It seems there is a new camera launched every day - actually it's far more than that! However, pretty well all cameras fit into some broad categories. This article takes you through some of the more common ones - stick with us and you'll soon know your bridge from your DSLR.
Ultra compact
As the name suggests, you're looking at very small cameras here. The size of ultra compacts tends to have settled down now - it's about the size of a credit card. What really sets the ultra compacts apart from the compacts is the thickness - or “thinness” as the ad agencies like to call it. This ranges from the “so thin you might snap it” (check out the Sony DSC-T7 or the Casio EX-S500 which are less than 15mm “thin”) to the comparatively chunky which are over 20mm. Any of these should slip easily into all but the tightest jeans pocket. Interestingly thin cameras have been getting thicker lately. Manufacturers seem to have lost their drive to produce the thinnest ever - the Sony T9 is a good few millimetres thicker than the T7 which it replaces.
It's very rare for an ultra compact to have a viewfinder at all - pictures are composed and viewed on the rear LCD. LCDs are getting bigger sharper and clearer even in sunlight.
You might be surprised that the ultra compacts tend to have more features than compacts. The reason is simple - they cost more. It costs quite a lot to make a camera very small so the manufacturers tend to have more to spend on little “luxuries” like all metal bodies and extra scene modes. Expect to pay between £250 and £380 for an ultra compact. You can also pretty well bet that the lens will be in the 38 - 135mm range. Some go wider and some longer but that's the general lens you can fit in a body this small. Controls on an ultra compact tend to be limited to automatic or an ever increasing range of scene modes.
Compacts
Like an ultra compact but bigger! Length and width tend to be similar to an ultra compact but the body is thicker and tends to protrude even when the camera is turned off. If you want to take a compact around with you then you'll probably need to slip it into a jacket pocket or a larger handbag rather than a trouser pocket or clutch bag.
The compact category varies wildly form the least expensive digital cameras to some of the most advanced small cameras around. The extra bulk allows the designers to pack in more “bits” such as optical viewfinders and longer zooms. It also allows them to use cheaper materials for the body and in some cases use regular AA batteries rather than a custom rechargeable.
Compact cameras tend to be made from plastic and lenses can range anywhere from 30mm to 300mm though the general range is about the same as ultra compacts. Expect to pay between £130 and £300 for a compact. Controls will be similar to an ultra compact though it's not uncommon to find compacts that also allow you shoot in aperture or shutter priority and some support manual mode.
Bridge cameras
This is where it starts to get complicated. A bridge camera tends to look more like, well a camera. There's usually a noticeable lens with the rest of the camera effectively bolted to the back. Bridge cameras are supposed to “bridge” the gap between compact cameras and DSLRs and allow you to take much more control of how you take your pictures. Pretty well all bridge cameras will have manual controls as well as aperture and shutter priority and scene modes.
Many of them will also let you zoom the lens by turning a collar rather than pressing the “W” and “T” buttons. Some even go so far as to have manual focussing rings. You may also get handy features such as a viewfinder. Some of these are optical (you look through a little window) but most are electronic viewfinders (EVF). This is really just a small extra LCD screen but generally have a rubber surround so that you can block out the light and look through them. They also mean that you can hold the camera more “correctly” for maximum stability.
Since the designers aren't hampered by looks or size the zooms can get very big. We've seen bridge cameras with lenses that go as wide as 24mm and as long as 420mm (though not yet in the same camera). To carry on our theme - you'll need a jacket with big pockets or a small bag to carry a bridge camera.
Bridge cameras are often seen as the “poor relation” of DSLRs and to some extent that's true. They tend to be slower to focus and of course you can't change the lens. However they have a couple of advantages - they tend to be smaller and cheaper and are sealed so that dust can't get inside. Manufacturers are now piling on the features so it's not unusual to see a bridge camera that can be used with studio flash and take pictures in a variety of challenging environments.
Expect to pay somewhere between £220 and £450 for a bridge camera though falling DSLR prices are driving bridge prices down.
dSLR
This is where most of the serious action is now as manufacturers fight for market share. Technically a DSLR (“digital single lens reflex”) means only that when you look through the viewfinder the view you get is through the lens. A clever mirror and prism system transmits the view through the lens to your eye. This allows for very accurate viewing of the scene and allows you to see the picture as it will be taken. They are much easier to view than even the best LCD screens but when you take pictures in the dark the view is, well, dark. On none through the lens cameras most amplify the screen or EVF in the dark so you can see better. Note that on DSLRs you cannot view the scene on the LCD before you take the picture - it is for menus and for reviewing shots you have already taken. The only exception to this at the moment is the Olympus E330 which uses some very fancy optics and electronics to present a live view on the LCD.
DSLRs also tend to allow you to change the lens. (Actually they all do now - there were some older cameras that were DSLRs with non changeable lenses but currently all cameras that let you view through the lens also let you change the lens). This is one of the reasons why the manufacturers love them - you are not buying a camera you are buying a system. A Nikon lens will not fit a Canon and vice versa. The companies know that once you have 3 or 4 lenses you are much less likely to change brand. The ability to change lens brings huge advantages - today you can fit a super wide lens that is optimised for landscapes. Tomorrow you can change to a huge zoom for wildlife shots or a macro for flowers or use an ultra fast prime lens and take low light pictures. This flexibility is one of the reasons why nearly all professionals shooting digitally use a DSLR.
The sensor in a DSLR is also bigger than in other cameras. Again this doesn't have to be so but it always is. Sensors on compact and bridge cameras have a diagonal length somewhere between 5 and 11mm. DSLRs start at around 23mm and go up to about 43mm (which is the same as 35mm film). Bigger in this case is generally better - a bigger sensor generally has less noise than an equivalent smaller sensor. However, the most important difference is in depth of field. All else being equal, the larger the sensor the smaller the depth of field. This allows DSLR users to take pictures where only portions of them are in focus (“selective focusing”) which tends to be very hard on compact and bridge cameras. By comparison, even the best pictures on a smaller sensor can tend to look like snapshots where everything is in focus from front to back.
DSLRs also respond much more quickly than even bridge cameras both in terms of autofocus and general readiness to take a picture - this makes them ideal for fast moving activities. Bridge cameras can be used for sports but even a basic DSLR will generally be easier to use.
DSLRs start at around £350 and go up to several thousands. That's without a lens (“body only”). Often you can buy them with a kit lens but high quality lenses can easily cost more than the camera. It is sensible to budget for the body being about ½ - 2/3 of the cost of your “starter kit” - expect to spend at least half as much again on lenses, memory, extra batteries and general accessories. As you've probably guessed, these aren't the kind of camera you can slip in a pocket - you'll need a bag. Sometimes quite a big bag by the time you've bought extra lenses etc.
Others
There are of course other kinds of digital cameras. Rangefinders, medium format digital, swivel bodied compacts, cameras built into binoculars etc... However, most of the cameras we see here at ThinkCamera will fit into one of the categories discussed.
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