Ahead of the unveiling of the Pentax K-3 we had the chance to test out a pre-production model of this top-spec DSLR. And we like what we've seen from the top-spec camera's features.

Despite various rumours Pentax has not pushed into the full-frame DSLR territory and, who knows, perhaps that will never happen. But with Ricoh now behind the company - Pentax Ricoh Imaging Company to give the full title, as shown by the Pentax logo on the front of the K-3 and the Ricoh logo on the rear - there's more scope than before, and the K-3 is the sum of Pentax's progression thus far.

Yes, the K-3 still runs with the APS-C sensor size, but it's the highest resolution one we've yet seen, pushing out to a 24-megapixel resolution. If that sounds similar to the Sony Alpha A77 or A65 then it's for good reason: it's the same base sensor. But Pentax has a certain way with its image processing and, typically, we've found the company to get the utmost out of raw hardware.

READ: Sony Alpha A77 review

We hold high hopes for the K-3. However, so far we've only been able to snap a few images around a room and are not able to publish them. But from what we saw on the camera's rear 3.2-inch it's all looking good.

There's another reason for that: the K-3 has ditched the optical low pass filter present in many DSLR cameras in order to produce sharper images. But when it comes to tight and repetitive patterns, that ups the risk of moiré.

Or does it? Pentax has introduced a hardware option called "advanced anti-moire" that uses the sensor's ability to move - it has an auto-level correction for straight horizons as well as sensor-based image stabilisation - by vibrating a minute amount so that light will fall into more than one sensor node, thus delivering a similar softening effect. Kind of crazy, kind of cool.

Elsewhere there are features that continue to bolster the K-series heritage. Pentax has broken out of the 11-point autofocus system and introduces the brand new 27-point SAFOX 11 system. Its arrangement is similar to that found in the K-5 model - it's a central rectangular arrangement with two line points to the side - but there are now more points for improved tracking AF and a greater detail when it comes to autofocus. Of the full set all 25 of the central points are cross-type sensors for heightened sensitivity.

READ: Pentax K-5 review

In the room where we got to see the K-3 the light wasn't particularly good - the sample shots of the product on this page were shot at around ISO 1600-3200 at f/4 to give a rough idea of the artificial light - but we found the system chomped through various subjects. The system can be set up in single (AFS), continuous (AFC) and auto (AFA, a hybrid of the two that senses subject movement before kicking in continuous autofocus) and the rear of the camera includes a function button to quick adjust the selected autofocus point using the rear d-pad. It enlarges the 27-point system on the rear of the camera's screen which makes it easier to visualise.

In the viewfinder itself the points illuminate red to make clear where focus has been attained. It's bright and clear, even if there is some dotted light fall off per point - nothing that affects the results though. It all works quickly, but it's not silent. The 40mm f/2.8 pancake lens that we were using made a fair racket to the ears. Not ideal.

Other lenses we're yet to test out, so it may be a confined issue. 

The K-3's optical viewfinder is also larger than that of the K-5. The 0.95x magnification gives an amplified size in preview. It rests comfortably to the eye and we're big fans of the 100 per cent field of view too. Nothing amiss here.

However, that viewfinder does make the top of the camera that much boxier and larger. It's not a criticism, as such, more an observation: the K-3 has that "Pentax look"; it's not trying to be anything other than what it is. Its style is more a focus of function, and the various one-touch function buttons help see to that. It's eminently usable, even if the classic Pentax menu can feel like a bit of a slog to dig through. But that's reserved for only the fussier mode adjustments.

One of the other top specs is the K-3's stainless steel chassis with 92-point weather-sealed exterior. We didn't chuck a glass of water over the camera, but we'll take Pentax's word for this based on use with previous K-series models. And there are visual signs of such sealing on the exterior: the inclusion of both a mic port and a headphones jack - useful for video capture - are covered neatly into the body design. The rubber seals felt reassuringly firm to remove, and the likes of the dual SD card slots and USB 3.0 output port - the first time we've seen such things in a Pentax and, indeed, the first time a DSLR has touted USB 3 - were well tucked away yet easy to access.

Finishing off the specification is the ability to shoot up to 8.3 frames per second; Flu Card is available for wireless transmission and app-based control; metering is handled by a new 86,000-pixel RGB sensor; the new Prime III image processing engine can cater for shots up to ISO 51,200; and there are various accessories such as the battery grip, as shown in our hands-on gallery pictures.

Whew, that's a lot of chatter. But then there's a lot to talk about with what stacks up to be Pentax's most serious DSLR to date. It might not be full-frame, but it has fully captured our attention from an APS-C perspective. Looks good to us, but can it hold off the likes of the established Canon EOS 70D?

READ: Canon EOS 70D

The Pentax K-3 will be available in black or limited-edition silver, priced £1,100 body only. Release date is yet to be finalised, but we'll see it on the shelves in the non-too-distant future.