The conventional camera depended entirely on chemicals and mechanical processes - nothing else was required to make them work. Following along on the footsteps of major technological breakthroughs in consumer electronics, the new digital camera is part of this fundamental shift in technology.
The digital camera has two things: a built-in computer, and electronic recorded images. They have not entirely replaced the conventional camera, though, as film represents the highest quality of pictures.
The early digital cameras were used to store images on memory devices within the camera, then transferring the images to the computer with the help of cables. Today, most digital camera makers provide reusable and removable storage devices, such as SmartMedia cards, CompactFlash, cards and Memory Sticks. Some other removable storage devices include the floppy disks, hard disks, or micro-drives, writeable CDs and DVDs. This has considerably enhanced the volume of visual data that can be stored.
A digital camera uses light converted into electrical charges, instead of film, to take pictures. It focuses this light through a lens or a series of lenses onto a sensor, which records the image electronically. The sensor used the most is employed by a CCD (charge coupled device) while others use a CMOS (complementary metal oxide semiconductor).
If a CCD is used to transport the charge, its sensors create a high-quality, low-noise image, while the CMOS are more susceptible to noise while traditionally using less power. The CCDs consume as much as 100 times more power than that of a CMOS yet have been mass-produced for a longer time. They have a higher number of higher quality pixels yet both play the same role - they turn light into electricity.
What every photographer is looking for is clarity and high detail, with very little blurriness or a grainy look. This has to do with the resolution of the camera, which refers to the amount of detail the camera can capture. Hewlett Packard estimates that a 35mm film is about 20 million pixels, considered a very high-resolution picture - 1216 x 912, or 2 million total pixels, is a photo lab quality for the 4 x 5 picture.
To break it down even more, a 1 megapixel digital camera will produce images that are good for e-mailing or posting on the Web because their resolution is low. The images taken from a 2-megapixel camera are suitable for 4x5 inch prints while those taken from a 4-megapixel camera can produce 16x20 inch prints.
The digital cameras use four kinds of lenses. These are: fixed-focus, fixed-zoom lenses; optical-zoom lenses with automatic focus; digital-zoom lenses, and replaceable lens systems. The fixed focus and fixed zoom lenses are used in inexpensive cameras while the optical zoom lenses have both wide and telephoto options. The aperture and shutter speed are used to control the amount of light that reaches the sensor.
The aperture setting, or the size of the opening in the camera, is automatic in most digital cameras but a few allow manual adjustment. This is because certain professionals or amateurs want more control over the final image. The shutter speed is the time amount that passes through the aperture. This can be set electronically, which is different than using film in the conventional 35mm cameras. The digital camera has a digital shutter, rather than a mechanical shutter.
Overall, the digital camera and the traditional film camera have the same principals. The both have a viewfinder for aiming the camera, the lens for focusing, the ability to store several images and remove them later on, with a compact format for everything's storage.
Two different systems yet slightly the same - the conventional camera captured images with light-sensitive film to store them after chemical development, while the digital camera used memory storage and advanced image sensor technology, capturing images to store them in digital format that is instantly available instead of having to wait. Yet the digital camera is more environmentally friendly, keeping up with the issues of the world while photographing these issues at the moment they occur.
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