A6400vs A7S II
Sony
A7S II (2015)
Starting from £799 new
Best for Low-light video, documentary & available-light filmmaking
View A7S II
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.
Low-Light Video, Documentary & Available-Light Filmmaking — A7S II (2015): A landmark in mirrorless history — the first Sony with IBIS and internal 4K, its low-light video capability still impresses today at a used-market price.
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
A7S II (2015)
- Filmmakers and videographers who want legendary low-light performance at a used-price discount
- Documentary shooters working in unpredictable available light conditions
- A7S III shooters who want a second Sony FE body for backup or B-camera use
- Budget-conscious video producers who want full-frame 4K with S-Log at an accessible price
Quick take: The a6400 has the highest resolution at 24mp; the a7s ii is the most affordable; only the a7s ii is weather sealed. Scroll down for the full spec breakdown.
Full specifications
| Specification | A6400 (2019) | A7S II (2015) |
|---|---|---|
| Price | £899 | £799 |
| Sensor | 24.2MP APS-C Exmor CMOS BSI | 12.1MP full-frame BSI Exmor CMOS |
| Resolution | 24.2MP | 12.1MP |
| Video | 4K/30p (6K oversampled, no crop), 1080p/120p slow-motion | 4K/30p internal (full sensor readout), 1080p/120p, S-Log2/S-Log3 |
| Autofocus | Phase-detect, 425 points, real-time Eye AF & animal AF | 169 phase-detect + 25 contrast AF — limited by modern standards |
| Stabilisation | None (no IBIS) | 5-axis IBIS — 4.5 stops (first Sony mirrorless with IBIS) |
| Burst Rate | 11fps mechanical, 8fps with AF tracking | 5fps continuous |
| Battery Life | ~410 shots (CIPA) | ~370 shots (CIPA) |
| Weight | 403g (body, battery, card) | 584g body only |
| Dimensions | 120.0 × 66.9 × 59.7mm | 126.9 × 95.7 × 60.3mm |
| Weather Sealed | No | Yes |
| Viewfinder | EVF, 2.36M dots, 0.70× magnification | EVF, 2.36M dots, 0.71× magnification |
| Screen | 3.0" tilting touchscreen, 180° flip for selfie/vlog, 921k dots | 3.0" tilting LCD, 1.23M dots |
| Mount | Sony E-mount | Sony FE mount (full-frame E-mount) |
| Memory Cards | Single SD UHS-I | Dual SD UHS-I slots |
| Connectivity | Micro-USB, Wi-Fi, Bluetooth, NFC | USB Micro-B, Bluetooth (via app), Wi-Fi, 3.5mm mic jack |
Suitability by genre
| Genre | A6400 | A7S II |
|---|---|---|
| Video | — | |
| Street | ||
| Portrait | ||
| Travel | — | |
| Wildlife | — | |
| Vlogging & Video | — | |
| Low Light | — | |
| Wedding | — | |
| Sports | — |
More comparisons with A6400
Camera family history