
picture taking. These cameras are typically used by professional photographers.
Common Components
Firstly, let's look at what cameras have in common. Except for some specialist types of camera, all cameras have the
following basic components:
Body: A light-tight compartment to house the recording medium (film or CCD).
Lens: A transparent element to focus light rays onto the recording medium.
Aperture: A method of controlling how much light reaches the recording medium.
Shutter: A method of controlling how long the recording medium is exposed to the incoming light.
Viewfinder: A way to see the image that is to be captured.
Transport: In film cameras, a method of moving the film and holding it in the correct position.
