Canon EOS-20D review

Canon's EOS-20D is an 8.2 megapixel semi-professional digital SLR and the successor to last year's EOS-10D.

It costs £1269 for the body alone, or another £80 bundled with Canon's 18-55mm EF-S lens, providing a budget 3x zoom option. While a passing glance could mistake the 20D for little more than a 10D with two extra megapixels, Canon has made a number of key improvements.

But first the sensor: a new 8.2 megapixel CMOS that's capable of delivering 23.4MB (uncompressed) images with 3504 x 2336 pixels and enough detail to be reproduced at 10 x 8in at 300dpi. Like other digital SLRs at this price range, the sensor is physically smaller than a frame of 35mm film, resulting in an effective multiplication of all lens focal lengths. In the case of the 20D, it's 1.6 times, so the 18-55mm EF-S lens effectively performs like a 29-88mm zoom.

Following the budget EOS-300D, the 20D becomes the second Canon digital SLR that can use the company's EF-S lenses. EF-S lenses are designed for digital SLRs with sensors smaller than a 35mm frame and so can be potentially smaller, lighter and cheaper than lenses optically corrected for a full-frame camera.

Canon's first EF-S lens was the 18-55mm f3.5~5.6, popularly bundled with the budget 300D and now optionally available in a 20D kit. It's extremely light and performs surprisingly well given its price. With the launch of the 20D, Canon has introduced two additional EF-S lenses - the 10-22mm f3.5~4.5 and the 17-85mm f4.5~5.6 with image stabilisation. The 20D is also compatible with Canon's wide range of existing EF lenses.

The 20D is fitted with a Compact Flash slot, which can accommodate MicroDrives along with cards greater than 2GB in capacity. As with all digital SLRs, though, you'll need to supply your own card. Images can be recorded as Jpegs or 12-bit Raw files and in a neat improvement over the 10D, Raw files can now be optionally accompanied by matching Jpegs of any resolution. Raw files and best-quality Jpegs measure around 7MB and 3MB respectively.

There's auto, program, manual, shutter and aperture priority modes, as well as five scene presets. The fastest shutter speed of 1/8000 is twice as quick as that of the 10D, and exposures down to 30 seconds or Bulb are available. Sensitivity ranges from 100-1600 ISO with an extended 3200 ISO option.

Both the buffer and data speeds have been increased in the 20D, delivering improved burst performance: the 20D can fire off 23 Jpegs at 5fps compared with the 10D's nine frames at 3.3fps. The new nine-point autofocus system is also much faster than that of its predecessor.

The improvements aren't just internal, either. Put the 20D next to the 10D and you'll see Canon has shaved off several millimetres and over 100g in weight. Indeed, its measurements are closer to the 300D, despite a considerably tougher magnesium-alloy shell.

The USB interface now supports USB 2 transfers, and the built-in flash pops up higher to reduce potential shadows cast by lens barrels. Like the 10D, there's also a flash hotshoe and a PC sync plug for studio lighting.

In use, the 20D handles very much like a much more expensive professional camera. The startup time is virtually instantaneous compared with the fairly sluggish two seconds of the 10D, and the faster focus and burst modes make serious sports, wildlife and fashion photography more viable.

With a sensor measuring the same size as the 6 megapixel 10D and 300D, Canon has clearly had to shrink the light-sensitive elements in order to squeeze in an extra two million. Normally this would lead to higher electronic noise levels, but improvements in sensor micro-lenses and processing have eliminated any concerns. In our tests, the 20D's noise levels matched (and even beat) the 10D and 300D, while its additional megapixels resolved measurably greater detail.