The Canon EOS R5 and the Sony a7S III are both full-frame mirrorless cameras, and they even sell for around the same price, but that’s where the similarities stop. While the Canon EOS R5 is a high-speed, high-resolution beast, the Sony a7S III is a low-light and video-oriented machine. Which one is right for you? Here’s what you need to know.
Canon EOS R5 vs Sony a7S III Specifications Comparison
| Camera Feature | Canon EOS R5 | Sony a7S III |
|---|---|---|
| Announced | July 2020 | July 2020 |
| Camera Type | Mirrorless | Mirrorless |
| Sensor Type | CMOS | BSI CMOS |
| Image Processor | DIGIC X | BIONZ XR |
| Resolution | 45.0 MP | 12.1 MP |
| Pixel Dimensions | 8192×5464 | 4240×2832 |
| Sensor Dimensions | 36.0 x 24.0 mm (Full Frame) | 35.6 x 23.8 mm (Full Frame) |
| Sensor Pixel Size | 4.39µ | 8.4µ |
| Low Pass Filter | Yes | No |
| IBIS (In-Body Image Stabilization) | Yes | Yes |
| Base ISO | ISO 100 | ISO 80 |
| Max Native ISO | ISO 51,200 | ISO 102,400 |
| Extended ISOs | ISO 50-102,400 | ISO 40-409,600 |
| High-Resolution Sensor Shift | Yes (JPEG only) | No |
| Focus Stack Bracketing | Yes | No |
| Fastest Shutter Speed | 1/8000 | 1/8000 |
| Longest Shutter Speed | 30 seconds | 30 seconds |
| Continuous Shooting (Mechanical Shutter) | 12 FPS | 10 FPS |
| Continuous Shooting (Electronic Shutter) | 20 FPS | 10 FPS |
| Notes for High FPS Shooting | None | None |
| Buffer Size (Raw) | 83 frames (20 FPS), 180 frames (12 FPS) | Over 1000 frames (10 FPS) |
| Autofocus System | Hybrid PDAF | Hybrid PDAF |
| Autofocus Points | 1053 | 759 |
| Low-Light AF Sensitivity (f/2 Lens, ISO 100) | -4.5 EV | -6 EV |
| Standard Flash Sync Speed | 1/250 | 1/250 |
Video Features | ||
| Maximum Video Bit Depth (Internal) | 12 bits | 10 bits |
| Maximum Video Bit Depth (External) | 12 bits | 16 bits |
| Raw Video | Yes | Yes, externally |
| 8K Maximum Framerate | 30 FPS | N/A |
| 4K Maximum Framerate | 120 FPS | 120 FPS |
| 1080P Maximum Framerate | 120 FPS | 240 FPS |
| Additional Video Crop Factor | No | 1.1x crop at 4K 120p (otherwise no additional crop) |
| Chroma Subsampling | 4:2:2 | 4:2:2 |
| Video Recording Limit | 30 min | 780 min |
Physical and Other Features | ||
| Card Slots | 2 | 2 |
| Slot 1 Type | CFExpress Type B | CFExpress Type A, or SD (UHS-II) |
| Slot 2 Type | SD (UHS-II) | CFExpress Type A, or SD (UHS-II) |
| Rear LCD Size (Diagonal) | 3.2 in | 3.0 in |
| Rear LCD Resolution | 2.1 million dots | 1.44 million dots |
| Articulating LCD | Fully Articulating | Fully Articulating |
| Touchscreen | Yes | Yes |
| Viewfinder | EVF | EVF |
| Viewfinder Magnification | 0.76x | 0.90x |
| Viewfinder Resolution | 5.76 million dots | 9.44 million dots |
| Viewfinder Coverage | 100% | 100% |
| Voice Memo | Yes | No |
| Built-in Flash | No | No |
| GPS | No | No |
| Bluetooth | Yes | Yes |
| WiFi | Yes | Yes |
| USB Type | Type C 3.1 | Type C 3.2 Gen 1 |
| Battery Type | LP-E6NH | NP-FZ100 |
| Battery Life (Viewfinder) | 220 frames | 510 frames |
| Battery Life (Rear LCD) | 320 frames | 600 frames |
| Battery Life (Eco Mode) | 490 frames | N/A |
| Weather Sealed | Yes | Yes |
| Weight (Body Only w/ Battery + Card) | 738 g (1.63 lbs.) | 699 g (1.54 lbs.) |
| Dimensions (LxHxD) | 138 x 98 x 88 mm (5.4 x 3.8 x 3.5″) | 129 x 97 x 81 mm (5.1 x 3.9 x 3.3″) |
Price Comparison | ||
| MSRP, Body Only | $3900 (Check Current Price) | $3500 (Check Current Price) |
| Used Prices | Canon EOS R5 Used Prices | Sony a7S III Used Prices |
The differences start with the image sensor and flow from there. The Canon EOS R5 has a high-resolution 45 megapixel sensor, while the Sony a7S III has one of the lowest-resolution sensors you’ll find on any full-frame camera, ever. That certainly makes the EOS R5 a better choice if you need to print large or do extensive cropping.
Yet even though low resolution is usually considered a downside, 12 megapixels is still enough for typical prints, and especially magazine-sized or web-sized display. 12 megapixels also allows the a7S III to have a truly massive image buffer (over 1000 frames) without any compromises at 10 FPS shooting. The large pixels of the Sony a7S III also perform exceptionally well in low light – some of the best low-light performance we’ve ever seen in a full-frame camera.
Then there’s the question of video. The Canon EOS R5 is no slouch in this department, capable of internal 8K raw video for quality that beats almost anything else on the market. However, the EOS R5 has some overheating problems when filming at such high quality, while the Sony a7S III does not. Even though the a7S III maxes out at 4K recording, it has better slow-motion video features and a much longer recording limit of 780 minutes (13 hours) compared to just 30 minutes.
Summary and Recommendations
Which camera is the right choice for you? Hopefully the question is easy to answer now, considering how different these two mirrorless machines really are. The EOS R5 is a better choice for most landscape photography (with the possible exception of Milky Way photography) due to the high-resolution sensor. It’s also my pick for sports and wildlife photographers thanks to the high 20 FPS frame rate and greater ability to crop.
Meanwhile, the Sony a7S III would be my top choice for low-light event photography like concerts, weddings, and so on. Videographers would be happy with either camera, but unless you need 8K, the a7S III gets my pick here because of better thermal control and slow-motion options. Still, you can’t go wrong either way – both of these are excellent cameras for video, even though their strengths and weaknesses are totally different for stills photography.
What does the Canon EOS R5 offer over the Sony a7S III?
- 3.72 times more megapixels (45.0MP vs 12.1MP)
- Higher resolution rear display, with about 1.5x more dots, making image review in the field easier
- Faster 20 FPS frame rate for sports photography
- Internal 8K raw video recording option
What does the Sony a7S III offer over the Canon EOS R5?
- Better heat sink capabilities for recording long videos without overheating
- Longer battery life when using the viewfinder, with approximately 290 more shots according to CIPA measurements
- Better high ISO performance
- Lower price, costing $400 less
Questions? Go to our forum, where you can start a conversation and talk to photographers about these two cameras!
Photography Life is part of the KEH and B&H affiliate programs. When you make a purchase through the affiliate links in this article, we can be compensated with a percentage of each sale. If you found this comparison useful, buying anything through these links allows you to support Photography Life at no extra cost to you. Thank you for supporting our efforts!
