Pentax
645Z
51MP medium format DSLR that made digital MF accessible — still prized for landscape and studio.
$8,499
Launch priceReleased Apr 2014
Pentax
K-5 IIs
APS-C flagship without AA filter for maximum sharpness — a cult favorite among Pentax stills shooters.
$1,099
Launch priceReleased Sep 2012
645Z is 1.6 years newer.
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Wins
645Z
Wins
K-5 IIs
10 categories tied
Which would you choose?
TL;DR — Key differences
- A645Z has higher Resolution (51.4 MP vs 16.3 MP)
- BK-5 IIs has lower Weight (710 g vs 1470 g)
- A645Z has higher RAW buffer depth (120 frames vs 60 frames)
- A645Z has higher EVF resolution (3,690,000 vs 2,360,000)
- A645Z has lower ISO min (native) (64 vs 100)
Key specs at a glance
Size and weight, to scale
📸 Snap this size diff to share645Z
156 × 117 × 123 mm
1470 g (3.24 lb / 51.85 oz)
Credit card
85.6 × 54 mm
for scale
K-5 IIs
131 × 97 × 73 mm
710 g (1.57 lb / 25.04 oz)
645Z is 25mm wider, 20mm taller, and 50mm thicker than K-5 IIs.
645Z is 760 g heavier than K-5 IIs.
Depth (front-to-back): 123mm 645Z · 73mm K-5 IIs
Sensor size, to scale
645Z
43.8 × 32.8 mm · Medium Format
1437 mm² area
K-5 IIs
23.7 × 15.7 mm · APS-C
372 mm² area
3.9× larger sensor area = shallower depth of field and better low-light performance.
Lens ecosystem
Native lens selection
645Z: mount data unavailable
K-5 IIs
✓ more lensesPentax K
70+
native lenses available
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
645Z
Dimensions (W×H×D mm)
Adds 156, 117, 123
Resolution
51.4 MP vs 16.3 MP — higher is better
AA filter
Only 645Z supports it
RAW buffer depth
120 frames vs 60 frames — higher is better
EVF resolution
3,690,000 vs 2,360,000 — higher is better
ISO min (native)
64 vs 100 — lower is better
Burst (mechanical)
8 fps vs 6 fps — higher is better
Burst (electronic)
20 fps vs 15 fps — higher is better
Reasons to choose
K-5 IIs
Dimensions (W×H×D mm)
Adds 131, 97, 73
Weight
710 g vs 1470 g — lower is better
Both cameras share
- ✓ISO max (native) — Both 25,600
- ✓AF points / zones — Both 101
- ✓AF frame coverage — Both 100 %
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓Pre-Capture / Pre-Release — Both support pre-capture / pre-release
Pros & cons at a glance
Editorially curated highlights and trade-offs.
645Z
Pros
- ✓51MP medium format
- ✓CMOS sensor
- ✓Pentax color
- ✓Relatively affordable MF
Cons
- –Huge body
- –Slow operation
- –Limited lens line vs Hasselblad
K-5 IIs
Pros
- ✓No AA filter
- ✓Weather sealed
- ✓Excellent build
- ✓Strong JPEG engine
Cons
- –16MP dated
- –Slow AF
- –DSLR declining
Decided which one is right for you?
Compare live prices for the 645Z and K-5 IIs at major authorized retailers.
Pentax 645Z
Pentax K-5 IIs
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Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for landscape, 645Z or K-5 IIs?
645Z scores 8.0/10 versus 3.5/10 for K-5 IIs — 51.4MP — massive detail for large prints.
What's the resolution difference between the 645Z and K-5 IIs?
645Z is 51.4 MP and K-5 IIs is 16.3 MP, so the 645Z captures more detail for cropping and large prints.
Do the 645Z and K-5 IIs have in-body image stabilization?
645Z has 7-stop in-body image stabilization, while K-5 IIs has 6-stop in-body image stabilization.
Which shoots faster bursts — the 645Z or the K-5 IIs?
645Z reaches 20 fps electronic. K-5 IIs reaches 15 fps electronic.
What's the weight difference between the 645Z and K-5 IIs?
645Z weighs 1470 g and K-5 IIs weighs 710 g, so the K-5 IIs is 760 g lighter.
Do the 645Z and K-5 IIs record 4K video?
645Z: 4K up to 60p. K-5 IIs: 4K up to 60p.
Are the 645Z and K-5 IIs weather sealed?
645Z: Yes. K-5 IIs: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the 645Z and 640 shots for the K-5 IIs, giving the K-5 IIs the edge.
How much does each cost?
645Z launched at $8,499 and K-5 IIs at $1,099. The K-5 IIs is $7,400 less.
Can't decide between two? Compare a third camera.
Add any camera to get a three-way 645Z vs K-5 IIs vs X comparison.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.