To do it, the 550D has an 18 Megapixel APS-C sensor with 1080p HD video, which is enough to leave some other manufacturers quaking. But who actually needs that many pixels?
The 550D has relatively compact frame which, although it's made entirely from plastic, has a nice finish that's easy to hold. The handle might seem a little stingy if you've got big hands, but it's covered in rubber so the grip is good. Canon has opted for a fairly traditional set of controls and you'll find all of the buttons that you're used to: an ISO button, a scrollwheel and directional arrows to give easy access to white balancing, autofocus and the different image modes. Anybody that holds the viewfinder to their left eye will likely find the exposure correction button a little too close to their nose for comfort.
A 'Q' (for Quick Menu) button allows you to adjust the main settings like the quality, automatic brightness correction and exposure meter directly on the screen. The graphical interface is as easy to use as ever, with clear menus that are sensibly organised into tabbed sections. All that's missing is a contextual help system to help beginners find their way, which is something that all of Canon's main competitors offer.
The LCD screen itself is absolutely excellent, and has a new 3:2 aspect ratio that sits better with the format of the photos that this camera produces. Measuring 3'', it has room for 1 040 000 pixels. The viewing angles are very good, but the anti-glare treatment isn't very fictive, especially in bright sunlight. A pair of sensors just below the viewfinder turn the display off when the camera is pressed up to your face. The viewfinder itself is comfortable, with a good view, despite the 0.87x magnification, which is a long way behind the 550D's main rivals the Nikon D90 (0.94x) or Pentax K-7 (0.92x).
Pas de problème de ce côté, le 550D affiche de belles performances malgré une définition en augmentation. La mise sous tension est quasiment instantanée et le mode rafale atteint les 3,7 i/s annoncées. En pleine lumière, l'autofocus s'avère très réactif et dispose de 9 collimateurs pour couvrir une bonne partie du centre de la visée. En basse lumière, le système AF devient plus hésitant et manque parfois de précision (nous avons noté encore quelques mises au point hasardeuses). En mode visée directe, le système autofocus par détection de contraste reste toujours assez lent, même si Canon semble avoir optimisé la recherche du point. Ce mode est très efficace pour une nature morte par exemple, mais perd de son intérêt pour les autres situations.
With an 18 Megapixel APS-C sensor, we could have expected the worst ... but the 550D actually did very well. This is a digital SLR that can cope with electronic noise right up to 1600 ISO, and you won't hesitate before reaching for the ISO button to skip up to 3200 ISO or 6400 ISO. What grain there is isn't coloured and has a rather random structure.
It's best to have good quality lenses to make the most of the capabilities of such a powerful sensor. We still tried it with the new 18-135 mm f/3.5-5.6 IS and the results were pretty good. We noticed some purple fringing creeping into areas with a lot of contrast, but our test photos generally had a lot of detail. The exposure meter is pretty reliable, and by default, the colours are rather warm.
The 550D's last main strength is its excellent video mode (see inset) which is a very welcome addition to the camera's spec. The autofocus might not be up to it, but if there isn't too much movement, the 550D is a great camcorder that allows more than enough room to play with depth of field.