Sony Cyber-shot DSC-RX10 review

Sony has been churning out groundbreaking cameras at an astonishing rate over the last couple of years, but at first glance the RX10 just seems confusing. It looks like an ultra-zoom camera, but its 8.3x (24-200mm equivalent) zoom range is bettered by many compact cameras. It uses the same 20-megapixel sensor as the superb Sony RX100 II, but while its 1in size is significantly larger than the sensors in other bridge and compact cameras, it’s a good deal smaller than the APS-C and Micro Four Thirds sensors used in most compact system cameras (CSCs). That was perfectly forgivable in the slender RX100 II, but the RX10 is bulkier and heavier than most CSCs.

SONY RX10 LENS

The key to the RX10’s appeal is that its lens has a constant f/2.8 aperture throughout its zoom range. Compared to a typical SLR or CSC kit lens with an f/3.5 to f/5.6 aperture, that’s about 50 per cent brighter at the wide end and four times brighter at the telephoto end of the zoom range. Constant aperture lenses are available as expensive upgrades for SLRs and some CSCs, but never with a zoom range anywhere near 8.3x. The only comparable camera is the Panasonic FZ200 with its f/2.8 constant aperture throughout its enormous 24x (24-600mm) zoom range. The RX10’s 1in sensor is far bigger than the FZ200’s 1/2.3in sensor, though, which greatly enhances its low-light capabilities.

These aren’t the kinds of specifications that will attract casual users, so it makes sense that Sony has packaged this sensor and lens in a camera that’s aimed squarely at keen photographers. The magnesium alloy body looks suave and elegant, and it’s weather sealed too. The superbly designed handgrip makes the camera’s considerable 834g weight sit comfortably in the hand. The card slot is side-mounted for easy access when using a tripod, while the left flank is adorned with USB, HDMI, microphone and headphone sockets. Charging is in-camera rather than via an external charger, which prohibits using one battery while charging another.

The 3in LCD screen has a crisp 1.3-million dot resolution and tilts up by 90 and down by 45 degrees to enable shooting at awkward angles. The OLED electronic viewfinder is one of the best around, with a 2.4-million dot (1,024×768-pixel) resolution and a view that’s just as big as a full-frame SLR’s optical viewfinder. There’s also a passive LCD screen on the top plate for relaying settings, complete with an orange backlight.

SONY RX10 CONTROLS

The controls are just as impressive. There are lens rings for aperture and zoom. It takes quite a few twists to traverse the entire zoom range but we still prefer it to the zoom lever that’s also available. The zoom ring diverts to focus duties when manual focus is selected on the dedicated switch. With dials on top for exposure mode and exposure compensation, plus a command dial and a rear wheel, there’s no shortage of rotary controls. It’s less well endowed with buttons, with AE Lock being the only labelled photographic function. However, a Custom button on the top plate is sensibly assigned to ISO speed by default, and the left, right, down and centre buttons on the navigation pad can be assigned to any of 37 functions.

The centre button is assigned to an Eye AF function by default, and pressing it triggers the camera to focus on the subject’s eye. It’s a natural extension to face detection, and we hope it becomes just as ubiquitous. We’re also delighted to see that the flexible spot AF mode includes a choice of three area sizes – on previous Sony cameras we’ve found the fixed size to be too small at times.

There are more goodies tucked away inside the camera. A three-stop neutral density (ND) filter reduces incoming light by a factor of eight, facilitating slower shutter speeds for creative effect. It also compensates for the relatively slow 1/1,600s maximum shutter speed at f/2.8, although this halves to a more rapid 1/3,200s at f/8 and above.

Wi-Fi is built in, complete with NFC for easy connection to compatible Android devices. It supports wireless transfers and remote shooting with iOS and Android devices. The ability to use a tablet as a remote monitor while recording video is particularly welcome, but this is only possible in fully automatic recording mode – the camera’s exposure controls are disabled.

SONY RX10 VIDEO

The video mode is otherwise extremely well specified, with 1080-25p, 1080-50i and 1080-50p recording in AVCHD format at up to 28Mbit/s. Our test footage looked phenomenal, with exceptionally sharp, smooth fine details and that matched the best 1080p cameras we’ve seen, such as the Panasonic GH3. ISO 3200 clips were just as detailed and only displayed a light fizz of noise in darker parts of the frame.

There’s full control over exposure settings, with priority and manual modes and live adjustment while recording. There’s even a switch on the lens barrel to change the aperture ring from stepped to smooth – and silent – adjustment. The HDMI socket transmits a clean, uncompressed output for monitoring on and recording to external devices. The microphone input gets a significant boost by the inclusion of a headphone output, so you can actually hear what you’re recording.

There’s all the ports that videographers could want and expect

The autofocus responded smoothly and decisively while recording, but it’s disappointing that the selected autofocus area was ignored as soon as recording commenced. Face detection continued to work, though. For precise control over focus, it’s best to switch to manual control – the large lens ring, focus peaking display (which highlights sharply focused parts of the frame) and high-resolution viewfinder make this one of the easiest cameras to focus manually with.

Autofocus performed well for photos, too, and helped the camera to capture a frame every half a second in normal use. That’s significantly quicker than the RX100 II, which only managed 0.9 seconds between frames. Continuous performance was blisteringly fast, delivering 25 shots at 10fps before settling into a 2.8fps canter. It performed well for RAW capture, too, capturing 10 frames at 6.5fps, slowing to 1.6fps. The only disappointing result was for continuous shooting with updated autofocus between each shot, which trundled along at 1.3fps – the single drive mode gave better results.

SONY RX10 IMAGE QUALITY

The RX100 II gave some of the best photos we’ve ever seen from a compact camera, so it came as no surprise to see similar results here. Noise was virtually imperceptible at low ISO speeds, and the sharp lens and accomplished JPEG engine produced photos that could easily be mistaken for an SLR’s output. Processing RAW files in Adobe Lightroom 5 gave a further boost to the fidelity of fine details and wide-reaching control over colours, but this camera’s JPEG output is more than up to scratch.

Details here are razor sharp – not bad for a 20-megapixel sensor sat in front of a bright f/2.8 lens

Comparing JPEG and RAW output (processed in Lightroom 5) reveals that a little more precision is available in RAW files

The 24-200mm (equivalent) focal length range gave far greater flexibility to frame shots than most SLRs’ and CSCs’ kit lenses allow. Meanwhile, the constant f/2.8 aperture delivered a shallow depth of field for telephoto shots that helped subjects stand out from the background. Best of all, the constant aperture let us zoom in without the risk of rising noise levels. F/2.8 captures four times more light than f/5.6, and this advantage more than made up for the smaller sensor compared to rival cameras with Micro Four Thirds and APS-C sensors.

The extended zoom range is extremely useful for composing shots…

…but it’s the f/2.8 aperture that really makes the difference. There’s a fair amount of noise in this ISO 6400 shot, but rival cameras would have had to use much faster ISO speeds, or risk blurring the picture with slower shutter speeds

Direct comparisons with the Panasonic G6 at a 197mm (equivalent) focal length demonstrate how the RX10’s brighter lens is more significant than the G6’s bigger sensor. Both cameras are set to shutter priority, 1/200s, but the G6 is forced to use a much faster ISO speed to compensate for its darker aperture, and that pushes its noise levels up

The difference is even more pronounced indoors, even at a relatively modest 50mm (equivalent) focal length

With a lack of headline-grabbing specs and a price just shy of £1,000, it’s hard to imagine people queuing up to buy the RX10. However, on the simple issues of zoom range and image quality, we’re hard pressed to think of a more capable camera at this price. The Canon 700D and 18-135mm lens costs around £750, while the Panasonic G6 with 14-140mm lens costs around £650. All three cameras have broadly similar (35mm-equivalent) focal length ranges, and their sizes and weights aren’t wildly different. The RX10 trails slightly behind the 700D for image quality in wide-angle shots, but it maintains that quality as it zooms in in subdued light, whereas the others deteriorate significantly. Constant-aperture lenses are available for SLRs and CSCs but they’re limited to 3x and 4x zoom ranges and cost from around £500 to over £1,000.

Of course, SLRs and CSCs have the flexibility of being able to swap lenses for all sorts of specialist uses. Attach a cheap f/1.8 prime lens to an SLR and it’ll beat the RX10 hands down in low light, albeit without the luxury of a zoom. However, a bag full on lenses isn’t always practical when travelling, and it can get very expensive. For dependable image quality across a generous zoom range without the hassle of changing lenses, the RX10 is in a class of its own. The fact that it’s brimming with luxurious features makes that little bit easier to justify the high price.