PnS Digital Camera
How does it work?
At its most basic level, it is just like a conventional camera, it has a series of lenses that focus light to create an image of a scene. But instead of focusing this light onto a piece of film, it focuses it onto a semiconductor device that records light electronically. A computer then breaks this electronic information down into digital data. All the fun and interesting features of digital cameras come as a direct result of this process.
Who are the leading providers for the said device?
- Casio
- Canon
- HP
- Kodak
- Nikon
- Panasonic
- Samsung
- Sony
- Vivatar
How does it differ from other similar devices?
Compared to webcams, PnS cameras have more resolution giving more clarity and depth in an image. However, they don’t have internet streaming capabilities like webcams.
In comparison with video cams, PnS cameras that have video capabilities can’t still match most of the consumer video cams available in the market. Most PnS video cams only offer VGA resolution whiled dedicated video recorders offer HD quality video. In addition, PnS cameras have only mono audio quality compared to the much better stereo quality of video cameras.
What is the device used for?
PnS cameras are mostly used to capture moments and memories. Families bring cameras to get pictures of happy events and occasions. Teenagers on the other hand carry it along to their gimmicks and parties.
However, high end point and shoot cameras like the Leica D-lux 4 and the Lumix LX3, can be used not just in gatherings but also in capturing high quality images that can be used in billboards, magazines and advertisements.Digital Single Lens Reflex Camera
How does it work?
The Lens
A photograph taken with a digital single lens reflex(DSLR) camera starts at the lens. A DSLR lens is really a collection of sub-lenses called elements. Each lens refines and focuses light to create a sharp, high quality image. Lenses on DSLRs can be changed for different purposes. Wide angle lenses can be attached for landscapes. Long telephoto lenses can be used for wildlife or sports photography. Zoom lenses, or lenses that change their focal length between wide-angle and telephoto, are very common and are often included with the camera.
The Mirror, Prism & Viewfinder
What makes a DSLR unique is the mirror and pentaprism. A mirror behind the lens reflects the light upward to a 5-sided prism, or pentaprism, where it is reflected through the viewfinder. When the shutter release is pressed, the mirror just behind the lens flips up to allow a straight path between the light and the shutter. The shutter opens for the required time and the light falls on the sensor. In a DSLR what a photographer sees in the viewfinder is almost exactly what is captured by the sensor.
The Shutter & Aperture
In a DSLR, the shutter lies between the flip-up mirror and the sensor and the aperture is found in the lens. The aperture controls, by expanding and contracting, the amount of light passing through the lens. The shutter controls the amount of light falling on the sensor by remaining open for a specific amount of time. The shutter and aperture work together to allow a precise amount of light to fall on the sensor.
The Sensor
The sensor is a matrix of tiny devices that measure the intensity and color of the light allowed to fall on the sensor by the shutter. These devices are called sensor sites and are comprised of a tiny lens, a signal amplifier, and an analog to digital converter. The quality of the final image is primarily a factor of sensor quality.
In-Camera Processing
After the image has been captured by the sensor and converted into a digital form, basic image processing is done in the camera. This could include removing noise and grain inherent in the sensor, adjusting color levels to user taste, and other simple tasks that don't require the power of a desktop computer. More modern DSLRs have more powerful computers that allow more complex in-camera processing like converting an image from color to black and white.
The Memory Card
After image processing, the image is stored on a flash memory card for later retrieval by computers. Flash memory is used because it doesn't require power to store an image. Common memory cards are xD, SD, MemoryStick and Compact Flash. Once an image is on a memory card, it can be read by any computer with an appropriate card reader. Most, but not all, DSLRs use Compact Flash or SD memory.
Who are the leading providers for the said device?
As of 2008, DSLR sales are dominated by Canon's and Nikon's offerings. For 2007, Canon edged out Nikon with 41% of worldwide sales to the latter's 40%, followed by Sony and
The duopoly of Canon and Nikon is sometimes referred to as "Canikon" or "Nikanon" in online forums in skeptical challenge to the presumptive acceptance of these manufacturer's cameras as always "the best". Canon and Nikon have used their professional market presence especially persuasively in the sale of entry level offerings to the uninitiated general public who presume that everything from Canon or Nikon is superlative. Online contributors often challenge the "Canikon/Nikanon" supposed superiority when they believe there are superior innovations from the smaller DSLR manufacturers.
The DSLR market is dominated by Japanese companies, including all of the top five manufacturers (Canon, Nikon,
How does it differ from other similar devices?
Non-SLR digital cameras generally fall into two types: compact digicams, and SLR-like bridge digital cameras (also known as advanced digital cameras) which offer larger zoom ranges, better optics, and more manual controls. Both types have permanently fixed lenses. While the only defining feature of an SLR is its reflex viewfinder system, extant digital SLR models generally offer the following advantages over fixed-lens cameras of the same generation:
- Choice of interchangeable (and often higher-quality) lenses.
- Image sensors of much larger size and often higher quality, offering lower noise, which is useful in low light, and greater dynamic range.
- Optical viewfinders which tend to be more comfortable and efficient, especially for action photography and in low-light conditions.
- DSLRs often offer faster and more responsive performance, with less shutter lag, faster autofocus systems, and faster frame rates.
- The larger focal length for the same field of view allows creative use of depth of field effects.
- Ability to attach additional accessories including hot shoe-mounted flash units, battery grips for additional power and hand positions, external light meters, and remote controls
There are also certain drawbacks to current DSLR designs, compared to fixed-lens cameras:
- Generally greater size and weight.
- Generally greater cost.
- Few DSLRs with a video mode.With the exception of cameras such as the Nikon D90 and the Canon EOS 5D Mark II, few DSLRs produced so far can record full-motion video, while this has become a standard feature of compact digital cameras.
- Most DSLR models lack live preview on their LCDs, a nearly universal feature among compact digital cameras (many newer DSLRs do offer this).
- Louder operation, due to the SLR mirror mechanism.
- Potential contamination of the sensor by dust particles, when the lens is changed (though recent dust reduction systems alleviate this).
- Small digicams generally can focus better on closer objects than typical DSLR lenses.
What is the device used for?
A couple of years ago DSLR cameras were used only for making money. Unless you have a lot of extra dough these gadgets were reserved for professional photographers only. But as newer technologies develop and cheaper costs were reached, almost everyone today has a DSLR camera.
Sources
http://www.ehow.com/how-does_4911452_dslr-camera-work.html
http://electronics.howstuffworks.com/digital-camera1.htm
http://en.wikipedia.org/wiki/Digital_single-lens_reflex_camera
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