EOS-1D X Mark IIIvs A7S
Canon
EOS-1D X Mark III (2020)
Starting from £3500 new
Best for Professional Sports, Wildlife & Press Photography
View EOS-1D X Mark III
GearScore™ Verdict — Which should you buy?
Professional Sports, Wildlife & Press Photography — EOS-1D X Mark III (2020): Canon's DSLR masterpiece — 20fps live view, 5.5K RAW, 191 cross-type AF points, and dual CFexpress. Almost certainly the finest optical viewfinder camera ever made.
Astrophotography & Low-Light — A7S (2014): The original A7S pioneered the concept of a camera optimised entirely for low light. Its 12.2MP sensor has enormous photosites — extraordinary high-ISO performance that still holds up. Lacking IBIS and limited to 1080p internally (4K requires external recorder), it is a specialist tool. For astrophotography, event videography, or any scenario where light is genuinely scarce, it remains outstanding.
Who should buy what
EOS-1D X Mark III (2020)
- Sports and wildlife photographers with a Canon EF lens collection
- Professionals who prefer the optical viewfinder experience
- Press photographers who need 20fps, weather sealing, and Ethernet
- Canon historians who want to mark the end of the EOS-1D DSLR era
A7S (2014)
- Astrophotographers
- Low-light event videographers
- Filmmakers needing clean high-ISO footage
Quick take: The eos-1d x mark iii has the highest resolution at 20mp; the a7s is the most affordable. Scroll down for the full spec breakdown.
Full specifications
| Specification | EOS-1D X Mark III (2020) | A7S (2014) |
|---|---|---|
| Price | £3,500 | £600 |
| Sensor | 20.1MP full-frame CMOS | 12.2MP Full-Frame BSI CMOS |
| Resolution | 20.1MP | 12.2MP |
| Video | 5.5K RAW, 4K 60fps (crop), 4K 60fps (full-frame via firmware) | 1080p/60p internal, 4K via HDMI (external recorder) |
| Autofocus | 191-point all cross-type OVF AF; 525-point Dual Pixel CMOS AF (Live View) | Phase-detect / contrast-detect hybrid AF |
| Stabilisation | — | None |
| Burst Rate | 16fps mechanical, 20fps live view | 5fps |
| Battery Life | ~2850 shots (CIPA) | ~370 shots (CIPA) |
| Weight | 1250g (body only) | 474g (with battery and card) |
| Dimensions | 158 × 167.6 × 82.6mm | 126.9 × 94.4 × 48.2mm |
| Weather Sealed | Yes | Yes |
| Viewfinder | OVF 0.76× magnification, 100% coverage | Electronic, 2.36M dots, 0.71× magnification |
| Screen | 3.2" fully articulating touchscreen, 4.15M dots | 3.0" tilting LCD, 1.23M dots |
| Mount | Canon EF | Sony FE (full-frame E-mount) |
| Memory Cards | Dual CFexpress Type B slots | Single SD / MemoryStick PRO Duo slot |
| Connectivity | Wi-Fi 5GHz, Bluetooth 4.2, USB-C 3.1 Gen 2, Ethernet | Multi/Micro USB, Wi-Fi, NFC |
Suitability by genre
| Genre | EOS-1D X Mark III | A7S |
|---|---|---|
| Sports & Action | ||
| Wildlife | — | |
| Wedding & Events | — | |
| Portrait | ||
| Vlogging & Video | ||
| Street | ||
| Landscape | ||
| Astrophotography | — | |
| Travel | — |
GearScore™ suitability scores are based on aggregated purchaser reviews weighted by photography genre. See how scores are calculated →
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Camera family history