Digital photography refers to the method of recording images using electronic sensors without the use of photographic film. The stored image can be transferred to a computer, displayed on a television screen, or printed using a printer.
The first digital camera, made by Steven Sasson in the 1970s, weighed almost 4 kg and was as big as a toaster. It could take a monochrome still image on a digital cassette tape with a resolution of 0.01 megapixels.
The first commercial filmless camera was the Mavica, marketed by Sony in 1981. It was based on television technology (due to which the image quality was inferior) and it used magnetic disks for storage.
Digital photography has become very popular among both amateurs and professionals since the 1990s and digital cameras now outsell conventional film cameras. They also feature additional functions such as audio and video recording. Digital photography is also used in devices other than digital cameras such as mobile phones and PDAs (personal digital assistants).
There are 2 main types of electronic sensors used in digital photography. These are
- Charge-coupled device (CCD) sensors: Most digital cameras use CCD sensors.
- CMOS sensors: Formerly used only in lower-end cameras, CMOS sensors are now used in higher-end models also, due to the development of higher-quality sensors.
Comparison with conventional film cameras
- The photograph can be viewed instantly.
- As there is no need to buy any film, there is only a one time investment on the equipment.
- Unwanted pictures can be deleted easily, thus enabling the photographer to take many shots of the subject at different setting, which would be very costly using film.
- The photograph can be reviewed and manipulated before it is finally printed out.
- The cost of storage on digital media is much lesser than on film.
- Digital camera print-outs are usually costlier per print.
- Minute details are missed out in digital photographs because film cameras are capable of taking higher resolution shots.
- Initial investment in digital equipment is very high.
- At a given cost, the quality of digital photographs is lesser than film.
- Digital photography equipment requires the use of batteries and their constant recharging, which can sometimes be inconvenient.
- They usually tend to focus incorrectly in poor lighting conditions.
- Special kinds of film for some kinds of photography (such as infrared photography) have no equivalent in digital sensors.