Digital Camera Buying Guide - More Choosing

There are quite a few types of memory cards, which is where all modern cameras store the photos and video they capture. The SD-HC format is by far the most common one and is also the cheapest per capacity. Nearly all non-DSLRs accept SD-HC cards and entry to mid-range DSLRs as well. The high-end format is still Compact Flash due to its potential for fast transfer speeds and high capacities.

	Compact flash memory is realively cheap, it is available in the largest capacities and the fastest speeds.
	Some cameras only accept Type 1 Compact Flash cards, which are slimmer than Type II cards. This effectively means no MicrodrivesMicrodrives are tiny hard drives. They used to be quite economical and available in large capacities, this is no longer the case. Microdrives are more fragile than memory cards and cannot operate above 10,000ft of altitude..
	This Compact Flash successor uses a high-speed interface and a smaller form-factor similar to SD cards. It offers faster read speeds (from 500 MB/s) and faster write speeds (from 125 MB/s).
	SD memory is very common and has the widest compatibility among devices such as digital photo-frames, card-readers and laptops.
	SD-HC cards are high-capacity SD cards which are generally not compatible with SD devices. SD cards can always be used where SD-HC cards are accepted. SD-HC are now the cheapest memory cards and are the most commonly accepted among digital cameras.
	SD-XC cards are extended capacity SD-HC cards that support sizes above 32GB, theoretically up to 2 TB. Any camera which accepts SD-XC cards will accept SD-HC and SD cards as well. The reverse is not true though, so SD-XC cards are only accepted in SD-XC compatible cameras and devices.
	Micro SD-HC cards are small versions of SD-HC cards. Originally used in cellular phones, some cameras come with adaptors to use a Micro SDHC card instead of their native memory type.
	Micro SD-XC cards are small versions of SD-XC cards. Although mostly common in cellular phones, some ultra-compact digital cameras accept this type of memory too.
	xD can be found in Olympus and Fuji cameras, it is one of the most expensive memories, limited in capacity and rather slow. Modenn Fuji cameras either accept both xD and SD-HC or only SD-HC. Certain Olympus cameras take Micro-SD cards using an adapter which fits in the xD slot.
	Memory Stick are used by Sony cameras and are also quite expensive. The Pro version is faster but otherwise identical.
	Memory Stick Duo is simply a smaller versionA Memory Stick Duo can be used in a Memory Stick slot using an adapter but not vice-versa. of the Memory Stick. There is also a faster Pro version.

Digital cameras preview images either using an LCD screen or a kind of viewfinder. LCD displays can be hard to see in bright light due to unwanted reflexions and exposure to direct sunlight. A viewfinder is preferable but rarely available on small cameras, particularly ultra-compact models. The general advantages of a viewfinder are that it rarely reflects stray light and it provides an extra point of stability for precise framing. There exists many types of viewfinders:

• Electronic viewfinders are tiny LCD displays that preview the image as seen by the sensor. They can be extremely accurate in terms of exposure, color, white-balance and framing. Except for those used by now-defunct Konica-Minolta, they are hard to see in low-light. Most, other than a few models by Panasonic, are also not precise enough to accurately preview image focus.
• An optical reflex viewfinder is highly recommended for night photography and continuous shooting. Judging focus is rather easy with a reflex viewfinder which is needed for precise manual focusing. On the other hand, optical viewfinders to not preview exposure, color or white-balance.
• An optical tunnel is formed using a second lens above the camera's photographic lens. It is sometimes seen on compact digital cameras. This allows coarse framing when the LCD is not usuable due to movement or bright light.

Terms

• Viewfinder coverage is the visible percentage of the final picture, the closer to 100% the better. Most EVFs and LCDs show 100% coverage but optical viewfinders generally only show 95% coverage. A 100% coverage viewfinder is found on high-end DSLRs.
• A higher magnification viewfinder shows a larger view and is preferable. It allows more comfortable viewing of the subject and better judement for focus and depth-of-field.

Regular size batteries such as "AA" are preferable. They are cheap, can easily be replaced by disposable ones, keep getting better and solar-chargers are even available.

Custom lithium-ion batteries may last longer than a single set of "AA" but you can afford several sets of "AA" for the same price as one lithium-ion battery.

Avoid cameras that charge in docks, you can't use those cameras while recharging them unless the dock can charge a spare too. Charger docks are an extra thing to carry while traveling.

Weatherproof cameras are designed to withstand adverse weather without being submerged under water. They can easily stand rain, snow and dust. This is availble on a number of DSLR models, particularly high-end ones. A weather-sealed DSLR requires the use of a weather-sealed lens to remain weather-sealed.

Waterproof cameras can actually be submerged under water up to a maximum depth dictated by the camera specifications. This is usually between 3m (10') and 10m (33'), so this is usable for swimming and snorkeling but not for SCUBA diving.

The general solution for deep immersion is to use a specially designed underwater casing. Those are generally model specific, so if this is a requirement, one must check for availability before deciding on a camera model.