The Sony RX10 III is, as the name denotes, the third in the line of RX cameras

Forbes Island, the incorrectly-named, cramped and awkwardly bobbing manmade structure in San Francisco’s harbor would seem like an odd place to test the new Sony RX10 III. The structure, built in the 1980’s, resembles an island (complete with lighthouse) but is, in fact, a barge of sorts, powered by a tugboat-strong engine and featuring a below-deck dining hall.

Sony brought a small group of the media to Forbes Island after a day of presentations and shooting at the San Francisco Zoo to get an unfettered view of the San Francisco skyline at sunset, and to photograph several models they had on the deck of the island.
The Sony RX10 III is, as the name denotes, the third in the line of RX cameras, but it does not replace the RX10 II, released last summer. While the camera features most of the shooting features of the RX10 II—excellent 4K shooting, a “stacked” CMOS sensor with excellent low-light capabilities and super-slow-motion video, the Mark III version gives the system a new lens with a 25x lens, equivalent to 24mm-600mm in a 35mm format.

Much like the Canon G3X, with which the RX10 III shares the same zoom range, the camera feels like an odd duck in a family of fixed-lens travel cameras, but ends up being much more than the sum of its parts. Unlike the Canon G3X, the RX10 III has a minimum aperture of f/4, where the G3X stops down to f/5.6—a doubling of available light at the long end of the zoom.
Long-zoom fixed lens cameras are an interesting proposition, needing by definition to be a jack-of-all-trades. The RX10 III is no exception, providing wide-to-long zoom ranges, 4K video capability that’s best in class as well as super-slow motion—it’s a lot for one camera to do.

With a price tag north of $1500, it’s interesting to think of the perfect customer for this camera. While I chuckled at the girth of the Canon G3X when I first looked at it, I reviewed it on a trip to Paris and it ended up being an excellent all-around camera, able to capture images on both the left and right banks of the Seine without having to walk across a bridge. I’m not sure, though, that I’d ever buy a super-zoom compact as my primary camera, so the market depends on people who feel differently, or who want to use a 1”-sensor camera as a secondary body.
The RX10 III captures video at incredibly high resolution, capturing nearly a 6K video stream with no pixel binning or line skipping (meaning every pixel on the sensor is used for the video, where most other systems skip some pixels and interpolate the data for faster processing) and it can create beautiful 4K video. Slow motion video can be captured up to 960fps, for some dramatically slow moments.

A quick note about slow-motion video—you’ll need to read the manual carefully to get it working. There is a combination of settings that the camera’s menu and dials needed in order to put the camera into slow motion, and the process is confounding. Be sure to figure it out before you head to your child’s ballet recital to capture a grand-jete.
For photographers, the camera offers an excellent image path with very fast processing times, albeit it in a package that’s far boxier and chunkier than Sony’s own A7 series and even more so than the svelte a6000 line. There’s a lot being packed into the RX10 III, which also makes it a bit more fragile than a camera like the A7—Sony mentioned the drop rating on the RX10 III is measured “in inches.”

When it comes to size, though, it wouldn’t be possible to create, say, an a6300 with the same zoom range using a single lens (or any single lens, really) so the RX10 III gives photographers with a need for a wide range of composition choices a good all-in-one solution.
The Sony menu system is a bit daunting for the new user, but very powerful once you start to know where settings are found. Programmable buttons gives the photographer a wide range of custom shooting setups. I still wish that Sony would use a touchscreen LCD in their cameras—even if only in the lower-end units—because it really expands what can be done without having to press little buttons and dials.

While the RX10 III sees the addition of a new top-deck LCD screen, which is very welcome, that lack of a front control dial seems glaring, until you realize that the camera has moved the main controls for focus, aperture and zoom to dials on the body of the lens. At first, having three dials is rather confusing but the hand soon moves to the right ring. There is also a zoom rocker switch under the shutter release button, and while the action is smooth, it’s noticeably slow to change focal lengths when shooting stills. It’s pretty clear that the slow-yet-smooth motor action is designed to create nice focus transitions in video, but it doesn’t do any favors for photographers looking to move quickly from wide angle to zoom.

Since the zoom is “fly by wire”, meaning that even the controlling lens dial is non-mechanical, twisting the zoom dial takes a while as well. It would be nice to be able to choose zoom speeds in a menu setup.
One thing that can be done in the menus is to program a button for what Sony calls “zoom assist,” which, when pressed, zooms the lens out as long as the button is pressed and then snaps back to the previous zoom distance when released. This is great for shooters trying to follow erratically moving animals or other subjects that move too quickly to stay framed at 600mm.

The image quality from the Sony-designed sensor in the RX10 III is at the top of its class, thanks to a few technological factors. The first is the “stacked” design, which allows information to move from the sensor to the processor very quickly, allowing the camera to perform corrections in-camera more quickly than possible with other sensors. The second, and more important image quality factor is that the sensor is backside illuminated, giving it good performance in low light.

While the camera is tops for the 1” sensor market, there’s still a big quality jump between a 1” sensor and an APS-C and an even bigger jump between 1” and full frame. If you’re not going to shoot at long focal lengths, you’d be better served by buying an a6300 or a7 II and the lens of your choice than the 1”-based RX10 II. That’s because while the low-light sensitivity is improved through the sensor design, the relatively low dynamic range is not.

Dynamic range is, simplistically speaking, the number of shades between white and black that a camera can reproduce. The more dynamic range, the more detail you can see in highlights and shadows. Because of physics, a larger sensor will have more dynamic range than a smaller one, all things being equal. That means that a 1” sensor has less dynamic range than a similar resolution APS-C sensor and much less than a full frame. The RX10 II (which has the same sensor as the RX10 II) has been measured as having around eight stops of dynamic range (you can see detail across eight stops of light difference, but you lose detail after that). The Sony a7R II has around fourteen stops. (Both numbers are for ISO 100 shooting.)
The independent review site DXOMark.com has slightly different numbers, with a closer level of dynamic range, though that doesn’t match my real world tests. Even assuming a 1-2 stop difference, that’s a huge amount of additional light gathering.

What this means is that the RX10 III is less able to capture detail in scenes with wide dynamic range compared to something like the a6300, 7R II or even the a7S II (which also has about fourteen stops). There is a bit of apples-to-oranges comparison here, the a7sII and the a7RII both cost more (and in the case of the a7R II a lot more) than the RX10 III but with a $1500 price tag, it’s fair to compare the image quality to other offerings.

That’s because the target market for this camera seems to be the landscape and wildlife photographer, as well as the travel photographer. Travel photographers are less stringent when it comes to dynamic range as a general rule, but landscape and wildlife photographers need all the dynamic range they can get. When you’re shooting in the slot canyons of Zion Natioanl Park, you want to be sure to capture all the details possible in the scene, after all, that’s what you’re out shooting.
That makes the Sony RX10 III an interesting camera. The Canon G3X is less than half the list price of the RX10 III, and DXOMark gave the G3X a score of 63 and the RX10 II a score of 70. Assuming that the RX10 III (which has the same sensor as the RX10 II) that’s very, very close, and arguably not worth a $700 difference in price.

So what’s that extra $700 for, as Sony clearly does market research and is price sensitive. The answer is video, video, video. Videography is so important to Sony that the launch event for the RX10 II was surrounded by global announcements about new 4K televisions and Sony’s new 4K UHD re-mastered movie service.

That brings (in a rather lengthy route) us to a conclusion that for the still photographer that does no video, the RX10 III is far too expensive (by about 50%) for the average shooter the Canon G3X would be a better bet. Shoot 4K video, though and the RX10 III suddenly becomes a super-star. Sony’s 4K video, with it’s oversampling, gives it incredible quality, well worth the price tag. The stacked sensor allows the 4K to process fast enough to shoot at pro-level resolution. Video has lower dynamic range than stills anyhow, so that’s not an issue.

In conclusion, the RX10 III is a fascinating camera, albeit one with a very specialized audience. It’s looking for the customer with a need for both stills and 4K video (or still and slow-motion video) and the money to justify the purchase of a camera that’s going to do everything well, but nothing perfectly.
At the end of the day, that’s the deal with many all-in-one compact cameras. Each carves out a part of a niche market and competes for that segment of the user base. By comparison an interchangeable lens camera system can allow the photographer to mix and match lenses and bodies to suit various conditions.

Should you buy the RX10 III? If you’re looking for a wide-zoom 4K camera with excellent image quality, yes. If you’re a stills-only shooter looking for a wide-zoom travel camera on a budget, the RX10 III is out of your league. Sony proudly talked of the image quality in the lens of the RX10 III, and the one-stop better performance at the long end. That’s great, but I’ve shot the G3X and images from it are as exceptional as those from the RX10 III, even if one stop smaller.

For $700 vs, say $1000, I’d have no hesitation to recommend the RX10 II to any landscape or travel shooter looking to lighten their camera bag. With a $700 or so difference in price, the suggestion is to evaluate how much video will be captured and purchase accordingly. If Sony had priced the RX10 III on par, or just a tad above the Canon G3X it would be an unmitigated home run.
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