The Sony RX100 III, meanwhile, will have an edge shooting in bright sunlight where LX100 users will be forced to stop down sooner. Doubly so because the RX100 III includes a built-in three-stop neutral density filter, which feature the LX100 lacks.
And the Sony also offers higher sensor resolution, which could be important if you need to make large prints or want to crop significantly. With an effective resolution of 20.2 megapixels in 3:2 aspect, the RX100 III offers about 28% higher linear resolution than does the 12.8-megapixel LX100, on paper at least. (Again, we'll need to get the Panasonic through our in-depth lab testing to confirm the real-world difference between the two cameras in this area.)
Similar optics, but perhaps a slight edge for Panasonic
Despite the difference in body and sensor size, the built-in optics of the Panasonic LX100 and Sony RX100 III are actually pretty similar, on paper at least. Both cameras' lenses carry premium branding, have around a 3x optical zoom range with similarly bright apertures across that range.
In terms of maximum aperture and zoom range, the cameras are evenly matched. Both lenses start from a 24mm-equivalent wide-angle, although at this point the LX100's f/1.7 maximum aperture is just a touch brighter than the f/1.8 of the RX100 III. At telephoto, both cameras' maximum aperture falls to a still-bright f/2.8, but the LX100's 75mm telephoto is a touch longer than the RX100 III's 70mm tele (in 35mm equivalent terms).
The LX100's claimed autofocus time is 0.14 seconds. That's similar to the 0.15 second we measured for the RX100 III, but a final verdict will have to wait till we get the LX100 into our labs. One worthwhile note is that Panasonic provides 49 AF points for the LX100, versus just 25 points in the RX100 III.
On a first look, the cameras appear quite similar in the optical department, but these figures say nothing of real-world sharpness, distortion, vignetting and aberrations. It's pretty common for cameras in this class to make radical corrections to their images to account for the compromises inherent in making such compact, bright zooms for comparatively large sensors. Watch this space for the rest of the story!
The LX100 features manual controls aplenty, while Sony caters more to beginners
While both the LX100 and RX100 III have a surprising number of external controls given their relatively trim, compact bodies, the Panasonic LX100 is the more generously-equipped of the pair when it comes to physical controls. In fact, it just feels more like a camera that was made with experienced photographers in mind, whereas the Sony RX100 III clearly caters to consumers.
Glance at the Sony and you'll see a friendly Mode dial, one of only three dial/ring-type controls on the RX100 III's body. By contrast, the Panasonic LX100 has five dials and rings, and forgoes a Mode dial altogether. Instead, you get dedicated controls for the main exposure variables -- shutter speed, aperture, and exposure compensation. A second lens ring behind that used to control aperture can be configured to control lens zoom, ISO sensitivity and manual focus, among other options.
And while the Sony has but one customizable function button -- used to call up seven different functions which you then adjust by rotating the lens ring -- the Panasonic LX100 has three configurable function buttons.
And the difference in these two cameras' nature is more than skin deep, as well. If you're a less experienced photographer, you'll appreciate the Sony RX100 III's array of 13 scene modes that help you get the results you want without the need to understand much in the way of camera setup (though you will have to divine the difference between Intelligent Auto and Intelligent Auto+ modes). The Panasonic, though, forgoes such niceties altogether: Its only concession to approachability is an Intelligent Auto mode accessed with a dedicated button on the top deck.
Panasonic stakes its claim to the performance crown
One area in which there looks likely to be a clear winner is in the performance department. While our final verdict will have to wait until we've completed our own independent testing, the Panasonic LX100 looks poised to beat Sony's well-entrenched rival in the performance department, on paper at least.
Based on manufacturer ratings, the LX100 beats the RX100 III in terms of burst performance, whether or not autofocus is enabled. (And the difference when AF is active is significant: Panasonic rates its camera for 6.5 frames per second, more than double the 2.9 fps rating provided by Sony.) And the Panasonic LX100 can edge out its rival even without autofocus, too, shooting 11 frames per second, one more than the RX100 III. If you're willing to live with the downsides of a fully-electronic shutter, the LX100's performance rockets to 40 frames per second, but resolution is slashed to just three megapixels.