Upgrade Guide
Sony A7R 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 A7R III. Worth it if that specific upgrade aligns with what you shoot.
What's new in the FX3
-
Generation4 years newer (2021 vs 2017)
Unchanged or similar
-
Resolution12MP (down from 42MP — optimised for low light)
Suitability by genre
| Genre | A7R III | FX3 | |
|---|---|---|---|
| Landscape | — | ||
| Portrait | -2.0 | ||
| Vlogging & Video | +2.0 | ||
| Wedding | — | ||
| Street | -3.0 | ||
| Sports | — | ||
| Low Light | — | ||
| Travel | — |
Full spec comparison
| Spec | A7R III | FX3 | |
|---|---|---|---|
| Price | £1,799 | £3,799 | |
| Released | 2017 | 2021 | ↑ |
| Sensor | 42.4MP full-frame BSI Exmor R CMOS | 12.1MP full-frame BSI Exmor R CMOS (same as A7S III) | |
| Resolution | 42MP | 12MP | ↓ |
| Video | 4K/30p (full-frame readout), 1080p/120p | 4K/120p, 4K/60p 10-bit, 12-bit RAW output, S-Log3, S-Cinetone | |
| Autofocus | 399 phase-detect + 425 contrast AF points — real-time Eye AF | Real-time tracking with subject recognition (human, animal) | |
| Stabilisation | 5-axis IBIS — 5.5 stops | 5-axis IBIS — 5 stops | |
| Burst Rate | 10fps with AF/AE tracking | 10fps mechanical, 10fps electronic | |
| Battery Life | ~650 shots (CIPA) | ~640 shots (CIPA) | ↓ |
| Weight | 650g body only | 715g body only (with XLR handle) | ↓ |
| Weather Sealed | Yes | Yes | |
| Viewfinder | EVF, 3.69M dots, 0.78× magnification | None — monitor/external EVF use only | |
| Screen | 3.0" touchscreen, tilting | 3.0" touchscreen, fully articulating | |
| Mount | Sony FE mount (full-frame E-mount) | Sony FE mount (full-frame E-mount) | |
| Memory Cards | Dual SD slots (one UHS-II) | Dual CFexpress Type A / SD UHS-II slots |
Compare side-by-side
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