Sony
A7S III 2020
Best for Professional video & low-light filmmaking
£3389
new today at Clifton Cameras
Decision tools · Compare
A7S III vs Sony FX5
Quick take: The Sony FX5 has the highest resolution at 17MP; the A7S III is the most affordable.
16 specs side by side·15 genres scored·UK prices from Wex Photo Video and Clifton Cameras
How to read this page. Highlighted cells win that row on the spec alone. Genre scores are the engine's base scores (enthusiast, photo and video); Camera Match re-weights them for your level and priorities. Price buttons are affiliate links; the price you pay is the same.
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Verdictwhich should you buy?
A7S III — Professional Video & Low-Light Filmmaking: If video is your primary discipline, the A7S III is the camera. 4K/120p at 10-bit in a weather-sealed body with a 9.44M dot EVF is an extraordinary package. The 12MP sensor isn't limiting for video — and it's usable at ISO 409,600 in a pinch.
Who should buy what
A7S III (2020)
is the right camera for you if…
- Filmmakers and videographers who need 4K/120p at 10-bit
- Event videographers who shoot in dark venues regularly
- Documentary filmmakers who need reliable AF and weather sealing
- Hybrid shooters where video is primary and stills are secondary
Full specificationsthe better value in each row is highlighted
| Specification | A7S IIISony · 2020 | Sony FX5Sony · 2026 |
|---|---|---|
| Price | £3,389Best | £4,699 |
| Sensor | 12.1MP Full-Frame BSI CMOS (12-bit, back-illuminated) | 16.6MP full-frame stacked Exmor RS CMOS |
| Resolution | 12.1MP | 16.6MPBest |
| Video | 4K/120p 10-bit, 4K/60p 10-bit S-Cinetone/S-Log3, 1080p/240p | 5K/60p open-gate, 4K/120p, internal RAW/X-OCN, 10-bit Log, triple base ISO |
| Autofocus | Phase-detect, 759 points, real-time Eye AF (human & animal), subject recognition | AI-powered hybrid phase-detect AF (759 points) with subject tracking |
| Stabilisation | 5.5-stop IBIS | IBIS with Dynamic Active Mode |
| Burst Rate | 10fps mechanical | 10fps |
| Battery Life | ~600 shots (CIPA) / ~70min continuous 4K recordingBest | ~105 min actual recording, ~170 min continuous (LCD) |
| Weight | 699g (with battery and card)Best | 734g (with battery and card) |
| Dimensions | 128.9 × 96.9 × 80.8mm | — |
| Weather Sealed | Yes | Yes |
| Viewfinder | OLED EVF, 9.44M dots, 0.90× magnification — best EVF Sony has made | Optional detachable EVF (DVF-EL1), OLED |
| Screen | 3.0" vari-angle touchscreen, 1.44M dots | Fully articulating touchscreen (4-axis arm) |
| Mount | Sony E-mount | Sony E-mount |
| Memory Cards | Dual CFexpress Type A / SD UHS-II (both slots) | CFexpress Type A + SDXC (dual) |
| Connectivity | USB-C (USB 3.2 Gen 2), full-size HDMI, Wi-Fi 6, Bluetooth | USB-C, full-size HDMI, Wi-Fi, Bluetooth |
Wins the row — price, resolution, burst, battery, weight and sealing are compared; text specs aren't ranked.
How they score by genreengine base scores out of 10
Genre
A7S III
Sony FX5
Portrait
7.5/10
6.9/10
Street
6.2/10
5.3/10
Travel
6.2/10
6.2/10
Wedding & Events
7.5/10
7.0/10
Vlogging & Video
6.1/10
6.1/10
Filmmaking
8.2/10
8.7/10
Documentary
7.7/10
8.3/10
Sports & Action
7.4/10
6.8/10
Landscape
5.5/10
5.1/10
Wildlife
7.5/10
6.8/10
Casual
4.9/10
5.1/10
Food
6.8/10
7.4/10
Macro
5.8/10
5.2/10
Architecture
5.5/10
6.1/10
Astrophotography
7.8/10
6.7/10
Scores come from the same engine as Camera Match: verified specifications weighted by what each genre needs, with documented adjustments. The product page and this table show the enthusiast base score. See how scores are calculated →
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