Upgrade Guide
Sony A6400→Sony FX3
Is it worth upgrading? Spec analysis, key improvements, and our verdict.
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Worthwhile
Clear improvements over the A6400. Whether it justifies the cost depends on which upgrades matter most to your shooting.
What's new in the FX3
-
Weather sealingAdded — fully sealed body
-
Battery life~640 shots (CIPA) vs ~410 shots (CIPA)
-
Generation2 years newer (2021 vs 2019)
Unchanged or similar
-
Resolution12MP (down from 24MP — optimised for low light)
Suitability by genre
| Genre | A6400 | FX3 | |
|---|---|---|---|
| Video | — | ||
| Street | -5.0 | ||
| Portrait | -2.0 | ||
| Travel | -3.0 | ||
| Wildlife | — | ||
| Vlogging & Video | — | ||
| Low Light | — | ||
| Wedding | — |
Full spec comparison
| Spec | A6400 | FX3 | |
|---|---|---|---|
| Price | £899 | £3,799 | |
| Released | 2019 | 2021 | ↑ |
| Sensor | 24.2MP APS-C Exmor CMOS BSI | 12.1MP full-frame BSI Exmor R CMOS (same as A7S III) | |
| Resolution | 24MP | 12MP | ↓ |
| Video | 4K/30p (6K oversampled, no crop), 1080p/120p slow-motion | 4K/120p, 4K/60p 10-bit, 12-bit RAW output, S-Log3, S-Cinetone | |
| Autofocus | Phase-detect, 425 points, real-time Eye AF & animal AF | Real-time tracking with subject recognition (human, animal) | |
| Stabilisation | None (no IBIS) | 5-axis IBIS — 5 stops | |
| Burst Rate | 11fps mechanical, 8fps with AF tracking | 10fps mechanical, 10fps electronic | ↓ |
| Battery Life | ~410 shots (CIPA) | ~640 shots (CIPA) | ↑ |
| Weight | 403g (body, battery, card) | 715g body only (with XLR handle) | ↓ |
| Weather Sealed | No | Yes | ↑ |
| Viewfinder | EVF, 2.36M dots, 0.70× magnification | None — monitor/external EVF use only | |
| Screen | 3.0" tilting touchscreen, 180° flip for selfie/vlog, 921k dots | 3.0" touchscreen, fully articulating | |
| Mount | Sony E-mount | Sony FE mount (full-frame E-mount) | |
| Memory Cards | Single SD UHS-I | Dual CFexpress Type A / SD UHS-II slots |
Compare side-by-side
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