X-A7vs OM System OM-1 Mark IIvs Pentax K-3 Mark III
OM System
OM System OM-1 Mark II (2024)
From £1999
Best for Wildlife, birds & outdoor sports
View OM System OM-1 Mark II
Pentax
Pentax K-3 Mark III (2021)
From £1699
Best for DSLR enthusiasts & outdoor photographers
View Pentax K-3 Mark III
Which should you buy?
Beginner Fujifilm — X-A7 (2019): The most affordable X-mount entry — Fujifilm colour and film simulations with a large flip screen for beginners.
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.
Dslr Enthusiasts & Outdoor Photographers — Pentax K-3 Mark III (2021): The finest APS-C DSLR ever made — class-leading weather sealing, optical viewfinder, 5-axis IBIS, and extraordinary build for photographers committed to DSLR.
Who should buy what
X-A7 (2019)
- You want an affordable first mirrorless with decent video capabilities
- You shoot a lot of selfie-style content or vlog on a budget
- Note: no viewfinder and limited lens support — the X-T30 II is a better long-term investment
OM System OM-1 Mark II (2024)
- You shoot wildlife, birds in flight, or fast-moving action where tracking accuracy is critical
- You need extreme weather sealing for shooting in rain, dust, mud, or freezing cold
- You're invested in the MFT ecosystem and want the absolute best body available
Pentax K-3 Mark III (2021)
- You're a committed DSLR photographer with significant investment in Pentax glass
- You shoot in extreme weather conditions and place build quality and reliability above everything
- You prefer optical viewfinder performance and want the best modern APS-C DSLR available
Quick take: The pentax k-3 mark iii has the highest resolution at 26mp; the x-a7 is the most affordable; only the om system om-1 mark ii, pentax k-3 mark iii are weather sealed. Scroll down for the full spec breakdown.
Full specifications
| Specification | X-A7 (2019) | OM System OM-1 Mark II (2024) | Pentax K-3 Mark III (2021) |
|---|---|---|---|
| Price | £399 | £1,999 | £1,699 |
| Sensor | 24.2MP APS-C CMOS (Bayer, not X-Trans) | 20MP Micro Four Thirds Live MOS | 25.7MP APS-C BSI CMOS (AA-filterless) |
| Resolution | 24.2MP | 20.0MP | 25.7MP |
| Video | 4K/30p, 1080p/60p | 4K/60p, 1080p/240p, 4K HLG | 4K/30p, 1080p/60p |
| Autofocus | Phase-detect + contrast, 425 points | AI subject detection AF (birds, animals, motorsport) | SAFOX 13 phase-detect, 101-point (25 cross-type) |
| Stabilisation | None (no IBIS) | 8.5-stop IBIS | 5.5-stop 5-axis IBIS (Shake Reduction III) |
| Burst Rate | 6fps | 120fps with AF tracking | 12fps |
| Battery Life | ~440 shots (CIPA) | 520 shots (CIPA) | 800 shots (CIPA) |
| Weight | 320g body only | 599g body only | 820g body only |
| Dimensions | 118.0 × 80.6 × 55.2mm | 134.8 × 91.6 × 72.7mm | 134.5 × 103.5 × 73.5mm |
| Weather Sealed | No | Yes | Yes |
| Viewfinder | None | 0.83" OLED EVF, 5.76M dots, 120fps | Optical pentaprism, 100% coverage, 1.05× magnification |
| Screen | 3.5" fully articulating touchscreen | 3.0" fully articulating touchscreen | 3.2" tilting touchscreen |
| Mount | Fujifilm X-mount | Micro Four Thirds | Pentax KF-mount |
| Memory Cards | Single SD UHS-I slot | Dual SD UHS-II | Dual SD UHS-II |
| Connectivity | USB Micro-B, Bluetooth, Wi-Fi, micro HDMI | USB-C, Wi-Fi, Bluetooth | USB-C, Wi-Fi, Bluetooth |
Compare pairs from this group