Digital+Still+Cameras

All digital cameras have a built in computer, and record images electronically. A digital image is a group of different coloured pixels that collectively make an image. The higher the resolution of the image, the more pixels can be on the screen. 1 Pixel also is one value and is represented on the final image produced as a colour. (You can see this by zooming into an image far enough until it pixalates, From there you can see each individual colour and shade which when added together produce the final colour with shadows/highlights etc)

A digital camera directly samples the original light that bounces off the subject, breaking the light pattern down into a series of pixel values. It has a series of lenses that focus light to create an image. However, while a conventional film camera focuses this light onto a piece of film, a digital camera focuses it onto a semiconductor device that stores light electronically. A computer then breaks down this electronic information into digital data.

The image sensor used by most digital cameras is a charge coupled device (CCD). However, some digital cameras use a complemantary metal oxide semiconductor (CMOS). Both CCD and CMOS image sensors convert light into electrons.


 * A CCD transports the charge across the chip and reads it at one corner of the array. An analog-to-digital converter (ADC) then turns each pixel's value into a digital value by measuring the amount of charge at each photosite and converting that measurement to binary form.
 * CMOS devices use several transistors at each pixel to amplify and move the charge using more traditional wires.