It was just about a year ago that I reviewed the Sony RX10 Mark III for another publication. I was impressed then and even more impressed now. That’s because this update adds the a9 image processing to a compact body already chock full of Sony’s tech.
If you consider the camera for more than the specs and where it sits in the marketplace, it’s another marvel of miniaturization. The third update increases the zoom from 200mm to 600mm, and the fourth update makes this camera unique for all that it can do. As I observed during the launch, the RX10 Mark IV is a camera for enthusiasts and professionals who need a combination of image quality, telephoto reach and shooting speed.
Regarding speed, in just a few hours during a sunny afternoon in New York, I filled an SD card, and then some—2,305 photos, to be exact—and below I grabbed a few picks to share. Note that I shot with a pre-release camera and edited JPEGs only with minimal processing.
A joke around the dinner table, as the media and Sony staffers unwound following the launch of the RX10 Mark IV, was:
“Where’s the Willy Wonka room at the factory?”
It seems like every relentless six months or so, Sony releases a new groundbreaking mirrorless camera with “whoa” features that get the press talking, including me, and here’s why: It’s like their tech is from the future and there’s more to come.
The Sony a9 crossed the mirrorless event horizon, and I imagine there’s a product designer, designing in a category, say, like travel, who gets the keys to the Wonka room for an hour and comes out with a hot sheet of tech to deploy.

While that’s an exaggeration, and a cocktail-party joke, there’s much about the RX10 Mark IV that’s futuristic:
- Stacked CMOS Exmor RS 20-megapixel sensor—The same sensor as the RX100V with DRAM onboard so the pipeline to the SD card doesn’t slow (that’s with the fastest SD card).
- 315 Phase-detect AF points (the most accurate way to autofocus)—Phase-detect AF is much more accurate than contrast-detect and the main feature of the RX10 Mark IV.
- 24 fps with tracking AF—That’s faster than the a9, and the RX10 Mark III is 14 fps. Because the still camera frame rate is the same as 24P, you can shoot movies with 20 MP stills, like a long animated GIF.
- 249 frame limit for RAW bursts at 24 fps—So, you can also look at it as getting 10-second 8K bursts at 24P. That’s one of those “wow” moments, and while the practicality is limited, imagine a time-lapse-style scene.
- Leaf shutter—Like the other cameras in the RX series, the Mark IV has a leaf shutter, which means you can sync strobes up to 1/4000th
- A 24-600mm ƒ/2.4-4.0 lens—This is a Zeiss lens, and it’s sharp. A fixed lens means you won’t have to clean the sensor.
- Back Button AF—Previous revisions of the RX10 didn’t have back button AF; this one does.
- 5 stops of image stabilization onboard—The Optical SteadyShot is equivalent to a 4.5-step faster shutter speed.
- 120P Full HD, 24P and 30P 4K— Just add the XLRK2M for a pro-level shotgun mic, and the RX10 Mark IV can be your main shooter, again, for those interested in this unique combination of technologies.
While it seems like it’s from the future, you can get the RX10 IV next month for $1,700, and if you shoot outdoors and prefer a fixed lens, I recommend you do.
In the hand, the body feels lighter than it looks because of the room needed to house the zoom lens. It will take a few shoots to get used to the Tight/Wide zoom toggle. I turned the camera off, mistaking that button for the zoom several times. While the body is the same as the Mark III, there’s a new programmable function button on the right side of the lens. I’d use that for Eye-AF or something similar. As with all Sonys with touch-screens, I turn off the touch focus unless I’m capturing video. It seems when looking through the viewfinder my nose touches the screen and moves the focus point around.
The images that 1-inch sensor can produce is the marvel of Sony’s processing tech, and combined with the speed of the a9, you can fill an SD card, as I did, and most likely get the shot. Considering a 25x zoom, and top-speed AF, the camera follows Sony’s design intent of putting a photographer in the moment, allowing them to be creative with the tech getting out of the way.
To that point, I’m not a nature shooter, preferring the street and the bike, but I could imagine tossing the camera into my backpack, riding to a location and photographing wildlife. Before shooting with the RX10 III or IV, I hadn’t considered such a thing. I can even shoot in Seattle’s wet winter months because the body is ruggedized.
I know from reading David Schloss’ post last month that Sony’s factories are nothing like Willy Wonka, but the products they ship do seem to come from a world of pure imagination.