Despite the availability of a variety of DSLR manufacturers, the Canon versus Nikon debate is still going strong. Since the days of 35mm film, the two manufacturers have been close competitors. Traditionally, things seem to see-saw between the two, with each manufacturer becoming stronger for a while, before fading away to the other.
If you're not tied into a system, the choice of cameras can seem bewildering.
Which is the better buy? I'll take a look at the key points on each camera to help you make a more informed decision.
Resolution, Body and Controls
Canon's T3i has 18MP of resolution compared to Nikon's 16.2MP. It's unlikely, though, that you'll notice much difference in real world terms.
Both cameras weigh almost the same, with the Canon weighing just 0.35 ounces (10g) more. They're both sturdy little cameras, and they feel substantial. The Canon's hand grip is perhaps marginally easier to use, but both cameras have articulated LCD screens.
When it comes to controls and ease of use, I feel that the Canon is still yards ahead of the Nikon. The T3i has a four-way controller (which is a little on the small side), giving access to white balance, focus, drive modes, and picture styles. There's also a dedicated button for ISO, something which the Nikon D5100 is lacking. Existing Nikon users will also be confused by the re-design of control layout on the D5100 due to the articulated LCD screen.
The only place where the Canon falls down on controls is in the inexplicable change of functions of the 4-way controller once the camera is in Live View or Movie Mode. In these modes, the controller only allows for moving the AF-point around its nine points. This is confusing, to say the least!
Autofocus and AF Points
Both cameras have solid and reliable autofocus, although the Nikon's speed is reliant on whatever lens you're using, as it has no in-body autofocus motor. However, the Nikon's AF points are part of a far more sophisticated system than the Canon's. The D5100 has 11 points to the T3i's nine. But it also has four different modes for using the AF points, whereas the Canon only has two.
While both cameras produce great images, the D5100 is just a little bit better in most respects. The Canon produces excellent images in both RAW and JPEG formats, and it copes very well at high ISOs, offering users the option to reduce noise to their own set trade-offs against image detail and quality. However, the T3i yet again has Canon's trademark problems in coping with artificial light when using auto white balance, as images are distinctly orange. The T3i is also more prone to chromatic aberration than the D5100.
The Nikon also produces excellent images in both RAW and JPEG, and it does an even better job of keeping the noise down at high ISOs. Best of all, it doesn't seem to share other DSLRs' tendencies to overexpose in high contrast situations. It also has better dynamic range and color depth than the Canon.
I personally find the layout and control system of the Nikon confusing and somewhat lacking in key areas. However, image quality is where it counts, so, if you're new to digital cameras, then the Nikon has the edge. Both cameras have their plus points though, and users are unlikely to be disappointed by either machine.