Digital SLRS - 11 models tested and reviewed
David Fearon
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Nov 21, 2008 5:04 PM
They may look big and complicated, but a digital slr is just as easy to use and takes far better pictures than a pocket digicam
The digital SLR camera’s time has come. Until recently, the marketing battleground was in digital compact models, but now the big guns have swung and we can reap the benefits of a huge amount of competition. There are plenty of reasons for your next digital camera to be a DSLR rather than a pocket-sized compact.
Ever find yourself shouting, “Stay there! Don’t move!” to your friends as you wait for your digital compact to wake itself up, extend its lens and finally – agonisingly – take the shot, only for the moment to have passed? Not with a DSLR. Just switch it on and take the shot – there’s almost no delay and no shutter lag, and autofocus is blindingly quick compared to compact models.
You don’t need to be scared of the apparently complex controls, either. Every DSLR on test this month has a fully automatic mode that’s no more complex than pointing the camera and pressing the shutter. And finally, there’s the price – this month’s winner is great value for money.
The ratings explained
The star ratings you’ll find at the bottom of each review are relative only to the products on test in any particular Labs. A one out of six rating doesn’t mean the product is the worst of its type to be made, just that it’s the least impressive that month. Likewise, a six out of six score isn’t necessarily an indication of perfection.
How we test
Testing digital cameras isn’t quite like testing other types of hardware. The major aspects of choosing a printer, for instance – speed, running costs and print quality – are all easily quantifiable.
Assessing a DSLR is unavoidably more subjective, so while we give the testing process a healthy dose of objective scoring, there’s inevitably more scope for personal preference. Some, for instance, may like a camera body that’s as small and portable as possible; others might find that same quality annoyingly fiddly. We try to take that into account as far as possible when we’re testing.
The basic categories of assessment we use for every Labs don’t change with DSLR testing, though. We still award each camera a mark out of six in four categories: Quality (in this case Image Quality), Features & Design, Value for Money and an Overall rating.
Image Quality
When we test digital compact cameras, we put an emphasis on the quality of the lens. With digital SLRs that can be contentious, since the lens can always be changed for a different model, and most SLRs can be bought body-only for a lot less cash. So we award each camera two overall quality scores: one Kit quality rating and one Body-only quality rating.
The Kit quality is the overall image quality with the kit lens fitted to the camera, so taking effects such as geometric distortion and chromatic aberration – which are largely caused by the lens – into account.
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| We test the stock lenses at both ends of their zoom range and at low-end ISO |
For the Body-only quality rating, we place more emphasis on image-quality aspects that reveal the abilities of the camera body itself, in particular the sensor’s high-ISO performance, exposure-metering accuracy and dynamic range. Note that the Fujifilm S5 Pro isn’t supplied in a kit with a lens, so it receives no score in the Kit quality test. Since noise performance is one of the main differentiators of DSLRs these days, we’ve teased that aspect out to give a High ISO quality rating, too.
Our DSLR tests also deviate from compact testing insofar as we adjust some settings manually to get a level playing field, rather than setting the cameras in fully automatic mode.
For outdoor testing, for example, we put each camera in aperture-priority mode and take a shot at f/5.6 at ISO 100, at both the kits lens’s maximum wide-angle and maximum zoom settings. Then, we take the same pair of shots at ISO 1600 to assess noise performance and look for signs of things such as clipped highlights, which indicate potential problems with sensor dynamic range.
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| Image quality scores |
DSLR Lenses
Probably the greatest advantage of an SLR camera is the enormous range of lenses you can use. At the basic level it simply allows different focal lengths, ranging from super-wide-angle to extreme telephoto. But there’s more to consider than just that.
Maximum aperture is a big part of a lens’s specification, and the wider the maximum the more expensive – and heavier – the lens will be. A kit lens typically has a maximum aperture of f/3.6 at wide-angle and f/5.6 at full zoom. A good aftermarket lens might offer f/2.8 across the whole zoom range.
Digital-specific lenses
Most new lenses for SLRs are now slated as being digital-specific. There are two aspects to this. Many are designed for cameras with APS-C-sized sensors, rather than full-frame 35mm. This is an important limitation, since they’re designed to project an image circle that covers only the smaller size of an APS sensor.
If you attach a designed-for-digital APS-C lens to a 35mm film camera, or a full-frame digital camera such as Canon’s EOS 5D, the result will be severe “vignetting”, with darkened corners to your images. Designed-for-digital lenses also use different coatings on their glass elements. This isn’t merely a marketing ploy to get you to buy more expensive lenses.
Digital cameras are far more prone to the effects of light bouncing around inside the lens and the camera body, because of the construction of digital sensors. To maximise the use of all available light, every pixel element of a sensor is covered by a micro-lens. These tend to pick up indirect light readily, leading to light contamination and unwanted flare effects. Digital-specific coatings are designed to absorb that stray light, reducing its effect.
In recent years, the technology behind zooms has meant that the best are extremely close in terms of quality to non-zoom “prime” lenses, and the convenience factor means new prime lenses are produced very rarely. That said, most serious amateurs and professionals still have three or four lenses in their kit bag. You’ll usually find a zoom covering the wide-angle end of the spectrum, perhaps around 10-22mm; a “middling” zoom that will cover most everyday situations, typically around 18-70mm; and a telephoto for things like wildlife photography, the most common range for these being 70-200mm or 70-300mm.
Super-zooms
A relatively new class of lenses is known as the super-zoom. The aim of these is to replace a whole bag full of lenses with one that covers the whole range of focal lengths from true wide-angle to telephoto. The first generation of super-zooms had a range of 18-200mm (28mm-320mm equivalent). Models with this range are available from Canon, Nikon, Sigma, Tamron and others. As the technology has progressed further, the range has become extreme – Tamron has an 18-270mm model, which is equivalent to a 15x zoom range.
While a super-zoom can make a great carry-around lens that’s ready for any situation (they’re particularly good for holidays where you’re not able to take your whole kit bag), they have their drawbacks. First is the fact that they’re not especially fast, usually f/3.5 at wide-angle to around f/5.6 at maximum telephoto.
That means depth-of-field effects can be more difficult to achieve, and low-light photography without camera shake can be difficult, too, especially at maximum zoom where the aperture is at its minimum and camera-shake is exacerbated by the magnification factor.
To mitigate the second of those effects, newer super-zooms feature image stabilisation. Second, because of the large number of glass elements in a super-zoom, there’s more chance of unwanted effects like flare and ghosting.
Identifying lenses
The primary way of distinguishing between different lenses isn’t by model name or number, but by focal length and maximum aperture. Beyond that they often have various prefixes and suffixes indicating their relative quality and features.
You should bear in mind that lens names are very precise, and some are so similar it’s easy to become confused. For example, Canon until recently had two different 70-300mm zoom lenses. One was called the 70-300mm f/4.5-5.6 IS USM; the other the 70-300mm f/4.5-5.6 DO IS USM. The DO version Feature Table - Digital SLRS
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| All the specs and all the info you need on every camera tested |