Sony RX100 III Technical Info

by Mike Tomkins

The Sony RX100 III takes the design of the incredibly popular Cyber-shot RX100 and RX100 II, and overhauls them to produce -- you guessed it -- the 20-megapixel Sony RX100 III. And boy, is this ever one cool camera, with major updates throughout.

A brighter, shorter lens

For our money, the new Zeiss Vario-Sonnar T*-branded lens is the big story. Although the lens shared by the original RX100 and RX100 II had a bright f/1.8 maximum aperture at its 28mm-equivalent wide angle, by the time you zoomed all the way to the 100mm-equivalent telephoto position, the aperture closed down to a rather dim f/4.9. There's no such worry for the RX100 III, as its lens is bright across the zoom range, starting from f/1.8 at wide angle, and remaining at f/2.8 by the telephoto position. It's also a little wider, as well, with a 35mm-equivalent range of 24-70mm. The overall zoom range is curtailed a little though, down from 3.6x in the earlier cameras to 2.9x in the new one.

Still, the generous wide angle is arguably more useful for a pocket camera that's likely to be used up close in social environments than would be a stronger telephoto.

Same sensor as the RX100 II

That's especially true when you bear in mind that with a high sensor resolution of 20.2 megapixels (from the exact same backside-illuminated chip used in the RX100 II), the new model offers plenty of room to crop your images while still retaining generous print sizes.

A record-making optic

Designing the new 10-element, nine-group optic that sits before the sensor was clearly a big task, and Sony says that it's the world's first to include two advanced aspherical elements cemented together. It also has a 7-bladed circular aperture and Zeiss T* coating.

Built-in ND filter

And the RX100 II also adds a built-in, 3EV neutral density filter, making it more likely you'll be able to take advantage of the wide aperture to blur backgrounds or avoid diffraction, even in bright light.

Closer focusing

The new lens will also focus much closer at telephoto -- around 30cm, instead of the 55cm distance of earlier models -- although you'll still get the greatest magnification by moving the camera closer, and shooting towards the wide angle position.

Built-in, popup electronic viewfinder

Importantly, Sony hasn't had to make much of an increase in body size or weight to fit in the new lens, nor to make room for the new electronic viewfinder. And that addition, too, is going to cause some excitement. Its inclusion makes the Sony RX100 III seem altogether more grown-up. Sure, you can still frame at arm's length if you want, just like the younger generation has been brought up doing. But if you want to feel closer to your subject, and to use a steadier, tripod-like stance with the camera to your eye, now you can do that too. And when you're not using the finder, it disappears into the camera body, like it was never even there.

It's a pretty nice viewfinder, as well. It derives a high resolution of 1,440,000 dots (or 800 x 600 pixels, with each pixel comprised of separate red, green and blue dots) from an Organic LED panel. The OLED sits behind an eyepiece lens with a Zeiss T* coating, just like that of the objective lens, which helps to control reflections and provide a clear view from corner to corner. And although size was at a premium, Sony has thoughtfully included a proximity sensor that allows the camera to switch between monitor and viewfinder display automatically when you bring the camera to your eye.

No external flash

To make room for the viewfinder, Sony has had to move the flash directly above the lens, and that means that -- unlike the RX100 II -- this model forgoes a flash hot shoe, as did the original RX100. But for a pocket camera like this, we think that's a fair tradeoff. Realistically, if you've got room to carry an external strobe with you wherever you go, you could probably have brought a mirrorless camera setup as well. The RX100-series cameras are for traveling light and shooting on the fly, and that's not really a style that lends itself to external flash.

Next-gen processor

Inside, the next-generation Sony BIONZ X image processor replaces the earlier BIONZ chips used by the RX100 and RX100 II. That helps reduce the impact one of relatively few criticisms we had with the Sony RX100 II: a significant reduction in Speed Priority burst rate when shooting raw images. (The RX100 III still slows, but not by so much as its predecessor.)

With the extra horsepower of BIONZ X -- it's said to have around three times the performance of the previous-generation chip -- the RX100 III gives noticeably better performance than did the RX100 II. It still shoots at 10 frames per second with focus and exposure locked, but now allows a somewhat swifter 2.9 fps with focus and metering adjustment between frames, according to Sony. By contrast, the RX100 and RX100 II shot at 2.5 fps with AF/AE adjustment, to manufacturer specifications.

Our in-house testing found that number actually slightly on the conservative side, and it also turned up performance improvements in most other areas, including startup, mode switching, autofocus, and flash recycling. More often than not, the improvements were quite noticeable, as well.

Image quality

Sony suggests that BIONZ X also allows an improvement in image quality and noise reduction, although we personally preferred the RX100 II at higher sensitivities -- and it's worth noting that Sony hasn't extended the upper sensitivity limit from that of the RX100 II. Still, that camera had an already-generous (for a compact camera) sensitivity range of ISO 160 to 12,800 equivalents, expandable to ISO 100 at the lower end.

The RX100 III can reach a little lower at the bottom end of the range, though, to match the original RX100, while retaining the upper limit of the RX100 II, for a range of ISO 125 to 12,800 with an expansion to ISO 80 available. And there's still a Multi-Frame NR function which will allow an equivalent ISO 25,600 by averaging noise out across multiple exposures for static scenes.

Sony claims that the extra power of BIONZ X shows itself in both finer detail reproduction from the 20.2-megapixel CMOS image sensor, and improved area-specific noise reduction algorithms. We agreed at base ISO, noting a slight improvement in detail, but at higher sensitivities found the new noise reduction algorithms obscured detail more than the earlier camera. It's worth noting, though, that nothing else with a similar body size and lens comes close, except the RX100 III's own siblings.


The company has also made some improvements in the autofocus department for the RX100 III, with a lock-on AF function that changes point size automatically to better track moving subjects, and a Flexible Spot AF Area setting that allows a choice of three different manually-selected AF frame sizes.

Selfie-friendly LCD monitor

Another nice touch in a camera that, as we've said, is likely to be used frequently in social situations is the RX100 III's updated LCD articulation mechanism. The original RX100 had a fixed LCD, and the RX100 II updated this with a monitor that could tilt upwards by 90 degrees, or downwards 45 degrees. The RX100 III, though, has an altogether more useful mechanism that will tilt upwards 180 degrees, or downwards by 45 degrees.

That means it's still great for shooting high above your head or low to the ground, but it also makes the camera well-suited to shooting self-portraits at arm's length. If you need to shed some light on yourself, the popup flash will unfortunately block part of the screen when flipped up, but direct flash doesn't lend itself to flattering portraits anyway, and the generous sensitivity range of the RX100 III should mean it's unnecessary most of the time.

Same (great) display

The display itself is unchanged from those of the earlier cameras. It's still a 3.0-inch, Sony WhiteMagic Xtra Fine LCD with 1,228,800 dot resolution. If you're not familiar with Sony's WhiteMagic technology, the nutshell view is that it allows either a brighter display for better visibility outdoors, or a lower backlight level for power saving the rest of the time. It works by adding a white dot alongside the standard red, green, and blue dots found at each pixel location in most LCD displays. The pixel resolution is thus VGA (640 x 480 pixels), with four dots per pixel.

Uprated movie capture

As we mentioned, Sony has also upgraded the RX100 III's movie capture capabilities in quite a few areas. Most notably, thanks to the new BIONZ X image processor, the new camera now records video by offloading the entire image sensor contents for every frame, and then downsampling to the output resolution, rather than simply line-skipping as most cameras would. That's a change we've seen in other BIONZ X-based cameras, and it's one that makes for quite an improvement in video quality, and especially makes a big difference in the prevalence of aliasing and false color.

The change to full-sensor readout is accompanied by a new XAVC S compression option, with a resolution of 1,920 x 1,080 pixels (Full HD) or below, and a bit rate of 50Mbps. It should yield noticeably higher quality than the AVCHD more typically used. Of course, if you prefer you can instead opt for AVCHD (which peaks at 28Mbps), or MP4 (which is available only at 1,440 x 1,080 pixels or below). XAVC S movies include stereo LPCM audio, while AVCHD movies use Dolby Digital AC-3 audio, and MP4 movies have AAC-LC audio.

As well as the new compression options with either 60/50p or 60/50i frame rates, the Sony RX100 III also now offers the added 24/25p frame rates of the RX100 II, and adds a 30p option, as well as a new 120p frame rate for HD (720p; 1,280 x 720 pixel) video. This last will allow a 4x slow motion effect when reduced to 30p playback.

The RX100 III also betters its predecessors in the video stabilization department, thanks to new SteadyShot Intelligent Active Mode technology. The updated stabilization algorithms now allow five-axis digital correction, with a stronger focal length crop than is applied for the earlier SteadyShot Active. (Which is still available as an option, as well.)

To help keep exposures accurate, there's now a zebra-striping function, something that's more common in the camcorder world. Sony has added the ability to output a clean feed via HDMI, and the camera's HDMI port also now supports Triluminos displays (as did the RX100 II) and 4K still image output.

Wireless communications

And like its direct predecessor, the Sony RX100 III also sports built-in Wi-Fi wireless networking connectivity, as well as Near Field Communications tech for fast pairing with Android cameras. (Sadly, Apple still resists adopting the standard in its own products.) The location of the NFC antenna has been moved to the left side of the camera, rather than the bottom, though, a location that Sony feels is more sensible.

In-camera apps

The RX100 III also adds support for Sony's PlayMemories Camera Apps, which add functionality to the camera -- sometimes for free, sometimes as a paid extra. Available apps include such things as time-lapse and star trail, and they're installed via Wi-Fi.

Wired connections

As well as its wireless connectivity, the Sony RX100 III also sports both the aforementioned Micro HDMI port for high-def video output, and a USB 2.0 High Speed data port for connection to your computer. Images and movies are stored on a single slot compatible with either Secure Digital or Memory Stick Duo cards, and this is also compatible with SDHC, SDXC and UHS-I SD cards, not to mention PRO Duo, Pro Duo High Speed or PRO HG MS Duo cards.

Good battery life

Power comes courtesy of a rechargeable NP-BX1 lithium-ion battery pack, the same type used by both earlier RX100 cameras, and the battery is charged in-camera via the Multi Terminal Micro USBĀ port. Sony rates battery life as 320 shots using the LCD monitor, or 230 shots with the electronic viewfinder, to CIPA standards. That's a little less than either the RX100 (330 shots) or RX100 II (350 shots), but still pretty good for the class.

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