Review: Sony RX10 III

Introduction and features

The Sony RX10 III was announced in March this year, less than a year after the RX10 II which, according to Sony, the new camera doesn't replace. The most noticeable difference is the inclusion of a variable aperture (f/2.4-4) mega zoom lens, with a reach of 600mm (25x optical and 100x digital zoom), and with this comes a substantial increase in size and weight.

Like the Mk II, the RX10 III is aimed at the serious enthusiast end of the market – photographers looking for ultimate image quality and telephoto reach in a bridge-style package.

The RX10 III has the same 20.1 million pixel 1-inch stacked Exmor CMOS sensor, and offers the same excellent 4K video functionality, as the Mk II. In fact most features and functions are identical, and the main talking point is the large and impressive Zeiss 24-600mm lens. Only the Canon G3 X has the same reach, if we compare other bridge cameras with 1-inch sensors, with the much older Panasonic FZ1000 only going to 400mm.

The variable aperture of f/2.4-4 still makes this a pretty fast lens, certainly compared to the competition, and it boasts hugely impressive minimum focusing distances of 3cm at the wide end and 72cm at the long end.

As with other Sony compact and bridge cameras, a large range of shooting options and photo modes are included, with 3:2, 4:3, 16:9 and 1:1 formats for both raw and JPEG images. Maximum resolution is 5472 x 3648 pixels in its native 3:2 format. Sensitivity ranges from ISO100-12,800, expandable to ISO64-25,600.

Single shot autofocus (AFS), continuous (AFC), direct manual focus (DMF) and full manual focus (MF) are available, with Sony's very effective focus magnification and focus peaking options making the latter easy to use.

The EVF and tilting rear LCD are both high quality; the latter isn't a touchscreen, but unless you're using the camera on a tripod a touchscreen wouldn't be particularly practical given the size and weight of the camera.

There's no getting around the bulk of the Sony RX10 III. It's very well made and comfortable in the hand, but I suspect many more casual users will be deterred by its size (and price) and, if they want such long telephoto reach, may opt instead for the Canon G3 X or possibly the Panasonic FZ330/300, which has a smaller sensor but also offers 4K shooting, and impressed us last year. The Canon suffers from a slower lens and no included EVF by comparison, but the FZ330/300 does benefit from a constant f/2.8 aperture, albeit with a much smaller sensor.

However, if you want the ultimate image quality in a bridge camera, it's hard to look beyond the class-leading performance of the RX10 III's Zeiss Vario-Sonnar T* lens, and I'm sure enthusiasts looking for more reach and a highly specified camera will be attracted to this. Whether they'll be prepared to pay the £1,250 ($1,500, AU£2,150) price tag is another matter. That price is likely to fall post-launch, but at the moment it's around double the cost of both the G3 X and the FZ1000 (the FZ330/300 is cheaper again). That said the RX10 III is in a league of its own in some respects, so it's likely to find a market, albeit a niche one.

Build quality and handling

The first thing I noticed when I took the Sony RX10 III out of its box was just how large and weighty it is compared to other bridge cameras I've used. At a little over a kilo in weight (1050g or 2.3lbs with battery and SD card) it feels more DSLR like in-hand. It measures 132.5 x 94.0 x 127.4mm (5.25 x 3.75 x 5.12 inches), and feels substantially larger and heavier than the likes of the Canon G3X. Much of this is down to the sizeable glass of the 24-600mm equivalent, 72mm diameter lens.

Although plastic-feeling, the build is reassuringly solid and its generous, protruding-front grip and rounded body style means you're able to grip the camera securely and comfortably. Those with small hands may find the grip a little too large, but it feels in proportion to the size of the camera. I found the ergonomics very good, with buttons and dials falling in the right place for my hands.

The on/off switch is toggle-style, and is incorporated into the shutter button on top of the front grip; it's easy to access and clicks reassuringly. A lever to the front of this allows you to zoom the lens. The shutter button is also threaded, meaning you can use an old-style cable release. The RX10 III powers up pretty quickly, although there's inevitably a short delay while the lens extends to its start-up position of 24mm.

The mode dial (left) and exposure compensation dial (right) both have a textured side and just the right amount of resistance, making them easy to adjust precisely. Two customizable function buttons, an LCD light and the pop-up flash button are also included on the right, and behind these is a small LCD panel that displays key settings. The small but solidly built pop-up flash and hotshoe complete the top plate layout.

An aperture ring is included to the rear of the lens, and can be de-clicked for video use. There are also two textured rings for zoom and focusing. I found it easier to zoom in small increments using the lens ring rather than the lever on the front grip. I found the focusing ring responsive and easy to use, with a conveniently located focus hold button to the left of the lens. A focus mode switch is included on the bottom left of the camera body; I found it slightly fiddly, but quick access to this feature is welcome.

Much of the rear of the RX10 III is taken up by the impressive 1,228,800 dot, tilting 3-inch LCD screen. The XGA OLED electronic viewfinder is excellent and boasts a 2,359,296 dot resolution. It's responsive, clear and bright, and works well with glasses. It has 0.7x magnification, an eye sensor to allow automatic switching between EVF and LCD, and a generous diopter adjustment. A lens hood is included, as well as a pinch-style lens cap.

Menu and movie buttons sit either side of the EVF. The rear control dial and control wheel operate smoothly and are easily accessed, enabling you to select and adjust various menu items and settings. The control wheel and center button also enable you to change the placement and size of the focus area when using flexible spot AF. AE lock, quick function, playback and delete buttons complete the line-up; the latter can also be used as a third custom function button.

Performance

Based on my experience with the Mk II version of the camera I was expecting the new 24-600mm lens on the Sony RX10 III to impress, and I wasn't disappointed. The lens performs extremely well throughout its zoom range; details are perhaps not quite as crisp as from the Mk II's lens, but given the far greater reach of this lens that's not surprising.

At most focal lengths the lens is remarkably sharp wide open. At its wider end I did notice softness at the far left side of the frame, suggesting possible decentering in my review camera, as the right side was tack-sharp. However, at telephoto focal lengths, the image is impressively detailed across the frame, right up to 600mm.

Sharpness increases marginally when stopping down slightly, but there's very little in it. Diffraction becomes more noticeable by f/11, although with a little more sharpening applied details are still very good. I would avoid going much above this if possible – by f/16 there's a noticeable fall-off in quality, as you'd expect.

Click here for the full-resolution image

Click here for the full-resolution image

Click here for the full-resolution image

Out of focus areas are rendered pleasingly, although f/2.4 is only available up until 35mm, with f/4 the widest aperture available above 100mm. This does mean that isolating subjects from their background can be a challenge at times, but the RX10 III still beats most of the competition in this respect. Distortion and chromatic aberration are both very well controlled throughout the range; I struggled to notice any examples of either, after photographing a range of subjects in varied conditions.

The lens is able to resolve both close and distant details, and its impressively close focusing distances of 3cm at the wide end and 72cm at the long end make it extremely versatile. Most potential purchasers of this camera are likely to shoot primarily in raw, but I was also impressed by the quality of the RX10 III's JPEGs. Colours are punchy and pleasing, with plenty of options for customization, and resolution and dynamic range are both very good.

Even at higher sensitivities I was impressed with the quality of the JPEG files. I found that using noise reduction at its lowest setting gave a good compromise between detail and noise, with files very clean and detailed up to ISO1600; the raw files do have more detail but the difference is surprisingly small. Above ISO1600, JPEG quality is still remarkably good, with very manageable noise levels, and I'd have no hesitation making A3 prints from files at ISO6400. Above this the files are certainly usable, but I wouldn't want to be making large prints.

Click here for the full-resolution image

Click here for the full-resolution image

Click here for the full-resolution image

Metering is accurate, and I was impressed with the dynamic range of the sensor, for both raw files and JPEGs, even without utilizing any of the HDR options. Auto white balance (AWB) is very accurate in sunny conditions, but tends to be a little on the cool side in shade, with a slight magenta bias; in such conditions selecting Shady gives a pleasing image, if very slightly on the warm side.

Autofocus is a bit of a mixed bag with the RX10 III. At wider focal lengths the AF is pretty snappy, working well for both still and moving subjects. At the longer end of its range, however, AF is really very slow, even with still subjects; it's accurate, once it's found its target, but the lens is prone to hunting.

Not surprisingly, this is exacerbated if you're trying to track a fast-moving subject at longer distances: my usual test, trying to focus on my dog as it ran towards me, was definitely a step too far for the RX10 III. For closer and slower-moving subjects I found I could get good results using centre lock tracking and the slow burst rate. The lack of blackout during continuous shooting is a definite bonus, and makes it far easier to follow your subject.

Click here for the full-resolution image

Click here for the full-resolution image

Click here for the full-resolution image

Sony's SteadyShot image stabilization is very effective and, with Auto ISO enabling you to set a minimum shutter speed, you can customize the settings to ensure camera shake shouldn't be an issue. It's a big camera, though, and a long lens, particularly when extended, so I found a minimum setting of 1/125 sec was a safe option at longer focal lengths; at the wider end 1/25 sec was readily achievable.

Although the RX10 III is suited more to enthusiasts, Sony has included a wide range of scene modes, creative styes and picture effects, which are fun to use and will no doubt be welcomed by some users. At the opposite end of the scale it's good to see options such the ability to use the self-timer in conjunction with bracketing, as well as many other features found on Sony's higher-end system cameras.

Video enthusiasts won't be disappointed with an excellent range of filming options, with 4K and HD modes and the ability to extract 8MP stills from 4K movies. The High Frame Rate (HFR) feature is a great option, enabling you to create slow-motion videos; and I was also very impressed with the camera's ability to handle mixed and contrasty light when shooting movies.

Lab tests: Dynamic range

We chose three rival cameras for the Sony RX10 III to see how it measured up in our lab tests: the Sony RX10 II, the Canon G3 X and the Panasonic FZ1000.

We've carried out lab tests on the Sony RX10 III across its full ISO range for dynamic range and noise (including signal to noise ratio). We test the JPEGs shot by the camera, but we also check the performance with raw files. Most enthusiasts and pros prefer to shoot raw, and the results can often be quite different. We were unable to record accurate resolution results for the RX10 III – we hope to restest the camera at a later date.

Dynamic range is a measure of the range of tones the sensor can capture. Cameras with low dynamic range will often show 'blown' highlights or blocked-in shadows. This test is carried out in controlled conditions using DxO hardware and analysis tools.

Read: Noise and dynamic range results explained

Dynamic range is measured in exposure values (EV). The higher the number the wider the range of brightness levels the camera can capture. This falls off with increasing ISO settings because the camera is having to amplify a weaker signal. Raw files capture a higher dynamic range because the image data is unprocessed.

Sony RX10 III dynamic range charts

JPEG dynamic range analysis: JPEG files show broadly similar results across the group at lower sensitivities, with the RX10 III, again surprisingly, faring a little less well than the competition at higher sensitivities.

Raw (converted to TIFF) dynamic range analysis: Surprisingly, the lab results show the RX10 III scoring less well than both the G3 X and FZ1000 at almost all sensitivities. Comparing results from out in the field, however, the RX10 III more than held its own.

Lab tests: Signal to noise ratio

This is a test of the camera's noise levels. The higher the signal to noise ratio, the greater the difference in strength between the real image data and random background noise, so the 'cleaner' the image will look. The higher the signal to noise ratio, the better.

Sony RX10 III signal to noise ratio charts

JPEG signal to noise ratio analysis: Interestingly, the RX10 III shows quite an improvement over the Mk II. Scores at higher sensitivities are particularly impressive, bettering the G3 X and matching the FZ1000; the FZ1000 leads the way for lower sensitivities, however.

Raw (converted to TIFF) signal to noise ratio analysis: The RX10 III lags behind both the Canon G3 X and Panasonic FZ1000 at lower sensitivities. At ISO3200 and above it betters the G3 X, but scores significantly less well than the FZ1000.

Verdict

The Sony RX10 III is an extremely capable camera, offering a huge focal range and excellent image quality, and I found it intuitive and great fun to use.

As well as producing superb still images, video quality is truly impressive. The camera is packed with useful functions and features, and offers fun creative modes for those who like to experiment. As we've come to expect from Sony, dynamic range is really impressive, particularly when you consider this is only a 1-inch sensor. JPEG quality is excellent straight from the camera, while the raw files are great to work with for those who prefer to fine-tune images in post-processing.

The slow autofocus at its longer end is frustrating, and this isn't a camera I'd want to use for action photography. As a general shooting and travel camera, though, the RX10 III is hard to beat, as long as you don't mind its bulk.

For those already using a DSLR or system camera with several lenses, I suspect it might be a bit too large as a second camera. However, for those wanting a one-camera solution, with great functionality, versatility and image quality, the RX10 III should be high on their list.

The price is high, though, and this may deter some potential buyers. It will be interesting to see what replaces the Panasonic FZ1000 which, although now two years old, still offers great functionality and much better value for money, albeit with a shorter maximum reach of 400mm. Elsewhere the Canon G3X looks a smaller, cheaper and attractive alternative for those who don't mind forgoing an inbuilt EVF and 4K video.

We liked

The Sony RX10 III is a hugely versatile bridge camera, offering class-leading image quality and superb video functionality. JPEG files have very pleasing colour and are impressively detailed, even at higher sensitivities, while raw files offer that little bit extra malleability.

We disliked

Autofocus at longer focal lengths is very slow, even with static subjects, and continuous autofocus really struggles with fast-moving subjects. It's considerably larger, heavier and pricier than the competition.

Final verdict

The Sony RX10 III is thoroughly enjoyable to use in most situations, with a superb 24-600mm f/2.4-4 zoom lens and a bright and detailed electronic viewfinder. It's packed with features and functionality for both stills and video enthusiasts, and delivers class-leading stills and movie image quality.

It's let down somewhat by its autofocus, and some may be put off by its relatively large size and weight; however, as long as action photography isn't high on your list the RX10 III is hard to beat as an all-in-one and travel camera, albeit one that comes at a price.