Sony’s latest A7 cameras represent the vanguard of the mirrorless camera movement because they’re the most accessible full-frame systems on the market. The A7 III and A7R III are smaller, lighter, and more durable than their DSLR counterparts, and have narrowed the gaps in image quality, performance, and lens selections.
These two new cameras are directly related to Sony’s flagship released last year: the sporty $4,500 A9. In fact, everything from EVF design, to the grip, controls, SD card slots, and software are derived in some form from their big brother, the A9.
The A9 has all of Sony’s bells and whistles, but it comes with a price tag to match. The new A7 models, however, bring many of the A9’s advancements down to more pedestrian price levels. These are certainly still professional level cameras — the A7 III runs for $1,999 without a lens, while the higher-resolution A7R III commands $3,199 — but the difference in price from the A9 leaves a lot of room for lenses or other necessary equipment.
It’s easy to determine if the A9 is right for you: if you don’t shoot high-speed sporting events, it’s probably too much camera. But Sony’s made it a bit tougher to distinguish between the newest A7 models, so I’ve put them head-to-head for this comparison.
The new A7 models are the third generation of Sony’s professional mirrorless line, so their main features are well known at this point. But just to recap: these are professional-level cameras with full-frame image sensors that are significantly smaller and lighter than comparably equipped DSLRs from Canon or Nikon.
Despite a nearly $1,200 price difference, the A7R and the A7 III are more related than one might assume.
Starting with sensors, they both use a backside illuminated (BSI) structure, a novel arrangement allowing the sensor to perform better in low light. Sony was the first to put this tech in a mirrorless camera with the original A7R. However, BSI structure sensors aren’t a Sony exclusive — they’ve been found in the iPhone 4S, Nikon’s D850 pro camera, and even the HTC Evo 4G smartphone.
The A7R III uses a 42.4-megapixel sensor while the A7 III tops out at 24.2 megapixels. Thanks to the BSI tech, both full-frame sensors are able to capture more light than conventional sensors. Compared to a conventional sensor and previous generation Sony Alpha, the BSI chips process data faster and produce images with less noise.
In terms of light sensitivity, there are some differences: the A7 III has a native range of ISO 100-51,200, with extended levels low as 50 and as high as 204,800. Meanwhile, the A7R III goes up to 32,000 (native) and 102,400 (extended), making the A7 the better low-light performer on paper (spoiler: it is in practice, too).
Both cameras have the same dimensions (though the A7 is 7 grams lighter), shoot video at 4K up to 30fps or 1080p at 24 / 30 / 100 / 120fps, use the same battery, have dust / moisture resistance thanks to a magnesium alloy frame, and are equipped with dual UHS SD card slots. They also both use the X AVC S codec for video, with creative styles (vivid, natural, mono, etc.) to drastically change the color profile of your photos.
Some other commonalities between the two cameras, include the Wi-Fi / NFC / Bluetooth radios, USB-C port and tethering, 1 / 8000s max. shutter speed (1 / 250s flash sync), max 10fps with AF / AE tracking (8fps with live view / blackouts), 14-bit RAW (compressed or uncompressed), and finally, the exact same button layout with the exception of a shooting mode lock button on the A7R (a useful feature seen on the A9).
Ports-wise, both cameras share mic input, headphone output, USB 2.0, USB Type C, and Micro HDMI Type D. Still, the A7R III edges it out with an extra port for flash synchronization.
Of course, let’s not forget batteries. Both cameras use Sony’s new NP-FZ100 battery. It’s a big improvement over the last battery model used in the Alpha range, which was criticized for being small and inefficient. In real-world usage, I get around 600 shots before depleting the A7R. The A7 III fairs better, at over 700 photos before needing a charge.
That’s enough to make it through a day of casual shooting or at least one studio shoot on a full charge, probably with either camera. But if you’re using these for event photography, you’ll definitely want a spare battery or two charged up and ready to go.
Both cameras have 3-inch touchscreens — the A7 III’s at 921,600 dot resolution while the A7R has a better 1,440,000 dot version — but that feature is only useful for tapping the screen to focus. Nothing else. Unfortunately, Sony disabled them or mostly everything else they’d be useful for, like navigating the 36 pages of settings (please Sony, redesign the interface). My advice is to get familiar with creating custom settings to avoid the byzantine menu system.
Let’s talk about the A7R first. This is the best camera Sony has ever produced when it comes to dynamic range (15 stops) and resolution (42.4MP). In short, it can take some incredibly crisp and vibrant photos in a wide range of lighting situations.
It can even retain the dynamic range while in burst mode! It’s awesome and incredibly useful in scenes where you don’t have time to fiddle around with settings, but also want different versions of the same photo. Also, you can turn it off completely, or have it run automatically so you don’t have to worry about how to set it up.
Despite having fewer total AF points than the A7 III and the A9 (399 compared to 693 points) that cover 68 percent of the sensor area, both cameras have the same number of contrast detection points (425), so that’s okay. The majority of AF points are centered in the frame, allowing the joystick to become the perfect precision tool for picking your foci. In practice, the A7R III system still yields fast and accurate AF like the A7 III’s, just not with as many points.
To make 42MP stills and 4K video actually useful, the picture needs to be sharp. The A7R has Sony’s famous five-axis stabilization system, which when used with optically stabilized lenses, employs three axes on the sensor and the two inside the lens. The A7R’s official specification for this is 5.5EV, but this isn’t much better than the A7 III’s 5EV rating.
However, the A7R struggles below one-fourth second shutter speeds, producing washed-out images and with slower autofocus. The A9 and A7 III both performed better in these scenarios. Another area where high resolution held the A7R back was with image buffering, obviously. With large 42-megapixel files to write at 10fps, you can only save 76 frames in JPG or 76 in compressed RAW format. The A7 III clicks away at 10fps, too, but it can shoot 177 JPGs or 89 RAW images before its buffer fills up and shooting screeches to a halt.
In addition, the A7R III has another gimmick, a feature called PSMS (Pixel Shift Multi Shooting). Basically, it takes four images in a row by moving the sensor a pixel between each shot. The four images are then composited into one frame, with supposedly better detail and color accuracy, without hampering the 42MP resolution. It’s different than other pixel shifting techniques, such as Hasselblad’s, which aim to increase the resolution output.
Here’s the catch: it won’t work hand-held, won’t work on a moving object, and finally, can’t even be stitched together on the camera; instead you need Sony’s free Imaging Edge software for Mac or PC. It works, but the results aren’t mind-blowingly different from a regular old photo shot on the A7R.
Of course, a photographer purchasing a $3,000+ camera isn’t going to solely rely on the rear screen for taking photos in live view mode. What you’d need is a great EVF (electronic viewfinder) that’s only comfortable and pleasing, but useful as a information tool, with accurate framing and high resolution. The A7R wipes the floor with the A7 III in this category.
On paper, it would appear as if the A7R trounces the A7 III. But this is the real world, where the sum of parts matter. To recap, the A7 III can shoot and save more images at a time than the A7R. It performs better in low light, has better battery life, and thus is the more practical “prosumer” camera.
Moreover, it takes up less hard drive space during post-production. The A7 III is just an easier camera to live with than the A7R, especially when it comes to filling up SD cards — 479 extra fine JPGs and RAWs total 14.7GB with the A7R. However, keep in mind none of that makes the A7R the worse camera, just different.
Both cameras feature 15 stops of dynamic range and the results are incredible. In layman’s terms, that’s 15 different brightness compositions of a photo, which even works in burst mode. Basically, it’s difficult to get a bad photo with the A7 III, even in its manual modes.
One thing I’ve found with shooting subjects and portraits with the A7 III is that it’s “just right” — the A7R’s megapixel count is sometimes too high and too detailed for certain scenes, such as close-ups.
But, here’s my main gripe with the A7 III: it doesn’t inherit the electronic viewfinder from the A7R or the A9. Instead, it uses an older OLED panel (same as the A7 II) with a slower 60fps refresh rate. The magnification is the same as the A7R (0.78x) due to similar optical design, but the 2,359,296 dot screen is far lower-resolution than the R’s viewfinder, which clocks in at an insane 3,686,400 dots. The differences in quality were even more obvious when I shot in low light or up-close.
Obviously, cost restraints are a factor but part of me also feels that if Sony included the new EVF in the A7, there’d be fewer reasons to consider the A7R III — and obviously you don’t alienate your own mid-range mirrorless camera. Otherwise, the A7 III has it all and is suitable for most users.
On both cameras, I tested the Sony FE 24-105mm, the 85mm prime, and the FE 28-70mm f/3.5-5.6 stabilized kit lens. Of the three, the kit lens was my least favorite and the 85mm prime lens a strong second, the 105mm lens being my favorite. Unsurprisingly, they offer better clarity and focus than the kit lens, which is to be expected from Sony’s premium (and premium-priced) G Master lenses.
The A7R had more drastic differences in terms of clarity over distance and zooming in on close subjects (those extra pixels really highlight details). The A7 III fairs just as well with the different lenses, but the smallest of details aren’t as apparent. Still due to similar BSI sensors and color profiles, composition and focus are very much alike. Comparing shots side by side, the A7R has the edge in pixel density, but that’s about it — the results don’t make a scene “more beautiful,” simply due to the megapixel count.
Take a look for yourself at the below example shots. If the galleries weren’t labeled, would you be able to tell them apart?
For video, both cameras shoot 1080p up to 120fps and 4K at either 24 or 30fps. These aren’t camcorders, but the 24fps option on the Sony Alphas is some of the best you can get in a mirrorless camera right now. 4K is also impressive since both Alphas are technically compressing footage slightly higher than 4K at 35mm, into a standard 4K shot.
Sony also adds support for gamma curves, allowing you to correct for different lighting situations while filming and ultimately, a different style for every curve. Videographers will appreciate this feature more than anyone else.
The A7 III is the more complete mirrorless camera package, with the latest Sony AF system in tow. The A7R is better suited for highly detailed work, can take more pixel-rich photos, and can better assist you due to the better EVF and resolution.
If you’re a landscape, fine art, or still life photographer or you’re in the realm where pixel quality and image resolution is a major key, the A7R is the more appropriate camera. Things like 4K recording and the Pixel Shift feature would just be welcomed additions to your tripod-assisted, landscape shooting.
However, if this is your first mirrorless, or you need to upgrade from prior Alpha cameras, buy the A7 III. Especially if you shoot a bit of everything and everywhere (sports, subjects, landscapes, urban). The larger image buffer gives you more flexibility in the moment, with as many AF points as the sports-oriented A9. It’s also slightly lighter and of course $1,200 less expensive.
Ultimately, you can have fantastic all-around performance with the A7 III or megapixel overkill with the A7R III. Both are great cameras, but one is far more suitable for the niche of professionals who specialize in detail-oriented photography, while the other is going to be on many new photographer’s wishlists.