A7S IIvs A9
Sony
A7S II (2015)
Starting from £799 new
Best for Low-light video, documentary & available-light filmmaking
View A7S II
Sony
A9 (2017)
Starting from £1999 new
Best for Professional sports, wildlife & action photography
View A9
GearScore™ Verdict — Which should you buy?
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.
Professional Sports, Wildlife & Action Photography — A9 (2017): The camera that changed professional photography — the A9's 20fps blackout-free burst and silent shutter proved mirrorless had definitively surpassed the DSLR.
Who should buy what
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
A9 (2017)
- Sports photographers who want the original 20fps mirrorless at a lower used price than the A9 II
- Wildlife photographers who need blackout-free burst with fast, reliable tracking
- Sony FE system users who want a professional sports body
- Photographers interested in the camera that changed the industry
Quick take: The a9 has the highest resolution at 24mp; the a7s ii is the most affordable. Scroll down for the full spec breakdown.
Full specifications
| Specification | A7S II (2015) | A9 (2017) |
|---|---|---|
| Price | £799 | £1,999 |
| Sensor | 12.1MP full-frame BSI Exmor CMOS | 24.2MP Full-Frame Stacked BSI CMOS Exmor RS |
| Resolution | 12.1MP | 24.2MP |
| Video | 4K/30p internal (full sensor readout), 1080p/120p, S-Log2/S-Log3 | 4K/30p, 1080p/120p |
| Autofocus | 169 phase-detect + 25 contrast AF — limited by modern standards | 693 phase-detect + 25 contrast-detect, real-time eye/body tracking |
| Stabilisation | 5-axis IBIS — 4.5 stops (first Sony mirrorless with IBIS) | IBIS — 5-axis, up to 5 stops |
| Burst Rate | 5fps continuous | 20fps (blackout-free, silent electronic shutter with full AF/AE) |
| Battery Life | ~370 shots (CIPA) | ~650 shots (CIPA) |
| Weight | 584g body only | 673g (with battery and card) |
| Dimensions | 126.9 × 95.7 × 60.3mm | 126.9 × 95.6 × 63.0mm |
| Weather Sealed | Yes | Yes |
| Viewfinder | EVF, 2.36M dots, 0.71× magnification | EVF, OLED 3.69M dots, 0.78× magnification, 60fps refresh (blackout-free) |
| Screen | 3.0" tilting LCD, 1.23M dots | 3.0" tilting touchscreen |
| Mount | Sony FE mount (full-frame E-mount) | Sony FE (full-frame E-mount) |
| Memory Cards | Dual SD UHS-I slots | Dual SD UHS-II slots |
| Connectivity | USB Micro-B, Bluetooth (via app), Wi-Fi, 3.5mm mic jack | USB, Wi-Fi 5GHz, Bluetooth, HDMI |
Suitability by genre
| Genre | A7S II | A9 |
|---|---|---|
| Vlogging & Video | ||
| Low Light | — | |
| Wedding | — | |
| Portrait | ||
| Street | — | |
| Sports | — | |
| Sports & Action | — | |
| Wildlife | — | |
| Wedding & Events | — | |
| Travel | — |
GearScore™ suitability scores are based on aggregated purchaser reviews weighted by photography genre. See how scores are calculated →
More comparisons with A7S II
Camera family history