Digital - CamerasDigital cameras Think about the method the camera uses for storing image data. If the output devices printers and projectors use the card as storage device, so images stored can be output straight away in these devices. Unlike traditional cameras which store images on film, digital cameras use a small sensor chip - either CCD (Charged Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor). - The image is stored in a digital format. The surface of the CCD or CMOS is divided into tiny squares known as pixels. Each pixel records one part of an image. The greater the number of pixels that can be recorded, the greater the detail that can be captured. A megapixel is a million pixels. The number of pixels a digital camera has is a good measure of the details the digital camera can contain. Picture quality is also effected by other factors such as the lens, the colour filter used on the sensor and the digital image processor. To understand the concept of digital photography it may help to consider the way in which humans see images. The process of creating a digital photograph involves light going through the lens of the camera, in the same way that light travels through the lens in a human eye. This light is collected as electrical charges by a sensor like the retina of a human eye. The image processor of the camerais like the brain, it processes the image data before storing the image onto a memory card. The camera has to carry out all these stages well to ensure good results in terms of image quality. What about memory cards? The images that are captured with a digital camera are stored on a memory card. Larger capacity cards enables more images to be stored. For example a 512MB card will store over 100 high quality images. Zoom, zoom, zoom! Many digital cameras have zoom lens. These are described as optical zooms or digital zooms. Optical zooms give a true idea of what a camera is capable of, where as digital zooms simply enlarge the central part of an image to give the illusion that the photographer has zoomed in. The image quality goes down and the pixels that make up the image are easier to see. Power Digital cameras use a fair amount of battery power to deliver all their advanced features, so it is important to make sure that the choose a model with a rechargeable battery system. Price The prices of digital cameras has dropped in recent years however in terms of performance you get what you pay for. For around £80 you can get an entry level, point and shoot compact camera, but if you want advanced features then you would probably expect to pay £200 or upwards. Overall when choosing a digital camera remember megapixels aren't everything. Consider the lens and CCD as well! |
| | Home | |
| Copyright © 2005 Ecodigital Ltd. Registered in England and Wales No. 5554365. VAT No. 867 3706 88. Registered Address: Clarence Street Chambers, 32 Clarence Street, Southend-on-Sea, Essex. SS1 1BD. |




