Canon
EOS-1D X Mark III
Canon flagship DSLR for sports and news with 20fps and legendary reliability.
$6,499
Launch priceReleased Feb 2020
Pentax
645Z
51MP medium format DSLR that made digital MF accessible — still prized for landscape and studio.
$8,499
Launch priceReleased Apr 2014
EOS-1D X Mark III is 5.8 years newer.
Affiliate disclosure: As an Amazon Associate, Cameraegg earns from qualifying purchases. Cameraegg may also earn commission from B&H links, at no extra cost to you.
Wins
EOS-1D X Mark III
Wins
645Z
7 categories tied
Which would you choose?
TL;DR — Key differences
- AEOS-1D X Mark III has higher ISO max (native) (102,400 vs 25,600)
- B645Z has higher Resolution (51.4 MP vs 20.1 MP)
- AEOS-1D X Mark III has lower Weight (720 g vs 1470 g)
- AEOS-1D X Mark III has higher Burst (mechanical) (16 fps vs 8 fps)
- AEOS-1D X Mark III has higher AF points / zones (191 vs 101)
Key specs at a glance
Size and weight, to scale
📸 Snap this size diff to shareEOS-1D X Mark III
138 × 98 × 88 mm
720 g (1.59 lb / 25.40 oz)
Credit card
85.6 × 54 mm
for scale
645Z
156 × 117 × 123 mm
1470 g (3.24 lb / 51.85 oz)
EOS-1D X Mark III is 18mm narrower, 19mm shorter, and 35mm thinner than 645Z.
EOS-1D X Mark III is 750 g lighter than 645Z.
Depth (front-to-back): 88mm EOS-1D X Mark III · 123mm 645Z
Sensor size, to scale
EOS-1D X Mark III
36 × 24 mm · Full Frame
864 mm² area
645Z
43.8 × 32.8 mm · Medium Format
1437 mm² area
1.7× larger sensor area = shallower depth of field and better low-light performance.
Lens ecosystem
Native lens selection
EOS-1D X Mark III
✓ more lensesCanon EF
300+
native lenses available
645Z: mount data unavailable
Counts include current first-party and major third-party native autofocus lenses.
Use-case scoring
Which one for what?
Algorithmic scores from verified specs · 10 = best in class
Why pick one over the other
Reasons to choose
EOS-1D X Mark III
AF low-light limit
-4 EV vs -3 EV — lower is better
Dimensions (W×H×D mm)
Adds 138, 98, 88
ISO max (native)
102,400 vs 25,600 — higher is better
Weight
720 g vs 1470 g — lower is better
Burst (mechanical)
16 fps vs 8 fps — higher is better
Internal RAW video
Only EOS-1D X Mark III supports it
Card types
Adds CFexpress Type B
AF points / zones
191 vs 101 — higher is better
Reasons to choose
645Z
Dimensions (W×H×D mm)
Adds 156, 117, 123
Resolution
51.4 MP vs 20.1 MP — higher is better
Animal / bird AF
Only 645Z supports it
ISO min (native)
64 vs 100 — lower is better
Battery life (CIPA)
640 shots vs 520 shots — higher is better
Both cameras share
- ✓AA filter — Both support aa filter
- ✓AF frame coverage — Both 100 %
- ✓Eye AF — Both support eye af
- ✓Burst (electronic) — Both 20 fps
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
- ✓4K max frame rate — Both 60 fps
Pros & cons at a glance
Editorially curated highlights and trade-offs.
EOS-1D X Mark III
Pros
- ✓20fps DSLR
- ✓Pro build
- ✓Dual CFexpress
- ✓Excellent AF
Cons
- –DSLR platform
- –20MP
- –Very heavy
645Z
Pros
- ✓51MP medium format
- ✓CMOS sensor
- ✓Pentax color
- ✓Relatively affordable MF
Cons
- –Huge body
- –Slow operation
- –Limited lens line vs Hasselblad
Decided which one is right for you?
Compare live prices for the EOS-1D X Mark III and 645Z at major authorized retailers.
Canon EOS-1D X Mark III
Pentax 645Z
Affiliate disclosure: As an Amazon Associate, Cameraegg earns from qualifying purchases. Cameraegg may also earn commission from B&H links, at no extra cost to you.
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for landscape, EOS-1D X Mark III or 645Z?
645Z scores 8.0/10 versus 5.5/10 for EOS-1D X Mark III — 51.4MP — massive detail for large prints.
What's the resolution difference between the EOS-1D X Mark III and 645Z?
EOS-1D X Mark III is 20.1 MP and 645Z is 51.4 MP, so the 645Z captures more detail for cropping and large prints.
Do the EOS-1D X Mark III and 645Z have in-body image stabilization?
EOS-1D X Mark III has 8-stop in-body image stabilization, while 645Z has 7-stop in-body image stabilization.
Which shoots faster bursts — the EOS-1D X Mark III or the 645Z?
EOS-1D X Mark III reaches 20 fps electronic. 645Z reaches 20 fps electronic.
What's the weight difference between the EOS-1D X Mark III and 645Z?
EOS-1D X Mark III weighs 720 g and 645Z weighs 1470 g, so the EOS-1D X Mark III is 750 g lighter.
Do the EOS-1D X Mark III and 645Z record 4K video?
EOS-1D X Mark III: 4K up to 60p. 645Z: 4K up to 60p.
Are the EOS-1D X Mark III and 645Z weather sealed?
EOS-1D X Mark III: Yes. 645Z: Yes.
Which has better battery life?
Rated battery life is 520 shots (CIPA) for the EOS-1D X Mark III and 640 shots for the 645Z, giving the 645Z the edge.
How much does each cost?
EOS-1D X Mark III launched at $6,499 and 645Z at $8,499. The EOS-1D X Mark III is $2,000 less.
Can't decide between two? Compare a third camera.
Add any camera to get a three-way EOS-1D X Mark III vs 645Z vs X comparison.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.