Canon RF 50mm f/1.8 STMvs A7S III
Canon
Canon RF 50mm f/1.8 STM (2020)
From £219
Best for Portraits, street & everyday
View Canon RF 50mm f/1.8 STM
Which should you buy?
Portraits, Street & Everyday — Canon RF 50mm f/1.8 STM (2020): The essential first prime for Canon RF shooters — f/1.8 background separation at an accessible price with near-silent STM autofocus.
Professional Video & Low-Light Filmmaking — A7S III (2020): 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)
- 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
Quick take: The canon rf 50mm f/1.8 stm is the most affordable; only the a7s iii is weather sealed. Scroll down for the full spec breakdown.
Full specifications
| Specification | Canon RF 50mm f/1.8 STM (2020) | A7S III (2020) |
|---|---|---|
| Price | £219 | £2,999 |
| Sensor | f/1.8 (max aperture) | 12.1MP Full-Frame BSI CMOS (12-bit, back-illuminated) |
| Resolution | — | 12.1MP |
| Video | 30cm minimum focus distance | 4K/120p 10-bit, 4K/60p 10-bit S-Cinetone/S-Log3, 1080p/240p |
| Autofocus | STM (Stepping Motor) — near-silent, smooth for video | Phase-detect, 759 points, real-time Eye AF (human & animal), subject recognition |
| Stabilisation | None (relies on in-body IBIS) | 5.5-stop IBIS |
| Burst Rate | — | 10fps mechanical |
| Battery Life | — | ~600 shots (CIPA) / ~70min continuous 4K recording |
| Weight | 160g | 699g (body, battery, card) |
| Dimensions | 69.2 × 40.5mm | 128.9 × 96.9 × 80.8mm |
| Weather Sealed | No | Yes |
| Viewfinder | — | OLED EVF, 9.44M dots, 0.90× magnification — best EVF Sony has made |
| Screen | — | 3.0" vari-angle touchscreen, 1.44M dots |
| Mount | Canon RF | Sony E-mount |
| Memory Cards | — | Dual CFexpress Type A / SD UHS-II (both slots) |
| Connectivity | — | USB-C (USB 3.2 Gen 2), full-size HDMI, Wi-Fi 6, Bluetooth |
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