Canon EOS R3vs Olympus OM-D E-M5 IIIvs A7 IV

GearFrame · Updated March 2026

Canon Canon EOS R3 Canon Canon EOS R3 (2021) From £5999 Best for Sports & photojournalism professionals View Canon EOS R3
VS
OM System Olympus OM-D E-M5 III OM System Olympus OM-D E-M5 III (2019) From £699 Best for Travel & lightweight outdoor photography View Olympus OM-D E-M5 III
VS
Sony A7 IV Sony A7 IV (2021) From £2299 Best for Portrait & wedding photography View A7 IV

Which should you buy?

Sports & Photojournalism Professionals — Canon EOS R3 (2021): The pinnacle of Canon's mirrorless lineup for speed — Eye Control AF and 30fps burst in the most rugged body Canon has ever produced.

Travel & Lightweight Outdoor Photography — Olympus OM-D E-M5 III (2019): The lightest weather-sealed MFT camera — compact, travel-friendly, and capable with 7.5-stop IBIS in a body that fits in a jacket pocket.

Portrait & Wedding Photography — A7 IV (2021): The full-frame portrait benchmark — 33MP, AI Eye AF, and exceptional skin-tone rendering in a pro-grade hybrid body.

↓ Full specifications below

Canon EOS R3 (2021)

  • You shoot sport, motorsport, wildlife, or news at a professional level
  • You need Canon's most reliable and fastest autofocus available
  • You need extreme weather sealing for demanding shooting conditions

Olympus OM-D E-M5 III (2019)

  • You want a lightweight, sealed camera for travel and outdoor photography
  • You're new to Micro Four Thirds and want a capable mid-range body with excellent stabilisation
  • Note: consider the newer OM-5 for updated specs in a similar compact form factor

A7 IV (2021)

  • You want a high-resolution full-frame all-rounder for portraits, weddings, or travel
  • You're stepping up from APS-C or a DSLR and want the best all-round full-frame body under £3,000
  • You shoot a mix of stills and video and need a single body that handles both seriously
  • You want access to the widest lens ecosystem in the mirrorless market

Quick take: The a7 iv has the highest resolution at 33mp; the olympus om-d e-m5 iii is the most affordable. Scroll down for the full spec breakdown.

Full specifications

Specification Canon EOS R3 (2021)Olympus OM-D E-M5 III (2019)A7 IV (2021)
Price £5,999 £699 £2,299
Sensor 24.1MP full-frame BSI stacked CMOS 20.4MP Micro Four Thirds Live MOS 33MP Full-frame BSI Exmor R CMOS
Resolution 24.1MP 20.4MP 33.0MP
Video 6K RAW, 4K/120p, 1080p/180p 4K/30p, 1080p/120p 4K/60p oversampled, 10-bit internal, S-Log3, S-Cinetone
Autofocus Dual Pixel CMOS AF II with Eye Control AF Hybrid phase/contrast AF with face/eye detection 759-point phase-detect, AI subject recognition
Stabilisation 8-stop IBIS 7.5-stop 5-axis IBIS 5-axis IBIS, 5.5 stops
Burst Rate 30fps electronic / 12fps mechanical 30fps electronic / 10fps mechanical 10fps mechanical, 30fps electronic
Battery Life 620 shots (CIPA) 390 shots (CIPA) ~580 shots (CIPA)
Weight 1015g body only 414g body only 659g body only
Dimensions 150.0 × 142.6 × 87.2mm 125.3 × 85.2 × 49.7mm 131.3 × 96.4 × 79.8mm
Weather Sealed Yes Yes Yes
Viewfinder 0.76" OLED EVF, 5.76M dots, 120fps 0.35" OLED EVF, 2.36M dots EVF, 3.69M dots, 0.78× magnification
Screen 3.2" fully articulating touchscreen 3.0" fully articulating touchscreen 3.0" vari-angle touchscreen
Mount Canon RF Micro Four Thirds Sony FE (full-frame E-mount)
Memory Cards Dual CFexpress Type B Single SD UHS-I Dual slots: CFexpress Type A + SD UHS-II
Connectivity USB-C 3.2, HDMI full-size, Wi-Fi 6, Bluetooth, LAN Micro USB, Wi-Fi, Bluetooth USB-C (3.2 Gen 2), Bluetooth, Wi-Fi
⚡ Compare specs side by side Canon EOS R3 prices → Olympus OM-D E-M5 III prices → A7 IV prices →

Compare pairs from this group