Don’t be fooled by the release dates – the Sony a7R IIIA and the Sony a7 III are two cameras from the same generation, just targeted at different users. The Sony a7R IIIA is a high-resolution (42 megapixel) machine for landscape photography, while the a7 III is a very similar camera but with 24 megapixels instead.
Technically, the a7R IIIA is more than three years newer, but that’s misleading. Below the surface, it’s an extremely minor minor refresh of the Sony a7R III (which actually came out a few months before the a7 III)! Sony basically just added a higher-resolution rear LCD screen and tacked an “A” onto the end of the model name. Nevertheless, the a7R III is officially discontinued, so that’s why I’m comparing the Sony a7R IIIA against the Sony a7 III today.
Sony a7R IIIA vs Sony a7 III Specifications Comparison
|Camera Feature||Sony a7R IIIA||Sony a7 III|
|Announced||April 2021||February 2018|
|Sensor Type||BSI CMOS||BSI CMOS|
|Image Processor||BIONZ X||BIONZ X|
|Resolution||42.4 MP||24.2 MP|
|Sensor Dimensions||35.9 x 24.0 mm (Full Frame)||35.6 x 23.8 mm (Full Frame)|
|Sensor Pixel Size||4.51µ||5.93µ|
|Low Pass Filter||No||No1|
|IBIS (In-Body Image Stabilization)||Yes||Yes|
|Base ISO||ISO 100||ISO 100|
|Max Native ISO||ISO 32,000||ISO 51,200|
|Extended ISOs||ISO 50-102,400||ISO 50-204,800|
|High-Resolution Sensor Shift||Yes||No|
|Focus Stack Bracketing||No||No|
|Pre-Shoot Burst Mode||No||No|
|Fastest Shutter Speed||1/8000||1/8000|
|Longest Shutter Speed||30 seconds||30 seconds|
|Continuous Shooting (Mechanical Shutter)||10 FPS||10 FPS|
|Continuous Shooting (Electronic Shutter)||10 FPS||10 FPS|
|Notes for High FPS Shooting||Compressed 12-bit raw at 10 FPS (uncompressed 14-bit raw is available at 6 FPS)||None|
|Buffer Size (Raw)||76 frames (10 FPS)||89 frames (10 FPS)|
|Autofocus System||Hybrid PDAF||Hybrid PDAF|
|Low-Light AF Sensitivity (f/2 Lens, ISO 100)||-3 EV||-3 EV|
|Standard Flash Sync Speed||1/250||1/250|
|Curtain to Protect Sensor at Shutdown||No||No|
|Maximum Video Bit Depth (Internal)||8 bits||8 bits|
|Maximum Video Bit Depth (External)||8 bits||8 bits|
|4K Maximum Framerate||30 FPS||30 FPS|
|1080P Maximum Framerate||120 FPS||120 FPS|
|Additional Video Crop Factor||No||No|
|Chroma Subsampling||4:2:0, 4:2:2 (External)||4:2:0, 4:2:2 (External)|
|Video Recording Limit||30 min||30 min|
Physical and Other Features
|Slot 1 Type||SD (UHS-II)||SD (UHS-II)|
|Slot 2 Type||SD (UHS-I)||SD (UHS-I)|
|Rear LCD Size (Diagonal)||3.0 in||3.0 in|
|Rear LCD Resolution||2.36 million dots||0.92 million dots|
|Articulating LCD||Single Axis||Single Axis|
|Viewfinder Resolution||3.69 million dots||2.36 million dots|
|USB Type||Type C 3.2 Gen 1||Type C 3.1|
|Battery Life (Viewfinder)||530 frames||610 frames|
|Battery Life (Rear LCD)||640 frames||710 frames|
|Weight (Body Only w/ Battery + Card)||657 g (1.45 lbs.)||650 g (1.43 lbs.)|
|Dimensions (LxHxD)||127 x 96 x 74 mm (5.0 x 3.8 x 2.9″)||127 x 96 x 74 mm (5.0 x 3.8 x 2.9″)|
|MSRP, Body Only||$2200 (Check Current Price)||$2000 (Check Current Price)|
|Used Prices||Sony a7R IIIA Used Prices||Sony a7 III Used Prices|
|1It is unconfirmed whether the Sony a7 III has a low-pass filter. The general (and perhaps surprisng) consensus is that it does not, or if it does, it is a weak horizontal-only AA filter.|
Clearly, these two cameras share the vast majority of their specifications! Even in areas where one camera is ahead, it’s usually not by much (like in buffer capacity, where the a7R IIIA manages 76 frames compared to 89 frames for the a7 III). The Sony a7 III arguably has the better autofocus system with more points spread across the frame. Otherwise, the biggest difference worth noting is what I mentioned in the intro: The a7R IIIA has a 42 megapixel sensor, while the a7 III has 24 megapixels.
The Sony a7R IIIA also has a sensor-shift mode that allows you to record full color data at each pixel. The final megapixel count of your photos remains 42 MP, but the level of detail is increased substantially. However, it only works when shooting from a tripod, and you need to use Sony’s Imaging Edge software to combine the images yourself. Landscape and architectural photographers will still appreciate this feature, but keep those caveats in mind.
Summary and Recommendations
Seeing as though these are pretty similar cameras, with the main difference being in resolution, the obvious question is how much you’re willing to pay for some extra megapixels. Bought new, there’s only a $200 difference between them (sometimes a bit greater if sales are going on) so I would just recommend the a7R IIIA at that point. It’s a low cost for a nice bump in resolution.
Then again, on the used market, pricing differences are more significant. You can easily find the a7 III for under $1000 used, while the a7R IIIA (or the a7R III) will be at least a few hundred dollars more expensive.
Megapixels are overrated, but they’re not irrelevant. I personally think that the price differences are small enough that you should just go with the a7R IIIA and don’t look back. But if you find a good deal on the a7 III, go for it – it’s an excellent camera, too.
Finally, keep in mind that both of these cameras are older models in their lineups. You could pick up a newer Sony a7R IV, a7R V, a7 IV, etc., if your budget is higher.
What does the Sony a7R IIIA offer over the Sony a7 III?
- 1.75 times more megapixels (42.4MP vs 24.2MP)
- Higher resolution rear display and electronic viewfinder, making photography more enjoyable
What does the Sony a7 III offer over the Sony a7R IIIA?
- Slightly better battery life overall, both in the viewfinder and with the rear LCD
- Lower price, costing $200 less new – and the difference is greater on the used market
- More autofocus points and arguably a slightly better autofocus system as a whole
Questions? Go to our forum, where you can start a conversation and talk to photographers about these two cameras!