In the increasingly popular digital SLR market, two companies reign supreme. Canon has the lion's share of the market, with Nikon hot on their tail. At the low end, Canon's EOS 400D has been a dominating presence and while Nikon's D40 competitor has made up some solid ground, in an area driven by megapixel counts, the 6 mega pixel Nikon hasn't quite been able to take first place.

Enter the D40x, an updated D40 with a 10 megapixel sensor, clearly designed to compete directly with the EOS 400D. It offers the same smooth, speedy operation as the D40 and packs in great image quality along with all the usual SLR features. While it is hard to be certain which model comes out on top as the competition is so close, you can be certain that the D40x is an excellent entry level SLR.

The most noticeable impact of the increased pixel count is in the image sharpness. As usual we ran our suite of Imatest tests as well as some subjective analysis on the shots. In the sharpness test, the D40x scored a massive 1896, which is ahead of both the EOS 400D and D40 by a reasonable margin. Our test shots reflected this, with stunningly clear edges and no visible fringing at all. The pictures definitely lived up to our expectations and are perhaps very slightly crisper than those produced by the competition.

In our chromatic aberration test the results were less impressive, but still far from average. Imatest gave the D40x a score of .94%, which is roughly comparable to competing models. There is evidence of some minor haloing in our test shots, but it is considerably better than the prominent red and blue haloing we noticed on the EOS 400D. This is a clear sign that the lens used on the D40x is of a much higher quality, which is a great sign as that is the main point companies cut costs on entry level SLRs.

As expected, the D40x's noise performance is flawless. It scored 0.38% in this test at ISO 100, which is in line with other entry level SLRs. Furthermore the noise scaled excellently with higher sensitivities. Our shots were perfectly usable all the way up until ISO 800, with a sharp jump in noise when using ISO 1600. Those that regularly like to shoot at ISO 400 or ISO 800 should find this model appealing.

Our final test is for colour, and the D40x performed well in this regard. Its score of 11 is a little lower than the D40 and EOS 400D, but the difference wasn't too noticeable in our shots. Colours are still deep and rich with nothing obviously oversaturated. Overall, we were pleased with the colour balance.

The other notable thing about the D40x is its speed of operation. Like the D40 before it, everything about this model is lightning quick. From the three frame per second burst mode (which runs constantly until the card fills up, assuming you are using a high speed memory card) to the absolutely instant power up time and the tiny 0.03 seconds of shutter lag, this is, simply put, one of the fastest cameras on the market. Even navigating the menu and changing settings causes no delay in your photography, as you can be back snapping pictures in an instant.

All the features you'd expect from an entry level SLR are present. The staple shutter, aperture and program priority modes along with full manual mode are on offer, but there are also a variety of scene modes for less experienced users. White balance can be dictated using presets or the manual mode, and there is an option to tweak each individual preset by a certain degree, to help tailor to specific situations. ISO sensitivities extend up to ISO 1600, although there is also an ISO HI setting for those extremely low light or fast paced situations (however we wouldn't recommend using it if you are at all adverse to image noise). The only slight area of disappointment is the focus points. Nikon only offers three focus points for their multipoint system, as opposed to the nine offered by most of the other 10 megapixel models. This may not be a big deal to all users, but some may find this a little limiting.

Everything is laid out in pretty much the same fashion as on the D40. Like most other manufacturers, Nikon has abandoned the second display in favour of showing all pertinent settings and data on the main screen. We think this is a good move, although the implementation is a little irritating as the screen powers down after a short period, and you constantly have to hit a button to bring everything back up.

There are two options for altering settings - you can either go through the main menu or use the on-screen display on the default screen. We found the later to be quite intuitive; just hitting the Info button opens access to all the major camera options, which is great for novice users. There is also a comprehensive in-camera help menu which will offer some much needed guidance to those who are a little daunted by the complex SLR functionality.

The design is also basically identical, which is not a bad thing in the slightest. The D40x sits very nicely in the hands and is very comfortable to use. It has the usual jutting right hand grip and rubberised surface which will be familiar to anyone who has used an SLR in the past. Despite being constructed mostly of plastic it feels sturdy and is more than strong enough to take on the road with you.