Canon EOS 90Dvs Pentax K-3 Mark IIIvs A7S III

GearFrame · Updated March 2026

Canon Canon EOS 90D Canon Canon EOS 90D (2019) From £849 Best for Sports, wildlife & DSLR enthusiasts View Canon EOS 90D
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
Sony A7S III Sony A7S III (2020) From £2999 Best for Professional video & low-light filmmaking View A7S III

Which should you buy?

Sports, Wildlife & Dslr Enthusiasts — Canon EOS 90D (2019): The best APS-C DSLR Canon ever made — 32MP, 10fps, weather sealing, and an optical viewfinder experience no mirrorless can replicate.

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.

Professional Video & Low-Light Filmmaking — A7S III (2020): If video is your primary discipline, the A7S III is the camera. 4K/120p at 10-bit in a weather-sealed body with a 9.44M dot EVF is an extraordinary package. The 12MP sensor isn't limiting for video — and it's usable at ISO 409,600 in a pinch.

↓ Full specifications below

Canon EOS 90D (2019)

  • You're invested in Canon EF DSLR lenses and don't want to switch systems
  • You shoot wildlife or sports and prefer an optical viewfinder
  • You want a mid-range DSLR upgrade without going mirrorless

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

A7S III (2020)

  • Filmmakers and videographers who need 4K/120p at 10-bit
  • Event videographers who shoot in dark venues regularly
  • Documentary filmmakers who need reliable AF and weather sealing
  • Hybrid shooters where video is primary and stills are secondary

Quick take: The canon eos 90d has the highest resolution at 32mp; the canon eos 90d is the most affordable. Scroll down for the full spec breakdown.

Full specifications

Specification Canon EOS 90D (2019)Pentax K-3 Mark III (2021)A7S III (2020)
Price £849 £1,699 £2,999
Sensor 32.5MP APS-C CMOS (Dual Pixel AF) 25.7MP APS-C BSI CMOS (AA-filterless) 12.1MP Full-Frame BSI CMOS (12-bit, back-illuminated)
Resolution 32.5MP 25.7MP 12.1MP
Video 4K/30p (1.6× crop), FHD/120p 4K/30p, 1080p/60p 4K/120p 10-bit, 4K/60p 10-bit S-Cinetone/S-Log3, 1080p/240p
Autofocus Dual Pixel CMOS AF (live view), 45-point phase-detect (OVF) SAFOX 13 phase-detect, 101-point (25 cross-type) Phase-detect, 759 points, real-time Eye AF (human & animal), subject recognition
Stabilisation None (no IBIS) 5.5-stop 5-axis IBIS (Shake Reduction III) 5.5-stop IBIS
Burst Rate 10fps mechanical 12fps 10fps mechanical
Battery Life ~1300 shots (CIPA with OVF) 800 shots (CIPA) ~600 shots (CIPA) / ~70min continuous 4K recording
Weight 701g body only 820g body only 699g (body, battery, card)
Dimensions 140.7 × 104.8 × 76.8mm 134.5 × 103.5 × 73.5mm 128.9 × 96.9 × 80.8mm
Weather Sealed Yes Yes Yes
Viewfinder Optical pentaprism, 100% coverage, 0.95× magnification Optical pentaprism, 100% coverage, 1.05× magnification OLED EVF, 9.44M dots, 0.90× magnification — best EVF Sony has made
Screen 3.0" vari-angle touchscreen 3.2" tilting touchscreen 3.0" vari-angle touchscreen, 1.44M dots
Mount Canon EF / EF-S Pentax KF-mount Sony E-mount
Memory Cards Dual SD UHS-II slots Dual SD UHS-II Dual CFexpress Type A / SD UHS-II (both slots)
Connectivity USB 2.0, Bluetooth, Wi-Fi USB-C, Wi-Fi, Bluetooth USB-C (USB 3.2 Gen 2), full-size HDMI, Wi-Fi 6, Bluetooth
⚡ Compare specs side by side Canon EOS 90D prices → Pentax K-3 Mark III prices → A7S III prices →

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