The Panasonic Lumix FZ1000 may look like an ordinary superzoom, but it's got premium written all over it. Bigger, bolder, brighter: this Lumix embodies a large 1-inch sensor and a 25-400mm f/2.8-4.0 equivalent lens. Like a premium seat on a flight, is it enough to make you never want to give standard a consideration ever again?

The concept of a premium superzoom isn't brand new. Sony announced its Cyber-shot RX10 last year, complete with a 28-200mm f/2.8 lens and a whopping £999 price tag. The Panasonic FZ1000 goes one better from a number of points of view: the lens is wider-angle and has a longer reach and the price, despite still being a considerable sum, is a more affordable £750.

READ: Sony Cyber-shot RX10 review

But the first thing we noticed about the Lumix FZ1000 is its physical size. If you want that big sensor and the improved quality this is supposed to bring then you're going to need to be ok with handling a fairly big camera. Positioned next to the Lumix GH4 compact system camera and the FZ1000 is actually the larger of the two. It's a big wedge of kit, especially as the lens extends through to that 400mm top-end equivalent.

READ: Panasonic Lumix GH4 review

That doesn't mean it's uncomfortable, though, and weighing approximately 800g it's not too much of a burden to carry around. In the hand everything fits well to the fingers with an DSLR-like familiarity. If anything the lack of a front thumbwheel felt like an absence - there's a rear one instead, though - and we would like the zoom to shift through the range a little bit quicker. But this was a pre-production sample we saw almost two months ahead of its release date so there's scope for things to change.

We went shooting with the camera around Lacock Abbey in Wiltshire and, luckily, managed to avoid the worst of the UK's spring rain showers. Having recently reviewed the Lumix GH4, it's great to see a lot of the premium features from that camera appear in the FZ1000. From the off it's clear the "premium" label isn't just a marketing exercise.

The 49-area autofocus system, for example, offers many of the same features, including full-area AF across the entire screen and pinpoint focus options. The DFD (depth from defocus) system is also able to snap subjects into focus at a greater pace than even the older FZ200 superzoom, while sensitivity to -4EV means focusing in low-light is no problem.

READ: Panasonic Lumix FZ200 review

We were shooting a rocking horse in a dark room at ISO 6400 with no issues, while the interior of the Abbey was also no problem. Despite fast focus we did find some moving subjects, such as rotating placards in a tree, were a little tricky for the system to attain focus. At a fixed distance, however, everything snapped into focus double fast.

If you want an extra bit of focus control then the FZ1000 also has a lens ring that can be used for either manual focus or to adjust zoom - there's a switch to the side of the lens barrel to toggle between controls. We found using the standard zoom toggle around the shutter to zoom was our preferred method of use, leaving the ring set for manual focus to fine tune with focus peaking and focus assist aiding with accuracy.

As a fully featured camera there's a built-in viewfinder and tilt-angle LCD as part of the package, both of which deliver good results. The 0.7x magnification OLED viewfinder is large and delivers a 2,359k-dot resolution - but we found moving it fast was a little disorientating. An eye-level sensor means automatic viewfinder activation, or press the camera's Fn5 button to manually toggle between screen and finder as being always on.

A strong reason to consider buying the FZ1000 is, of course, its large 1-inch 20.1-megapixel sensor. This sits the Panasonic in contention with its Sony rival in terms of resolution, but its the lens difference that's worth taking a good look at. Despite a longer reach from its lens, the Panasonic's maximum aperture at its 200mm equivalent isn't quite as impressive as the Sony's constant f/2.8 offering - instead dropping to f/4.0 well before its maximum 400mm equivalent is reached. That puts the Panasonic a whole f/stop behind compared to the Sony.

But if you want a superzoom to provide considerable zoom - and the clue is in the name really - then the availability of a 400mm equivalent will be a huge lure to the FZ1000. It's not as far-reaching as some smaller sensor superzoom models, but that's a given if the large sensor is a must. Any more zoom and not only would the price rise, so would the physical size of the camera. And it's already big enough as it is.

And the large sensor certainly makes sense. Although we're not permitted to publish full-size image samples from the pre-production model (and there were apparent processing issues from ISO 12,800 and above) we've been impressed with what we've seen.

Blurred backgrounds from that bright aperture look quality and there's plenty of detail in the low ISO shots. Even shooting further up sensitivity range saw quality results through to four-figure ISO settings, but until we've seen a final production sample of the camera we can't critically comment on the results.

Video capture is another considerable area, with the FZ1000 being the first compact camera to offer 4K capture. Ok, so it's not a "compact" kind of compact, but at 30fps that's a future-proof feature right there. It's also possible to extract 8MP stills from the 4K capture, so if the 12fps burst mode (at 20MP) isn't quite enough for you then the 4K option means that 25/30fps is available.

Even 1080p can be captured at 100fps for slow-motion playback and there's zebra patterning, focus peaking, hue adjustment and a cine-like gamma option to up the ante when it comes to moving image capture.

Elsewhere there's a 1/4000th sec mechanical shutter or a silent electronic shutter can be used at up to 1/16,000th sec. Ideal for freezing action but, and as we discovered, the silent nature of shooting - no shutter, no beeps - helps assist with being less conspicuous. Great.

After a couple of hours use the DMW-BLC12 battery had drained by an apparent third. How many shots per charge will be possible we'll just have to wait and see when we get the finished FZ1000 in our hands for review. And we're quite excited by that prospect: as a DSLR alternative superzoom there's a whole lot on offer here and the accessible price point more than gives the Sony RX10 a run for its money.

The Panasonic Lumix FZ1000 will be available from mid July, priced £750. Pre-orders will received an additional battery and carry case free of charge.