A6400vs FX3
Sony
FX3 (2021)
Starting from £3799 new
Best for Professional video, documentary & cinematic filmmaking
View FX3
GearScore™ Verdict — Which should you buy?
Content Creation & Vlogging — A6400 (2019): The best value APS-C Sony you can buy — especially used. Real-time Eye AF at this price point was transformative when it launched and still makes it one of the most reliable autofocus systems in the lineup.
Professional Video, Documentary & Cinematic Filmmaking — FX3 (2021): The definitive run-and-gun cinema camera — A7S III sensor quality in a body built specifically for video professionals.
Who should buy what
A6400 (2019)
- Vloggers and content creators who need a flip screen and reliable AF
- Photographers upgrading from a compact or smartphone
- Beginners who want room to grow into a full E-mount lens ecosystem
- Anyone prioritising autofocus performance at an accessible price
FX3 (2021)
- Professional videographers and filmmakers who need cinema-quality colour science in a compact body
- Documentary and run-and-gun shooters who need 4K/120p and built-in XLR audio
- Sony A7S III owners who want a purpose-built video body alongside their stills camera
- Gimbal and drone operators who need a compact full-frame cinema camera
Quick take: The a6400 has the highest resolution at 24mp; the a6400 is the most affordable; only the fx3 is weather sealed. Scroll down for the full spec breakdown.
Full specifications
| Specification | A6400 (2019) | FX3 (2021) |
|---|---|---|
| Price | £899 | £3,799 |
| Sensor | 24.2MP APS-C Exmor CMOS BSI | 12.1MP full-frame BSI Exmor R CMOS (same as A7S III) |
| Resolution | 24.2MP | 12.1MP |
| 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) |
| Dimensions | 120.0 × 66.9 × 59.7mm | 129.7 × 78.0 × 84.5mm |
| 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 |
| Connectivity | Micro-USB, Wi-Fi, Bluetooth, NFC | USB-C (10Gbps), full-size HDMI, XLR via handle, Bluetooth, Wi-Fi |
Suitability by genre
| Genre | A6400 | FX3 |
|---|---|---|
| Video | — | |
| Street | ||
| Portrait | ||
| Travel | ||
| Wildlife | — | |
| Vlogging & Video | — | |
| Low Light | — | |
| Wedding | — |
More comparisons with A6400
Camera family history