There are many types of cameras. All of them can be classified according to the following features:
- the sensor
- the viewing system (LCD screen, single lens reflex, twin lens reflex...);
- the rigidity of the body (rigid, swivelling lens, telescopic tube, folding, monorail...);
- the focusing system (autofocus, rangefinder focusing, manual reflex focusing, guess focusing, ground glass back...);
- the lens attachment (interchangeable lens, non interchangeable zoom lens, fixed lens);
- the metering system: metering sensor and metering modes (programmed, speed-priority, aperture-priority, manual).
The features that will most determine the aspect of the camera are the viewing system and the rigidity. Once they are known, the general shape of the body is usually quite predictable.
The size of the sensor matters for the size of the camera and for the end result, while its nature has an incidence on the internal construction: a film camera usually needs place for the supply and take up spools, except for the cameras using cut film or plate film.
Unusual combinations of these features have existed, for example folding TLRs, subminiature SLRs and so on. However not every combination does make sense. For example an subminiature folding autofocus TLR is not theoretically impossible, but unlikely to ever exist.
Below is a table with common camera types and the features that distinguish them.
|sensor||viewing system||rigidity||focusing system||lens||metering system||example|
(single lens reflex)
|any||reflex finder through the taking lens||usually rigid||manual reflex focusing or autofocus||usually interchangeable||any|
(twin lens reflex)
|analog||any||reflex finder through a second lens||usually rigid||manual reflex focusing||usually fixed||manual exposure or no meter at all|
|point-and-shoot||any||up to 4.5×6cm||optical finder or LCD screen||rigid or swivelling||autofocus or fixed focusing||non interchangeable (fixed or zoom)||automatic exposure or no exposure control (single shutter speed)|
|rangefinder||any||optical finder with superimposed or separate rangefinder||rigid or folding||manual rangefinder focusing||fixed or interchangeable (no zoom)||any|
|viewfinder||analog||any||in- or external finder or ground glass back||rigid or telescopic||distance symbols or no focusing aid||usually fixed||any|
|analog||any||internal reflecting type finder or frame finder or telescopic optical finder or ground glass back||rigid||ground glass back made as sliding box, ground glass with focusable lens, or no focusing aid||fixed||none|
|folding||analog||any||reflecting type finder or internal optical finder or ground glass back or frame finder||folding||rangefinder, ground glass back or no focusing aid||fixed or interchangeable (no zoom)||any|
|subminiature||any||smaller than 18×24mm||any||any||any||any||any|
|view camera||any||ground glass back||bellows and rails||ground glass back||interchangeable||none|
|pinhole camera||any||any||any||any||pinhole "lens"||none|