X-A7vs OM-1 IIvs Pentax K-3 Mark III

GearFrame · Updated March 2026

Fujifilm X-A7 Fujifilm X-A7 (2019) From £399 Best for Beginner Fujifilm View X-A7
VS
OM System OM-1 II OM System OM-1 II (2024) From £1499 Best for Wildlife & action View OM-1 II
VS
Pentax Pentax K-3 Mark III 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 & Action — OM-1 II (2024): 120fps burst, 8-stop IBIS, and IP53 sealing — the most capable wildlife and action camera in the Micro Four Thirds world.

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.

↓ Full specifications below

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-1 II (2024)

  • You shoot wildlife, birds, or fast action and want the best MFT autofocus available
  • You need strong weather sealing without the weight of a full-frame sports body
  • You're in the MFT system and want a flagship-level body upgrade

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-1 ii, pentax k-3 mark iii are weather sealed. Scroll down for the full spec breakdown.

Full specifications

Specification X-A7 (2019)OM-1 II (2024)Pentax K-3 Mark III (2021)
Price £399 £1,499 £1,699
Sensor 24.2MP APS-C CMOS (Bayer, not X-Trans) 20.4MP Micro Four Thirds Stacked BSI CMOS 25.7MP APS-C BSI CMOS (AA-filterless)
Resolution 24.2MP 20.4MP 25.7MP
Video 4K/30p, 1080p/60p 4K/120p Cinema4K, Apple ProRes RAW (with recorder) 4K/30p, 1080p/60p
Autofocus Phase-detect + contrast, 425 points Quad-Pixel phase-detect, 1053 points, AI subject recognition (birds/animals) SAFOX 13 phase-detect, 101-point (25 cross-type)
Stabilisation None (no IBIS) 5-axis IBIS, 8.0 stops (Dual IS) 5.5-stop 5-axis IBIS (Shake Reduction III)
Burst Rate 6fps 120fps electronic (blackout-free), 15fps mechanical 12fps
Battery Life ~440 shots (CIPA) ~520 shots (CIPA) 800 shots (CIPA)
Weight 320g body only 561g 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 EVF, 5.76M dots, 0.83× magnification 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 slots Dual SD UHS-II
Connectivity USB Micro-B, Bluetooth, Wi-Fi, micro HDMI USB-C, Bluetooth, Wi-Fi USB-C, Wi-Fi, Bluetooth
⚡ Compare specs side by side X-A7 prices → OM-1 II prices → Pentax K-3 Mark III prices →

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