Views: 9
INTRODUCTION
A camera is one of the scientific most valuable tools. Cameras can be attached to many other advanced optical instruments e.g. microscopes in biology or telescopes used in astronomy. When fixed to microscopes, cameras can reveal very fine details that the resolution of human eye cannot see. In fact, such specialized photography is becoming essential for scientific research as the information gathered by them can be reproduced in magazines and books with great accuracy. These enables scientist to share their experiences with others. Remote control cameras can be used to take photographs from positions that are too dangerous e.g. sites of atomic bombs or explosions or even sites that are too small for man to go e.g. in the throat and the stomach to give the doctor the detailed information about these internal organs. Photographic evidence is generally regarded as truthful and accurate e.g. in any court of law when dealing with criminal cases and other forensic matters. In fact, no center of medical, industrial or scientific research would be properly equipped without a photographic facility.
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. The diameter of the aperture is often controlled by a diaphragm mechanism, but some cameras have a fixed-size aperture. Most cameras use an electronic image sensor to store photographs on flash memory. Other cameras, particularly the majority of cameras from the 20th century, use photographic film.
A typical still camera takes one photo each time the user presses the shutter button (except in continuous-fire mode). 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.