The G3 X has been an open secret for some time and we've been featuring it for months on our camera rumors page – but now Canon has announced it officially. The headline feature is its 25x optical zoom, offering the equivalent of 24-600mm.
There are lots of compact travel zoom cameras like the Panasonic TZ70, say, that go even further, while top bridge cameras like the Canon SX60 HS and Nikon P900 offer 65x and 83x optical zooms respectively.
But the point about the G3 X is that it offers a big zoom range in conjunction with a much bigger (and hence better) sensor. Regular travel zooms and bridge cameras use titchy 1/2.3-inch sensors, and that restricts the kind of image quality they can produce, but the 1-inch sensor in the G3 X is four times larger. That means it should capture more detail, produce less noise and – potentially – offer increased dynamic range. It's not as big as the APS-C sensors in most digital SLRs and compact system cameras, but it's half way there.
This is the sensor used in the Canon PowerShot G7 X high-end compact, and we gave that camera 4.5 stars.
Lens is more
The key factor, of course, is going to be the quality of the lens. The 25x zoom range is not especially long on small-sensor cameras, but it's the first time we've seen one with this kind of zoom range on a camera with a 1-inch sensor. Even our favorite bridge camera, the mighty Panasonic FZ1000 (which also has a 1-inch sensor) can only manage a 16x zoom range.
That doesn't make the G3 X better straight away, though. For a start, the FZ1000 has a constant f/2.8 maximum aperture, where the G3 X lens has a variable f/2.8-5.6 lens. And where the FZ1000 has an electronic viewfinder built in, it's an optional extra on the G3 X – which is already pretty expensive.
Other key features
The G3 X is pitched at enthusiasts and offers full manual control and the ability to shoot raw files, as you'd expect from a camera in this class.
It has a dust and drip-proof body, and it can shoot continuously at 5.9 frames per second. The larger should mean it delivers good image quality in low light, too – it has a maximum ISO 0f 12,800. It has Wi-Fi and NFC for remote camera control via a smart device and quick and easy cable-free image transfer.
The G3 X is very adept at movies, too – in fact it reads more like the spec list for a high-end DSLR, not a compact camera. It can shoot full HD at frame rates from 24p to 60p, and it offers manual control of shutter speed, lens aperture and ISO in movie mode. It has a socket for an external mic, as you'd expect, but it also has a headphone socket for monitoring audio during recording. And the Canon's 5-axis image stabilization operates in movie mode too.
For less serious film makers there's a Short Clip Movie mode which captures movies of 4, 5 or 6 seconds in length, and there's a Story Highlights Mode which can automatically assemble stills and video clips into shareable movies.
The G3 X does not easily fit, however, into any existing camera category. It doesn't have the chunky profile of a typical bridge camera, but it measures a pretty substantial 123.3 x 76.5 x 105.3mm (4.9 x 3.0 x 4.1 inches) and weighs a hefty 733g (26 oz). It might look a little like a long-zoom compact travel camera, but its size (mainly the length of the lens) puts it well outside that category.
The Canon PowerShot G3 X goes on sale in mid-July and will cost £799.
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