Upgrade Guide
Sony A7S III→Sony FX3
Is it worth upgrading? Spec analysis, key improvements, and our verdict.
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Situational
One clear hardware improvement over the A7S III. Worth it if that specific upgrade aligns with what you shoot.
What's new in the FX3
-
Generation1 year newer (2021 vs 2020)
Unchanged or similar
-
ResolutionSimilar (12MP)
Suitability by genre
| Genre | A7S III | FX3 | |
|---|---|---|---|
| Video | — | ||
| Wildlife | — | ||
| Street | -5.0 | ||
| Portrait | — | ||
| Travel | -3.0 | ||
| Vlogging & Video | — | ||
| Low Light | — | ||
| Wedding | — |
Full spec comparison
| Spec | A7S III | FX3 | |
|---|---|---|---|
| Price | £2,999 | £3,799 | |
| Released | 2020 | 2021 | ↑ |
| Sensor | 12.1MP Full-Frame BSI CMOS (12-bit, back-illuminated) | 12.1MP full-frame BSI Exmor R CMOS (same as A7S III) | |
| Resolution | 12MP | 12MP | |
| Video | 4K/120p 10-bit, 4K/60p 10-bit S-Cinetone/S-Log3, 1080p/240p | 4K/120p, 4K/60p 10-bit, 12-bit RAW output, S-Log3, S-Cinetone | |
| Autofocus | Phase-detect, 759 points, real-time Eye AF (human & animal), subject recognition | Real-time tracking with subject recognition (human, animal) | |
| Stabilisation | 5.5-stop IBIS | 5-axis IBIS — 5 stops | |
| Burst Rate | 10fps mechanical | 10fps mechanical, 10fps electronic | |
| Battery Life | ~600 shots (CIPA) / ~70min continuous 4K recording | ~640 shots (CIPA) | ↑ |
| Weight | 699g (body, battery, card) | 715g body only (with XLR handle) | ↓ |
| Weather Sealed | Yes | Yes | |
| Viewfinder | OLED EVF, 9.44M dots, 0.90× magnification — best EVF Sony has made | None — monitor/external EVF use only | |
| Screen | 3.0" vari-angle touchscreen, 1.44M dots | 3.0" touchscreen, fully articulating | |
| Mount | Sony E-mount | Sony FE mount (full-frame E-mount) | |
| Memory Cards | Dual CFexpress Type A / SD UHS-II (both slots) | Dual CFexpress Type A / SD UHS-II slots |
Compare side-by-side
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