EOS R6 Mark IIvs Pentax K-3 Mark IIIvs Sigma fp

GearFrame · Updated March 2026

Canon EOS R6 Mark II Canon EOS R6 Mark II (2022) From £2099 Best for Portraits & action View EOS R6 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
VS
Sigma Sigma fp Sigma Sigma fp (2019) From £1499 Best for Creative filmmakers & experimental photographers View Sigma fp

Which should you buy?

Portraits & Action — EOS R6 Mark II (2022): 40fps burst, 8-stop IBIS, and Canon's best-in-class Dual Pixel AF — exceptional for action, sports, and portrait work.

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.

Creative Filmmakers & Experimental Photographers — Sigma fp (2019): The smallest full-frame camera in the world — Cinema DNG RAW and L-mount flexibility in a pocket-sized body that rewards creative shooters.

↓ Full specifications below

EOS R6 Mark II (2022)

  • You want a do-everything full-frame body for weddings and events
  • You need reliable subject tracking across stills and fast-moving video
  • You shoot both photos and video professionally and need a single body that handles both
  • You want Canon's colour science with a modern mirrorless system

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

Sigma fp (2019)

  • You're a filmmaker building a cinema rig where the smallest full-frame body is essential
  • You want L-mount compatibility to pair with Sigma Art or Leica SL lenses
  • You prioritise video and cinema colour over stills ergonomics and functionality

Quick take: The pentax k-3 mark iii has the highest resolution at 26mp; the sigma fp is the most affordable; only the eos r6 mark ii, pentax k-3 mark iii are weather sealed. Scroll down for the full spec breakdown.

Full specifications

Specification EOS R6 Mark II (2022)Pentax K-3 Mark III (2021)Sigma fp (2019)
Price £2,099 £1,699 £1,499
Sensor 24.2MP Full-frame BSI CMOS 25.7MP APS-C BSI CMOS (AA-filterless) 24.6MP full-frame Bayer CMOS
Resolution 24.2MP 25.7MP 24.6MP
Video 4K/60p 10-bit oversampled, 6K RAW out, FHD/180p 4K/30p, 1080p/60p 12-bit Cinema DNG RAW, 4K/24p, 1080p/120p
Autofocus Dual Pixel CMOS AF II, 6072 zones, deep-learning subject tracking SAFOX 13 phase-detect, 101-point (25 cross-type) Contrast-detect AF with face/eye detection
Stabilisation 5-axis IBIS, 8.0 stops (coordinated with IS lenses) 5.5-stop 5-axis IBIS (Shake Reduction III) None (lens-based only)
Burst Rate 12fps mechanical, 40fps electronic 12fps 18fps electronic
Battery Life ~760 shots (CIPA) 800 shots (CIPA) 200 shots (CIPA)
Weight 670g body only 820g body only 422g body only
Dimensions 138.4 × 98.4 × 88.4mm 134.5 × 103.5 × 73.5mm 112.6 × 69.9 × 45.3mm
Weather Sealed Yes Yes No
Viewfinder EVF, 3.69M dots, 0.76× magnification Optical pentaprism, 100% coverage, 1.05× magnification None
Screen 3.0" fully articulating touchscreen 3.2" tilting touchscreen 3.15" fixed touchscreen
Mount Canon RF mount (full-frame) Pentax KF-mount Leica L-mount
Memory Cards Dual SD UHS-II slots Dual SD UHS-II Single SD UHS-II + CFexpress Type B (via adapter)
Connectivity USB-C 3.1, Bluetooth, Wi-Fi USB-C, Wi-Fi, Bluetooth USB-C 3.1, Wi-Fi, Bluetooth
⚡ Compare specs side by side EOS R6 Mark II prices → Pentax K-3 Mark III prices → Sigma fp prices →

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