In a relatively short period of time, digital cameras came onto the scene and rapidly replaced film cameras as the dominant type of camera. Even though digital cameras have become cheap, consumers still need to be informed when buying them. Understanding the basics of how they work, resolution, zoom and other factors is a great help when making a purchasing decision.
How they store images
In many ways, a digital camera is much like a regular film camera. Just as in a film camera, a digital camera has a series of lenses to focus the light to create an image of the scene someone is taking of picture of. However, instead of creating the image on film, a digital camera focuses it on a semiconductor that is made up of tiny photosites that are light sensitive. Called pixels, these dots measure the light and record all the details of it in number form. These numbers, basically just a long string of 1s and 0s, can then be put together by a computer to create a picture that can be stored, sent and manipulated electronically.
Pixels
While it was once necessary to pay a premium to get enough pixels for a quality image, this is no longer the case as the number of pixels digital cameras offer has increased and costs decreased. As a general rule, around five megapixels is enough resolution to print out an A4 image with roughly the same detail a 35mm film camera can offer.
Those who intend to print out lager images should have cameras with more megapixels, however, most digital cameras now offer more than enough pixels even for larger prints. Also, keep in mind that one or two megapixels are all that most computer screens can display. Taking pictures in too many pixels will create images that take more memory and that must be reduced in size before they can be emailed or used online. With cameras now offering so many pixels, it is advisable to set them at a lower than maximum pixel setting for most uses. Around six megapixels offers plenty of resolution and a more manageable image size.
Zoom
When considering zoom, be aware that digital zoom is more of a marketing gimmick than a real zoom. All a digital zoom actually does is to enlarge the central area of the picture to make it appear closer, sacrificing resolution in the process.
While this might be enough for simple family pictures, an optical zoom is needed to take landscape photos with good resolution even when using a digital camera. Buy used film cameras
Memory
With flash memory now very cheap, memory is no longer a major factor when purchasing a digital camera. SD and other memory devices offer ways to store large amounts of digital data very cheaply.
Other functions
Since the basic functions of digital cameras are similar to film apart from the storage of images (although they of course offer extra functions like video), most of what one should look for in buying a digital camera is the same as for any camera. Design, feel of the camera, size and how the camera will be used are very important factors.
Image stabilization is an excellent feature that is now available on many cameras. By compensating for a shaky hand or subject that is moving, it helps the amateur photographer avoid blurring and other distortion.
Face detection is another great feature. By finding the center of the image, it takes a lot of the guess work out of taking pictures.
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