OM System OM-1 Mark IIvs A7S
OM System
OM System OM-1 Mark II (2024)
Starting from £1999 new
Best for Wildlife, birds & outdoor sports
View OM System OM-1 Mark II
GearScore™ Verdict — Which should you buy?
Wildlife, Birds & Outdoor Sports — OM System OM-1 Mark II (2024): OM System's most capable camera — 120fps AF burst, AI subject detection, and IP53 weather sealing make it the best-value pro wildlife camera.
Astrophotography & Low-Light — A7S (2014): The original A7S pioneered the concept of a camera optimised entirely for low light. Its 12.2MP sensor has enormous photosites — extraordinary high-ISO performance that still holds up. Lacking IBIS and limited to 1080p internally (4K requires external recorder), it is a specialist tool. For astrophotography, event videography, or any scenario where light is genuinely scarce, it remains outstanding.
Who should buy what
OM System OM-1 Mark II (2024)
- Wildlife and bird photographers who need the best subject tracking in MFT
- Sports photographers who want weather sealing and 50fps burst
- OM-1 owners looking for a meaningful autofocus upgrade
- Professionals who need pro-grade weather sealing in the lightest possible system
A7S (2014)
- Astrophotographers
- Low-light event videographers
- Filmmakers needing clean high-ISO footage
Quick take: The om system om-1 mark ii has the highest resolution at 20mp; the a7s is the most affordable. Scroll down for the full spec breakdown.
Full specifications
| Specification | OM System OM-1 Mark II (2024) | A7S (2014) |
|---|---|---|
| Price | £1,999 | £600 |
| Sensor | 20MP Micro Four Thirds Live MOS | 12.2MP Full-Frame BSI CMOS |
| Resolution | 20.0MP | 12.2MP |
| Video | 4K/60p, 1080p/240p, 4K HLG | 1080p/60p internal, 4K via HDMI (external recorder) |
| Autofocus | AI subject detection AF (birds, animals, motorsport) | Phase-detect / contrast-detect hybrid AF |
| Stabilisation | 8.5-stop IBIS | None |
| Burst Rate | 120fps with AF tracking | 5fps |
| Battery Life | 520 shots (CIPA) | ~370 shots (CIPA) |
| Weight | 599g body only | 474g (with battery and card) |
| Dimensions | 134.8 × 91.6 × 72.7mm | 126.9 × 94.4 × 48.2mm |
| Weather Sealed | Yes | Yes |
| Viewfinder | 0.83" OLED EVF, 5.76M dots, 120fps | Electronic, 2.36M dots, 0.71× magnification |
| Screen | 3.0" fully articulating touchscreen | 3.0" tilting LCD, 1.23M dots |
| Mount | Micro Four Thirds | Sony FE (full-frame E-mount) |
| Memory Cards | Dual SD UHS-II | Single SD / MemoryStick PRO Duo slot |
| Connectivity | USB-C, Wi-Fi, Bluetooth | Multi/Micro USB, Wi-Fi, NFC |
Suitability by genre
| Genre | OM System OM-1 Mark II | A7S |
|---|---|---|
| Wildlife | — | |
| Sports & Action | ||
| Landscape | ||
| Travel | ||
| Portrait | ||
| Vlogging & Video | ||
| Astrophotography | — | |
| Street | — |
GearScore™ suitability scores are based on aggregated purchaser reviews weighted by photography genre. See how scores are calculated →
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