Digital Cameras

A digital camera captures video and still photographs digitally as it records images on a light sensitive sensor. These cameras can also record sound and moving video in addition to still photographs. Digital cameras are responsible for the demise of the conventional 35 mm film camera which was widely in use until recent times.

The evolution of the digital camera can be traced back to the early 1980's when Sony Corporation released its Sony Mavica electronic still camera. This camera was one of the first commercial electronic cameras which recorded images onto a mini disc and these were then put on a video reader which was connected to a television monitor or a color printer. This video camera which took video freeze frames was one of the earliest digital cameras.

The Kodak Company which was a leading light in the field of cameras until then had also begun to produce many solid state image sensors that converted light into digital images. In 1986 the scientists at Kodak, invented the world's first mega pixel sensor which was capable of recording 1.4 million pixels and which could produce 5x7 inch digital photo quality prints. The scientists at Kodak continued to experiment with these cameras and in 1991 the company launched the first professional digital camera system which was aimed for use by photojournalists. This camera was essentially a Nikon F-3 camera which was equipped with a 1.3 mega pixel sensor. The revolution in the world of digital cameras had thus begun and soon in the mid nineties several models of digital cameras were launched in quick succession such as the Apple Quick Take 100 camera, the Sony Cyber Shot digital still camera and the Kodak DC40 camera. These cameras worked to store images on a home computer via a serial cable. These cameras were then aggressively marketed and they soon became ubiquitous as they easily replaced the traditional film cameras for both commercial and professional uses.

Digital cameras score over traditional cameras in various spheres, for instance they are capable of displaying an image on the camera's screen immediately after capturing the image, they also have the capacity to record a large number of images on a small memory device and hence tend to be far more economical than traditional film cameras. Moreover these cameras also have the ability to record sound with video and also allow a user to edit and delete images according to their preferences and hence score easily over the traditional film cameras. These digital cameras are nowadays incorporated into a number of devices like cell phones and PDAs.

Compact digital cameras are also known popularly as 'Point and Shoot' cameras. These cameras are designed to be easily portable and easy to use. They usually sacrifice advance features and picture quality for the ease of use and simplicity of interface. They store pictures as JPEG images which use Lossy compression. When you use a ' point and shoot' camera you don’t see the real image formed by the camera lens but you are able to get a rough idea of the image in the camera's view finder. Most 'point and shoot' cameras are automatic where everything is controlled by a microprocessor instead of the photographer. The central microprocessor in the camera processes the information it receives from the autofocus system and the light meter, as it activates several motors which adjust the lens and open and close the aperture.

Higher end digital cameras are called SLR cameras. In an SLR camera you can actually see the real image as is captured by the lens of the camera. In an SLR camera a slanted mirror is positioned between the shutter and the lens and piece of translucent glass and a prism is also placed above it. The real image then bounces off the lower mirror onto the translucent glass which projects the image onto the prism. The prism then flips the image on the screen so it appears correctly in the viewfinder window. The working of the mirror and the translucent screen present the real image exactly how it will appear. The advantage of such a mechanism is that you can then adjust the focus and compose the scene according to your wish. It is for this reason that SLR cameras are used typically by professionals.

According to popular surveys and estimates the Canon Powershot series of digital cameras are the most popular digital cameras in the Point and Shoot category of cameras and this is again repeated in the case digital SLR cameras where the Canon EOS digital Rebel XT series leads in popularity when compared with the Nikon D series of SLR cameras.