Nikon
Z9
Flagship stacked mirrorless with 45MP, 8K video, and no mechanical shutter.
$5,499
Launch priceReleased Oct 2021
Pentax
645Z
51MP medium format DSLR that made digital MF accessible — still prized for landscape and studio.
$8,499
Launch priceReleased Apr 2014
Z9 is 7.5 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
Z9
Wins
645Z
4 categories tied
Which would you choose?
TL;DR — Key differences
- B645Z has higher Burst (mechanical) (8 fps vs 0 fps)
- AZ9 has higher RAW buffer depth (1000 frames vs 120 frames)
- AZ9 has higher Burst (electronic) (120 fps vs 20 fps)
- AZ9 has higher AF points / zones (493 vs 101)
- AZ9 has higher 4K max frame rate (120 fps vs 60 fps)
Key specs at a glance
Size and weight, to scale
📸 Snap this size diff to share
Z9
149 × 150 × 91 mm
1160 g (2.56 lb / 40.92 oz)
Credit card
85.6 × 54 mm
for scale
645Z
156 × 117 × 123 mm
1470 g (3.24 lb / 51.85 oz)
Z9 is 7mm narrower and 33mm thinner than 645Z but it is also 33mm taller.
Z9 is 310 g lighter than 645Z.
Depth (front-to-back): 91mm Z9 · 123mm 645Z
Back view, to scale
Width × Height — same proportions as the front of the body.
Z9
149 × 150 mm
Credit card
85.6 × 54 mm
645Z
156 × 117 mm
Top view, to scale
Width × Depth (front-to-back) — see which body is chunkier on the table.
Z9
149 × 91 mm
Credit card
85.6 × 54 mm
645Z
156 × 123 mm
Sensor size, to scale
Z9
35.9 × 23.9 mm · Full Frame
858 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
Z9
✓ more lensesNikon Z
90+
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
Z9
AF low-light limit
-8.5 EV vs -3 EV — lower is better
Subject recognition
Adds People, Birds, Dogs…
Codecs
Adds N-RAW, ProRes RAW HQ, ProRes 422 HQ…
Dimensions (W×H×D mm)
Adds 149, 149.5, 90.5
Card types
Adds CFexpress Type B / XQD, CFexpress Type B / XQD
RAW buffer depth
1000 frames vs 120 frames — higher is better
Burst (electronic)
120 fps vs 20 fps — higher is better
AF points / zones
493 vs 101 — higher is better
Reasons to choose
645Z
Subject recognition
Adds Human, Animal, Bird…
Burst (mechanical)
8 fps vs 0 fps — higher is better
Codecs
Adds H.265, H.264
Dimensions (W×H×D mm)
Adds 156, 117, 123
Card types
Adds SD UHS-II
AA filter
Only 645Z supports it
IBIS effectiveness
7 stops vs 6 stops — higher is better
Resolution
51.4 MP vs 45.7 MP — higher is better
Both cameras share
- ✓ISO min (native) — Both 64
- ✓ISO max (native) — Both 25,600
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
- ✓In-body stabilization (IBIS) — Both support in-body stabilization (ibis)
Pros & cons at a glance
Editorially curated highlights and trade-offs.
Z9
Pros
- ✓45MP stacked
- ✓8K 60p internal
- ✓120fps stills
- ✓Pro build
Cons
- –Heavy body
- –Expensive
- –Large files
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 Z9 and 645Z at major authorized retailers.
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 sports, Z9 or 645Z?
Z9 scores 10.0/10 versus 6.5/10 for 645Z — 120fps burst — pro-level action capture.
What's the resolution difference between the Z9 and 645Z?
Z9 is 45.7 MP and 645Z is 51.4 MP, so the 645Z captures more detail for cropping and large prints.
Do the Z9 and 645Z have in-body image stabilization?
Z9 has 6-stop in-body image stabilization, while 645Z has 7-stop in-body image stabilization.
Which shoots faster bursts — the Z9 or the 645Z?
Z9 reaches 120 fps electronic. 645Z reaches 20 fps electronic.
What's the weight difference between the Z9 and 645Z?
Z9 weighs 1160 g and 645Z weighs 1470 g, so the Z9 is 310 g lighter.
Do the Z9 and 645Z record 4K video?
Z9: 8K UHD (max), 4K up to 120p. 645Z: 4K up to 60p.
Are the Z9 and 645Z weather sealed?
Z9: Yes. 645Z: Yes.
Which has better battery life?
Rated battery life is 740 shots (CIPA) for the Z9 and 640 shots for the 645Z, giving the Z9 the edge.
How much does each cost?
Z9 launched at $5,499 and 645Z at $8,499. The Z9 is $3,000 less.
Can't decide between two? Compare a third camera.
Add any camera to get a three-way Z9 vs 645Z vs X comparison.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.
Product images courtesy of Nikon and Pentax press materials.