Cameraegg Compare logoCameraegg

Pentax

K-1

Original 36MP full-frame Pentax DSLR with 5-axis SR, AA filter simulator, and weather sealing.

$1,799

Launch price

Released Apr 2016

Check Price on AmazonCheck Price on B&H
Full specs →
vs

Pentax

K-3 Mark III

APS-C DSLR flagship with optical viewfinder and weather sealing.

$1,999

Launch price

Released Apr 2021

Check Price on AmazonCheck Price on B&H
Full specs →

K-3 Mark III is 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

1categories

K-1

★ Wildlife★ Portrait

Wins

2categories

K-3 Mark III

★ Wildlife★ Travel

15 categories tied

Which would you choose?

TL;DR — Key differences

K-1 wins 1 categories·K-3 Mark III wins 2 categories
  • BK-3 Mark III has lower Weight (520 g vs 1010 g)
  • AK-1 has higher Resolution (36.4 MP vs 25.7 MP)
  • BK-3 Mark III has higher IBIS effectiveness (7 stops vs 5 stops)

Key specs at a glance

K-1K-3 Mark III
Resolution36.4 MP25.7 MP
SensorFull FrameAPS-C
ISO max25,60025,600
Burst20 fps20 fps
4K60 fps60 fps
IBIS5-stop7-stop
Weight1010 g520 g
Battery640 shots640 shots

Size and weight, to scale

K-1

137 × 111 × 87 mm

1010 g (2.23 lb / 35.63 oz)

Credit card shown to scale as a size reference (ISO 7810, 85.6 × 54 mm)

Credit card

85.6 × 54 mm

for scale

K-3 Mark III

138 × 98 × 88 mm

520 g (1.15 lb / 18.34 oz)

K-1 is 1mm narrower and 2mm thinner than K-3 Mark III but it is also 13mm taller.

K-1 is 490 g heavier than K-3 Mark III.

Depth (front-to-back): 87mm K-1 · 88mm K-3 Mark III

Sensor size, to scale

K-1

35.9 × 24 mm · Full Frame

862 mm² area

K-3 Mark III

23.5 × 15.6 mm · APS-C

367 mm² area

2.3× larger sensor area = shallower depth of field and better low-light performance.

Lens ecosystem

Native lens selection

K-1

✓ more lenses

Pentax K

70+

native lenses available

30 first-party40 third-party

K-3 Mark III

✓ more lenses

Pentax K

70+

native lenses available

30 first-party40 third-party

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

Use caseK-1K-3 Mark III
Portrait
8.0Excellent✓ wins
6.5Good
Sports & Action
6.5Good
6.5Good
Video & Hybrid
6.0Good
6.0Good
Landscape
7.5Good✓ wins
5.0Fair
Travel
6.5Good
8.5Excellent✓ wins
Wildlife
9.0Excellent
10.0Excellent✓ wins
Vlogging
5.5Fair
7.0Good✓ wins

Why pick one over the other

Reasons to choose

K-1

  • Dimensions (W×H×D mm)

    Adds 137, 110.5, 86.5

  • AA filter

    Only K-1 supports it

  • Resolution

    36.4 MP vs 25.7 MP — higher is better

Reasons to choose

K-3 Mark III

  • Dimensions (W×H×D mm)

    Adds 138, 98, 88

  • Weight

    520 g vs 1010 g — lower is better

  • IBIS effectiveness

    7 stops vs 5 stops — higher is better

Both cameras share

  • ✓ISO min (native) — Both 100
  • ✓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

Pros & cons at a glance

Editorially curated highlights and trade-offs.

K-1

Pros

  • ✓36MP full-frame
  • ✓IBIS in DSLR
  • ✓AA filter simulator
  • ✓Weather sealed

Cons

  • –Slow AF vs mirrorless
  • –Heavy
  • –Superseded by K-1 II

K-3 Mark III

Pros

  • ✓Optical viewfinder
  • ✓Weather sealed
  • ✓IBIS in DSLR

Cons

  • –DSLR system declining
  • –APS-C
  • –Limited video

Decided which one is right for you?

Compare live prices for the K-1 and K-3 Mark III at major authorized retailers.

Pentax K-1

Check Price on AmazonCheck Price on B&H

Pentax K-3 Mark III

Check Price on AmazonCheck Price on B&H

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

K-1
K-3 Mark III
Resolution
36.4 MP✓+42%
25.7 MP
Sensor type
Full Frame CMOS
APS-C CMOS
Sensor size
35.9 × 24.0 mm
23.5 × 15.6 mm
AA filter
Yes
No
K-1
K-3 Mark III
Processor
Image processor
Image processor
K-1
K-3 Mark III
ISO min (native)
100
100
ISO max (native)
25,600
25,600
ISO max (expanded)
102,400
102,400
K-1
K-3 Mark III
Shutter type
Mechanical + Electronic
Mechanical + Electronic
Max mechanical speed
1/8000 sec
1/8000 sec
Max electronic speed
1/16000 sec
1/16000 sec

Frequently asked

Quick answers generated from verified specs.

Which is better for landscape, K-1 or K-3 Mark III?

K-1 scores 7.5/10 versus 5.0/10 for K-3 Mark III — 36.4MP — ample resolution.

What's the resolution difference between the K-1 and K-3 Mark III?

K-1 is 36.4 MP and K-3 Mark III is 25.7 MP, so the K-1 captures more detail for cropping and large prints.

Do the K-1 and K-3 Mark III have in-body image stabilization?

K-1 has 5-stop in-body image stabilization, while K-3 Mark III has 7-stop in-body image stabilization.

Which shoots faster bursts — the K-1 or the K-3 Mark III?

K-1 reaches 20 fps electronic. K-3 Mark III reaches 20 fps electronic.

What's the weight difference between the K-1 and K-3 Mark III?

K-1 weighs 1010 g and K-3 Mark III weighs 520 g, so the K-3 Mark III is 490 g lighter.

Do the K-1 and K-3 Mark III record 4K video?

K-1: 4K up to 60p. K-3 Mark III: 4K up to 60p.

Are the K-1 and K-3 Mark III weather sealed?

K-1: Yes. K-3 Mark III: Yes.

Which has better battery life?

Rated battery life is 640 shots (CIPA) for the K-1 and 640 shots for the K-3 Mark III, giving the K-3 Mark III the edge.

How much does each cost?

K-1 launched at $1,799 and K-3 Mark III at $1,999. The K-1 is $200 less.

Can't decide between two? Compare a third camera.

Add any camera to get a three-way K-1 vs K-3 Mark III vs X comparison.

Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.