OM System OM-1 Mark IIvs Pentax K-3 Mark III

GearFrame · Updated March 2026

OM System OM System OM-1 Mark II OM System OM System OM-1 Mark II (2024) From £1999 Best for Wildlife, birds & outdoor sports View OM System OM-1 Mark 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?

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.

↓ Full specifications below

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 pentax k-3 mark iii is the most affordable. Scroll down for the full spec breakdown.

Full specifications

Specification OM System OM-1 Mark II (2024)Pentax K-3 Mark III (2021)
Price £1,999 £1,699
Sensor 20MP Micro Four Thirds Live MOS 25.7MP APS-C BSI CMOS (AA-filterless)
Resolution 20.0MP 25.7MP
Video 4K/60p, 1080p/240p, 4K HLG 4K/30p, 1080p/60p
Autofocus AI subject detection AF (birds, animals, motorsport) SAFOX 13 phase-detect, 101-point (25 cross-type)
Stabilisation 8.5-stop IBIS 5.5-stop 5-axis IBIS (Shake Reduction III)
Burst Rate 120fps with AF tracking 12fps
Battery Life 520 shots (CIPA) 800 shots (CIPA)
Weight 599g body only 820g body only
Dimensions 134.8 × 91.6 × 72.7mm 134.5 × 103.5 × 73.5mm
Weather Sealed Yes Yes
Viewfinder 0.83" OLED EVF, 5.76M dots, 120fps Optical pentaprism, 100% coverage, 1.05× magnification
Screen 3.0" fully articulating touchscreen 3.2" tilting touchscreen
Mount Micro Four Thirds Pentax KF-mount
Memory Cards Dual SD UHS-II Dual SD UHS-II
Connectivity USB-C, Wi-Fi, Bluetooth USB-C, Wi-Fi, Bluetooth
⚡ Compare specs side by side OM System OM-1 Mark II prices → Pentax K-3 Mark III prices →

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