Digital Photography/Digital Camera Types and Accessories
This section explains the various camera types and accessories available on the market. It does not attempt to categorize all available accessories - that's impossible - but attempts to describe the generic types of cameras and accessories available.
Buying a camera 
Types of digital cameras 
Broadly speaking Digital cameras can be segregated into two major types: Consumer and Digital Single Lens Reflex (DSLR). A third type, the Prosumer camera, usually offers all the features of the consumer camera with some of the features of the DSLR.
- Digital Consumer Cameras
- These are made as an all-in-one device. They typically have a fixed lens, and are often loaded with a lot of gimmicks to make them attractive to the average consumer. Consumer cameras can be roughly divided in two subcategories:
- These are generally designed with form in mind over functionality, and are designed to have a high form-factor for the stylish crowd. They tend to have very basic user control or have predefined modes, and often don't allow for much manual adjustments. Typically, these cameras have more pixels and lower image quality.
- These cameras are a good choice if you always want to have your camera with you; they tend to have good form-factor and are lightweight, and most of them can fit into your pocket. Point-and-Shoot cameras can be used without any special knowledge, so they are attractive for those who just want to document events in their lives and do not want go deep into technical aspects of photography.
- High-end Consumer Cameras
- These have additional manual control features to allow more creativity and flexibility. For the photography enthusiast, these tend to be the bridge between Point-and-Shoot, and the almost inevitable progression to Digital SLR.
- In fact, some of these cameras try to look like Digital SLR cameras but do not have interchangeable lenses and Through The Lens viewfinder. As they are built with components similar to those found in the Point-and-Shoot cameras, they also suffer from the technical limitations of the Point-and-Shoot cameras. However, better quality control and the use of better optics means these camera can deliver images that are quite good.
- If you have a limited budget and still want to get some of the effects like DOF (Depth Of Field) in your shots then you must select the camera which provides the option of Aperture and Shutter Priority shooting Modes. You can select the model based after trying your hand to click using these settings at the shop. There are many Digital Consumer Camera which have these facilities. Th
- Digital Single Lens Reflex Cameras (Digital SLR)
- These have Through The Lens viewfinder, and typically have an interchangeable lens (there are a few digital SLRs which have fixed lenses. In general, however, SLR cameras, both traditional and digital, will have interchangeable lenses). The image sensors on digital SLRs are much larger and of a different construction than on consumer cameras and contributes to higher image quality.
- Digital SLR focuses on giving high manual control to the user, and when combined with possibility to change lenses, gives a high degree of flexibility to the user. Entry-level Digital SLRs usually have several different automatic modes (similar to Consumer cameras) to make them less intimidating for beginners.
- The high degree of quality control and the array of high-quality optic lenses has a correspondingly huge drawback: cost. A Digital SLR tends to cost a good deal, and a professional level Digital SLR can be 10 to 20 times the cost of a Consumer camera.. before adding the cost of the lens.
- Digital Prosumer Cameras
- 'Prosumer' is a term coined by the media and picked up by the industry to describe cameras that are professional in quality but yet sold at consumer prices. It can also be used to describe users of said cameras.
- As such, Prosumer cameras can be either High-end Consumer cameras, or Digital SLR. The key distinguishing factor is high quality at a low price band, and not so much the type of camera.
- As a practical example, Nikon's D70, a Digital SLR, is generally talked of as a prosumer camera model, and/ or as an entry-level Digital SLR. At the same time, Nikon's recent addition to their Coolpix series are largely SLR-like cameras which are also considered prosumer due to their quality.
- In recent years, as the technology in digital photography progressed and matured, Nikon in particular has been pushing more models into the prosumer market. In a similar vein, Canon has also been pushing their digital camera models in this direction in direct competition. Other manufacturers like Sony and Fujifilm are pushing more towards the Point-and-Shoot market, with more emphasis on form-factor and ease-of-use rather than on pushing the capability of their cameras.
- As such, while more prosumer cameras are on the market, these are largely from very well established manufacturers that has extensive experience in camera manufacturing. At the same time, a slew of Point-and-Shoot cameras are coming on the market, some from companies which have very little experience in this industry.
Memory Cards 
Nearly all digital cameras have an SD-Slot and many newer cameras can use the SDHC-Cards up to 32GB. So the memory card type should not be the deciding factor when purchasing a camera. However, if you have other digital devices that use memory cards like an Smartphone, then this may factor into your decision, because not only will this allow you to save some the cost of duplicate sets of cards, but it may allow you directly view the photographs on your Smartphone.
That being said, here is a list of the most popular memory card formats:
(SDHC) are widely available in a wide range of sizes (up to 32GB) and are cheaper than CompactFlash (CF).
Because of their smaller size, they are available in many cameras from entry-level up to DSLR-Cameras. There is also newer SDXC standard that allows for up to 2TB capacity, many newer devices since 2010 do support these cards.
There is also older SD standard that allows for up to 2GB capacity, which is supported by many older devices. SDHC and SDHC devices are backward compatible and SD(HC/XC) cards are forward compatible.
(CF) cards are widely available in a wide range of sizes (up to 32GB) and are cheaper per megabyte than other standard media. Most prosumer cameras now use CF. CF cards come in two varieties:
- CF Type I - 3.3 mm thick. Cameras designed for CF Type I can't use CF Type II.
- CF Type II - 5 mm thick. Cameras which use CF Type II also can use CF Type I. Some manufacturers are selling Microdrives (mini hard drives) packaged in the CF II format. If your camera supports the CF Type II format it may also support the Microdrive.
Multi Media Card (MMC) are similar to SD card from outside, but not compatible with SD cards.
xD-picture Card (xD) are developed by Fuji and Olympus. They are very compact in size, but usually about two times more expensive than CF or SD cards.
Memory Stick (MS) are used by most Sony cameras, and only by Sony Cameras. Most of MS cards are produced by Sony (the only other manufacturers are SanDisk and Lexar) this factor influence rather high prices of MS cards Memory Stick Duo (MS Duo) variant which is smaller in size, and can be used with regular MS card cameras via adapter.
When buying a digital camera the safe bet is to choose camera which can use CompactFlash, SDXC or SDHC cards. Some cameras can use two different types of cards (e.g. Olypus E-5 and Canon EOS 1D Mark IV can use CompactFlash and Secure Digital cards).
Battery Life 
Digital compact cameras with no optical viewfinder need much more power than other cameras, because the LCD display is the largest power consumer.
Nearly all digital cameras come with rechargeable Li-ion batteries. Some DSLR cameras like the Pentax K-x use standard Mignon batteries and the most DSLR cameras can be attached to a battery grip, which can hold multiple batteries.
Non-rechargeable batteries refer to the common batteries cells, commonly available in a variety of sizes. Non-rechargeable batteries are not recommended, because most batteries (or cells) are designed to discharge gradually over time; digital cameras draw power in bursts, which quickly exhausts ordinary batteries. There are batteries designed specifically for digital camera usage, but these tend to be expensive.
Rechargeable batteries have one additional advantage, and that's universal compatibility. You can go to pretty much any country and recharge them with a universal charger supporting 110-230V.
Other Accessories 
Card Readers 
Most cameras come with a USB connection which you use to transfer digital images from the camera to your computer. If you are lucky, both your computer and your camera use the USB 2 specification. Some older cameras use the slower USB 1 specification, or slower yet, your computer's COM port to transfer images. A device that can speed things up is a USB card reader, which can be purchased at an electronics store, usually for less than the price of one memory card alone. Most card readers support more than one card type; just make sure it supports the card type you use. When you wish to transfer the images from the card to the computer, connect the card reader to your computer, pop the card into the card reader, and copy the images from the card to the computer by using file drag and drop.
Many laptop and netbook computers made by Dell, Acer, Asus, and other manufacturers now have built-in card readers. Some support only SD cards, while others support a wider variety. These small card readers seldom support CompactFlash, due to that card's large size and the fact that CF cards can be read using an inexpensive PC card adapter.
Lens Filters 
Among the first accessories a serious photographer considers is lens filters. There are many filters available for DSLR lenses, less so for fixed lens cameras. Lens filters have a threaded mount that screws onto the front of a lens. They work by modifying the light before it passes through the lens for a wide range of interesting and useful effects.
When you buy a lens filter you need to buy the correct size for your lens size. Look for the a number on the front of your lens, some common lens sizes are 52mm and 55mm. Many camera shops carry the more common sizes. If yours does not, you may want to contact the manufacturer of your lens if you have a DSLR, or of your camera if you have a fixed lens camera.
A word of caution applies to using colored lens filters with digital photography. Colored (e.g. orange, red and blue) filters work by limiting the light of a given color passing through the lens; using a blue filter compensates for a yellowish cast; using an orange filter compensates for a bluish cast. These are used mainly with film photography for color balance, but since almost all digital cameras have an automatic white balance, the effect of a colored filter will not be the same as with film. In addition some new prosumer cameras have built in filter effects so using an additional colored filter would never be necessary.
Some common and interesting lens filters are:
Infrared Filter or IR Filter. This filter reduces visible light and allows IR light to pass through the lens; the filter itself appears black or reddish-black. Infrared images can appear ghostly or other-worldly simply because Infrared radiates and reflects off objects differently than does visible light.
Diffusion Filter. A diffusion filter is a translucent photographic filter used for a special effect. When used in front of the camera lens, a diffusion filter softens subjects and generates a dreamy haze. This can also be improvised by smearing petroleum jelly on a UV filter or shooting through a nylon stocking. Diffusion filters may be uniform or may have a clear center area to create a vignette of diffused area around the clear center subject.
Diffusion filters are also used in stage lighting (and likewise in photography setups), where they may also be called diffusion gel, or just diffusion. This is a reference to color gel, which is another type of lighting gel. Diffusion gels soften the light in order to reduce or diffuse shadows or glare.
Silk sheets can also be used in this manner, and in fact were until the invention of translucent plastics. "Opal" is a common translucent or opalescent diffusion.'
Polarizing Filter. This filter is made of polarizing glass that rotates freely in a circular ring. A polarizing filter cuts down on reflected light from some angles while allowing light from other angles to pass through the filter. The effect of a polarizing filter is to darken either the sky or reflections off leaves or water depending on the position of the filter. The effect can be quite pronounced and appealing. For more information on how polarizing filters work, see Polarization
UV Filter. This filter cuts down on UV rays that can make your photograph appear hazy or excessively bluish on bright days. UV filters come in a range of strengths. TIP: To protect the front element of that expensive lens you've purchased, get a mild-strength UV filter and screw it onto the lens. The cost of the filter is very small in comparison to the cost of the lens and having the filter always in place can protect the front lens element with the added benefit of reducing haze whenever you use the lens. Note: There is considerable controversy on the actual protection a filter supplies to a lens in the event that it dropped. Shards of glass can be very damaging to the surface of the lens. Many will argue that a lens hood will provide significantly more protection to the front element of a lens AND help reduce the effects of flare and loss of contrast from strong side lights (to which filters are prone).
Tripods are three legged devices used to support a camera to provide stability and greatly improve the quality of photographs. A single-legged tool that serves the same function is referred to as a monopod. Because a tripod can remove almost all camera motion, the quality of a tripod is almost as important as the quality of the lens. The cost of a tripod can vary by an amazing amount. Flimsy tripods are less stable, durable, flexible, and may even be heavier than a high-quality tripod.