OM-3vs A7 III
OM System
OM-3 (2024)
Starting from £999 new
Best for Travel, outdoor & adventure photography
View OM-3
GearScore™ Verdict — Which should you buy?
Travel, Outdoor & Adventure Photography — OM-3 (2024): The ideal mid-range OM System camera — weather sealed, class-leading IBIS, and superb computational features in a compact body.
All-Round Photography & Video — A7 III (2018): Still one of the best all-round cameras money can buy — particularly strong used. The A7 III proved that full-frame doesn't have to mean compromises, and nothing at this price point has meaningfully beaten it.
Who should buy what
OM-3 (2024)
- Outdoor and adventure photographers who need weather sealing and compact size
- Wildlife and bird photographers wanting improved AF over the OM-5
- Travel shooters who want a rugged, lightweight MFT system
- OM-5 or E-M5 III owners wanting better autofocus without going to the OM-1
A7 III (2018)
- Enthusiast photographers upgrading from APS-C for the first time
- Working photographers who need reliable AF and weather sealing
- Anyone who shoots in low light regularly
- Hybrid shooters needing both stills and video performance
Quick take: The a7 iii has the highest resolution at 24mp; the om-3 is the most affordable. Scroll down for the full spec breakdown.
Full specifications
| Specification | OM-3 (2024) | A7 III (2018) |
|---|---|---|
| Price | £999 | £1,699 |
| Sensor | 20.4MP Live MOS Micro Four Thirds | 24.2MP Full-Frame Exmor R BSI CMOS |
| Resolution | 20.4MP | 24.2MP |
| Video | 4K/60p (10-bit), C4K/30p, 1080p/120p | 4K/30p (6K oversampled), 1080p/120p slow-motion |
| Autofocus | Phase-detect AF — subject recognition (human, animal, bird, vehicle) | Phase-detect, 693 points, real-time Eye AF & animal AF |
| Stabilisation | IBIS — up to 6.5 stops (7.5 stops with Sync IS lenses) | 5-axis IBIS, 5 stops |
| Burst Rate | 10fps mechanical, 30fps electronic with AF | 10fps with AF/AE tracking |
| Battery Life | ~400 shots (CIPA) | ~710 shots (CIPA) |
| Weight | 414g (with battery) | 565g (body, battery, card) |
| Dimensions | 122.3 × 84.6 × 49.4mm | 126.9 × 95.6 × 73.7mm |
| Weather Sealed | Yes | Yes |
| Viewfinder | EVF, 2.36M dots, 0.74× magnification | EVF, 2.36M dots, 0.78× magnification |
| Screen | 3.0" fully articulating touchscreen | 3.0" tilting touchscreen, 921k dots |
| Mount | Micro Four Thirds | Sony E-mount |
| Memory Cards | Single SD UHS-II slot | Dual SD (UHS-II slot 1, UHS-I slot 2) |
| Connectivity | USB-C, Wi-Fi, Bluetooth | USB-C (USB 3.2), Wi-Fi, Bluetooth, NFC |
Suitability by genre
| Genre | OM-3 | A7 III |
|---|---|---|
| Travel | ||
| Wildlife | ||
| Landscape | — | |
| Street | ||
| Portrait | ||
| Vlogging & Video | — | |
| Video | — |
More comparisons with OM-3
Camera family history