EOS Rvs Pentax K-3 Mark III
Canon
EOS R (2018)
Starting from £799 new
Best for Entry to full-frame mirrorless & RF lens exploration
View EOS R
VS
Pentax
Pentax K-3 Mark III (2021)
Starting from £1699 new
Best for DSLR enthusiasts & outdoor photographers
View Pentax K-3 Mark III
GearScore™ Verdict — Which should you buy?
Entry To Full-Frame Mirrorless & Rf Lens Exploration — EOS R (2018): The RF mount's founding camera — 30MP, Dual Pixel CMOS AF, and the proof-of-concept that launched Canon's mirrorless era.
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.
Who should buy what
EOS R (2018)
- Canon DSLR users wanting to enter the RF ecosystem at the lowest full-frame price
- EF lens collectors who want an affordable RF body to use with the EF-RF adapter
- Photographers stepping up from APS-C who want full-frame quality on a budget
- RF system fans who want a second body without full EOS R6 pricing
Pentax K-3 Mark III (2021)
- DSLR photographers who want the finest APS-C optical viewfinder experience
- Outdoor and weather photographers who need robust all-weather sealing
- Pentax lens owners who want to use their existing K-mount glass
- Photographers who prefer optical viewfinders and refuse to switch to mirrorless
Quick take: The eos r has the highest resolution at 30mp; the eos r is the most affordable. Scroll down for the full spec breakdown.
Full specifications
| Specification | EOS R (2018) | Pentax K-3 Mark III (2021) |
|---|---|---|
| Price | £799 | £1,699 |
| Sensor | 30.3MP full-frame CMOS | 25.7MP APS-C BSI CMOS (AA-filterless) |
| Resolution | 30.3MP | 25.7MP |
| Video | 4K/30p (1.7× crop), 1080p/60p | 4K/30p, 1080p/60p |
| Autofocus | Dual Pixel CMOS AF — 5655 AF areas, Eye AF | SAFOX 13 phase-detect, 101-point (25 cross-type) |
| Stabilisation | None | 5.5-stop 5-axis IBIS (Shake Reduction III) |
| Burst Rate | 8fps continuous (5fps with AF/AE) | 12fps |
| Battery Life | ~350 shots (CIPA) | 800 shots (CIPA) |
| Weight | 660g body only | 820g body only |
| Dimensions | 135.8 × 98.3 × 84.4mm | 134.5 × 103.5 × 73.5mm |
| Weather Sealed | Yes | Yes |
| Viewfinder | EVF, 3.69M dots, 0.71× magnification | Optical pentaprism, 100% coverage, 1.05× magnification |
| Screen | 3.0" touchscreen, tilting | 3.2" tilting touchscreen |
| Mount | Canon RF mount (full-frame) | Pentax KF-mount |
| Memory Cards | Single SD UHS-II slot | Dual SD UHS-II |
| Connectivity | USB-C, Bluetooth, Wi-Fi, 3.5mm mic jack | USB-C, Wi-Fi, Bluetooth |
Suitability by genre
| Genre | EOS R | Pentax K-3 Mark III |
|---|---|---|
| Portrait | ||
| Landscape | ||
| Travel | ||
| Wedding | — | |
| Vlogging & Video | ||
| Sports | — | |
| Wildlife | — | |
| Sports & Action | — |
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