It's a curious time in the world of cameras right now, with boundaries ever-blurring, but new technologies incremental rather than revolutionary. The arrival of the Nikon D5500, which is the company's first ever touchscreen DSLR, looks to fend off the competition and, but of course, the advance of compact system cameras in one fell swoop.

The D5500 may well be Nikon's first touchscreen DSLR, but it's not the first; it's actually a bit behind on that front. The Canon EOS 700D, released in the second half of 2013, had a similar touchscreen flavoured focus. And compact system cameras' lives often depend on such a touch-focused feature, from Panasonic, to Olympus, and Samsung to Fujifilm. Even Nikon's own 1-series is all about touch and speed.

So is the Nikon D5500 too late to the game in a field where there are cheaper, albeit often less pixel-packed, alternatives?

As the incremental upgrade to the previous D5300 model, there's actually a lot more going on in the D5500 than initially meets the eye. Promoted in the USA as "the world's smallest, lightest and slimmest" DSLR camera, it could only be considered so in the far away land of Caveatville.

Indeed the Canon 100D, or SL1 as it's known Stateside, is smaller, lighter, and slimmer - but then it doesn't have a vari-angle LCD screen. There's the crucial difference for the Nikon D5500.

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We saw and used the D5500 next to its older brother, the D5300, which made for a great direct comparison. The footprint of the two cameras is critically different (less obvious when facing them front-on), the D5500 offering a deeper, more considerable grip that, while subtle, is a big step forward on the ergonomic scale. Especially considering the body is smaller in the newest generation.

The kit lens, too, is a collapsible 18-55mm, with the interest in keeping the size down compared to the older, fatter version. Also a sensible move.

But smaller size isn't always beneficial to all areas: the 0.82x magnification 95 per cent field-of-view optical viewfinder means an ever so slightly smaller image than the 0.85x mag of the D5300's finder. But could we notice the difference between the two? No. It's small scale build that takes precedence as that's how Nikon is staying relevant and what the consumer wants.

And there's still a lot to be said for an optical viewfinder compared to the electronic versions that some compact system cameras feature. The D5500's finder view is clear, while the 39-area autofocus system clearly presents its focus points, with the active focus point, or the point that has acquired focus, illuminated in red.

The viewfinder gains a fun new feature from the D5500's touchscreen too. Within the menus is an "Assign touch Fn" option, which leaves the screen active when the viewfinder is in use. With the screen protruding to the side of the camera thanks to its vari-angle bracket it's possible to drag a finger around it, eye firmly stuck to the viewfinder, to adjust the active focus point. It's really responsive and the adjustment clear direct to the eye. Alternatively you can adjust ISO, AF-area mode, and many other options this way instead.

But the main purpose of the touchscreen implementation is for improved focus during live view. As the D5500 is a DSLR its through-the-viewfinder and screen-based autofocus systems work in different ways; the screen-based contrast-detection solution being a little slower than the viewfinder-based phase-detection solution.

When live view is activated by flicking the Lv switch, which is collared around the mode dial atop the camera, it shows a direct readout from what the sensor is seeing to the screen. That's great for more accurate "what you see is what you get" colour, while the ability to shift focus quickly and easily, or even fire the shutter the second focus is acquired, is a clear advantage. It's about time such a feature made its way into a Nikon DSLR.

However, the live view autofocus still isn't blindingly fast. Nikon claims a 20 per cent bump in speed compared to the earlier D5300 model, but put to the test side by side and we didn't see a drastic difference between the two cameras. Yes the D5500 is faster, but both models had to hunt to acquire focus in the mixed lighting room we were in. It's here that DSLR cameras just aren't up to scratch compared to their compact system camera cousins, which is something Nikon is obviously trying to close in on.

Continuous autofocus using the viewfinder, on the other hand, is far superior in the D5500 compared to a compact system camera offering. If you're content using a viewfinder for the majority of work, happy to take benefit from the camera's improved autofocus for things like video work, and intend to shoot moving subjects then the D5500 makes a good overall case.

As we alluded to in the opening gambit of this preview, camera technology does continue to push forward, but not in leaps and bounds. On the imaging front the D5500 adopts the very same 24-megapixel APS-C sensor (known as "DX" in Nikon speak) as found in the D5300. Like before there's no optical low-pass filter, for critical sharpness, with the only push in the new models being the latest Expeed 4 image processing engine taking command.

Now that ought to mean better images than before, but based on the demo snaps we took on the pre-production D5500 it's hard to be critical at this moment in time. We will need to wait until 5 February before the camera hits the shelves before we can pass judgement. But our gut feeling is that even if the quality isn't a giant leap forward, it's built from a solid foundation that will more than deliver the goods.

What the latest processing engine also brings is an extra crank of speed. The 5fps burst mode will whirr off five shots per second even with the highest quality raw and JPEG options selected. Again, a small bump compared to before, as the D5300 could also shoot at 5fps, albeit not with 14-bit raw file quality selected.

There's no GPS (global positioning satellite) on board this camera for geo-tagging images, it is available via the GP-1 or GP-1A accessories (sold separately). Wi-Fi, on the other hand, is built-in for the ability to share images on the go via a synched smart device app - although without the software seeing a significant update at present, there are improvements that could happen in this department too.

With some clever work going on behind the scenes to squeeze the D5500 into a smaller footprint than its predecessor, we find it a successful, albeit subtle, incremental step forward to the series. In context to the wider DSLR world, however, it's not so clear cut: with the more affordable Canon EOS 700D already available and some compact system cameras offering better live view autofocus, it's not going to be the game-changing DSLR to seal the deal for all prospective buyers.

That said, we like the advances that touchscreen capabilities bring and expect great image quality to boot - particularly when aligned with the huge array of Nikon AF-S lenses available.