EOS R50vs Pentax K-3 Mark IIIvs Sigma fp

GearFrame · Updated March 2026

Canon EOS R50 Canon EOS R50 (2023) From £599 Best for Beginners & family View EOS R50
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?

Beginners & Family — EOS R50 (2023): Canon's most beginner-friendly RF body — Dual Pixel AF and beautiful colour science in an approachable package.

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 R50 (2023)

  • You're completely new to mirrorless cameras and want something uncomplicated
  • You create vertical content for TikTok, Instagram Reels, or YouTube Shorts
  • You want great autofocus without needing to understand complex menus

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 eos r50 is the most affordable; only the pentax k-3 mark iii is weather sealed. Scroll down for the full spec breakdown.

Full specifications

Specification EOS R50 (2023)Pentax K-3 Mark III (2021)Sigma fp (2019)
Price £599 £1,699 £1,499
Sensor 24.2MP APS-C CMOS 25.7MP APS-C BSI CMOS (AA-filterless) 24.6MP full-frame Bayer CMOS
Resolution 24.2MP 25.7MP 24.6MP
Video 4K/30p (uncropped 4K/24p), FHD/60p 4K/30p, 1080p/60p 12-bit Cinema DNG RAW, 4K/24p, 1080p/120p
Autofocus Dual Pixel CMOS AF II, face/eye/subject tracking SAFOX 13 phase-detect, 101-point (25 cross-type) Contrast-detect AF with face/eye detection
Stabilisation None (no IBIS) 5.5-stop 5-axis IBIS (Shake Reduction III) None (lens-based only)
Burst Rate 12fps mechanical, 15fps electronic 12fps 18fps electronic
Battery Life ~380 shots (CIPA) 800 shots (CIPA) 200 shots (CIPA)
Weight 375g body only 820g body only 422g body only
Dimensions 116.3 × 85.5 × 68.8mm 134.5 × 103.5 × 73.5mm 112.6 × 69.9 × 45.3mm
Weather Sealed No Yes No
Viewfinder EVF, 2.36M dots Optical pentaprism, 100% coverage, 1.05× magnification None
Screen 3.0" vari-angle touchscreen 3.2" tilting touchscreen 3.15" fixed touchscreen
Mount Canon RF-S / RF Pentax KF-mount Leica L-mount
Memory Cards Single SD UHS-II slot Dual SD UHS-II Single SD UHS-II + CFexpress Type B (via adapter)
Connectivity USB-C, Bluetooth, Wi-Fi USB-C, Wi-Fi, Bluetooth USB-C 3.1, Wi-Fi, Bluetooth
⚡ Compare specs side by side EOS R50 prices → Pentax K-3 Mark III prices → Sigma fp prices →

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