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EOS R6 Mark III

Canon

EOS R6 Mark III

Hybrid 32.5MP full-frame RF body with 7K RAW video, 40fps electronic burst, 8.5-stop IBIS, and Dual Pixel CMOS AF II.

$2,799

Launch price

Released Nov 2025

vs

Pentax

K-3 Mark III Monochrome

Monochrome-only APS-C DSLR with 25.7MP sensor, IBIS, optical viewfinder, and weather sealing.

$2,199

Launch price

Released Apr 2024

EOS R6 Mark III is 1.5 years newer.

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Wins

11categories

EOS R6 Mark III

Sports & ActionPortrait

Wins

1categories

K-3 Mark III Monochrome

WildlifePortrait

6 categories tied

Which would you choose?

TL;DR — Key differences

EOS R6 Mark III wins 5 categories·K-3 Mark III Monochrome wins 0 categories
  • AEOS R6 Mark III has higher Max video bit rate (2600 Mbps vs 150 Mbps)
  • AEOS R6 Mark III has higher AF points / zones (1053 vs 101)
  • AEOS R6 Mark III has higher ISO max (native) (64,000 vs 25,600)
  • AEOS R6 Mark III has higher Burst (electronic) (40 fps vs 20 fps)
  • AEOS R6 Mark III has higher 4K max frame rate (120 fps vs 60 fps)

Key specs at a glance

EOS R6 Mark IIIK-3 Mark III Monochrome
Resolution32.5 MP25.7 MP
SensorFull FrameAPS-C
ISO max64,00025,600
Burst40 fps20 fps
4K120 fps60 fps
IBIS8.5-stop5.5-stop
Weight699 g820 g
Battery640 shots640 shots

Size and weight, to scale

EOS R6 Mark III front view

EOS R6 Mark III

138 × 98 × 88 mm

699 g (1.54 lb / 24.66 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 Monochrome

135 × 104 × 74 mm

820 g (1.81 lb / 28.92 oz)

EOS R6 Mark III is 5mm shorter than K-3 Mark III Monochrome but it is also 4mm wider and 15mm thicker.

EOS R6 Mark III is 121 g lighter than K-3 Mark III Monochrome.

Depth (front-to-back): 88mm EOS R6 Mark III · 74mm K-3 Mark III Monochrome

Back view, to scale

Width × Height — same proportions as the front of the body.

EOS R6 Mark III back view

EOS R6 Mark III

138 × 98 mm

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

Credit card

85.6 × 54 mm

K-3 Mark III Monochrome

135 × 104 mm

Top view, to scale

Width × Depth (front-to-back) — see which body is chunkier on the table.

EOS R6 Mark III top view

EOS R6 Mark III

138 × 88 mm

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

Credit card

85.6 × 54 mm

K-3 Mark III Monochrome

135 × 74 mm

Sensor size, to scale

EOS R6 Mark III

35.9 × 23.9 mm · Full Frame

858 mm² area

K-3 Mark III Monochrome

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

EOS R6 Mark III

✓ more lenses

Canon RF

105+

native lenses available

45 first-party60 third-party

K-3 Mark III Monochrome

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 caseEOS R6 Mark IIIK-3 Mark III Monochrome
Portrait
8.0Excellent✓ wins
6.5Good
Sports & Action
10.0Excellent✓ wins
6.5Good
Video & Hybrid
6.5Good✓ wins
6.0Good
Landscape
7.5Good✓ wins
5.0Fair
Travel
7.5Good✓ wins
6.5Good
Wildlife
6.5Good
10.0Excellent✓ wins
Vlogging
5.5Fair
5.5Fair

Why pick one over the other

Reasons to choose

EOS R6 Mark III

  • AF low-light limit

    -6.5 EV vs -3 EV — lower is better

  • Subject recognition

    Adds People, Dogs, Cats…

  • Dimensions (W×H×D mm)

    Adds 138.4, 98.4, 88.4

  • Max video bit rate

    2600 Mbps vs 150 Mbps — higher is better

  • AF points / zones

    1053 vs 101 — higher is better

  • ISO max (native)

    64,000 vs 25,600 — higher is better

  • Codecs

    Adds CRM, XF-HEVC S, XF-AVC S

  • AA filter

    Only EOS R6 Mark III supports it

Reasons to choose

K-3 Mark III Monochrome

  • Subject recognition

    Adds Human, Animal, Bird…

  • Dimensions (W×H×D mm)

    Adds 134.5, 103.5, 73.5

  • EVF magnification

    0.78 × vs 0.76 × — higher is better

Both cameras share

  • ISO min (native)Both 100
  • AF frame coverageBoth 100 %
  • Eye AFBoth support eye af
  • Animal / bird AFBoth support animal / bird af
  • Pre-Capture / Pre-ReleaseBoth 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.

EOS R6 Mark III

Pros

  • 32.5MP full-frame sensor
  • 7K RAW video & 4K 120p
  • 40fps electronic burst with Pre-Continuous
  • 8.5-stop IBIS

Cons

  • Single CFexpress Type B + SD slot
  • Smaller LCD than R5 II
  • LP-E6P required for full features

K-3 Mark III Monochrome

Pros

  • Dedicated monochrome sensor
  • Optical viewfinder
  • IBIS in a DSLR
  • Weather sealed

Cons

  • Black-and-white only
  • DSLR platform
  • Limited video

Decided which one is right for you?

Compare live prices for the EOS R6 Mark III and K-3 Mark III Monochrome 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

EOS R6 Mark III
K-3 Mark III Monochrome
Resolution
32.5 MP+26%
25.7 MP
Sensor type
Full Frame CMOS
Monochrome APS-C CMOS
Sensor size
35.9 × 23.9 mm
23.5 × 15.6 mm
AA filter
Yes
No
EOS R6 Mark III
K-3 Mark III Monochrome
Processor
DIGIC X
Image processor
EOS R6 Mark III
K-3 Mark III Monochrome
ISO min (native)
100
100
ISO max (native)
64,000+1.3 stops
25,600
ISO max (expanded)
102,400
102,400
EOS R6 Mark III
K-3 Mark III Monochrome
Shutter type
Mechanical / Electronic 1st Curtain + 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 sports, EOS R6 Mark III or K-3 Mark III Monochrome?

EOS R6 Mark III scores 10.0/10 versus 6.5/10 for K-3 Mark III Monochrome — 40fps burst — pro-level action capture.

What's the resolution difference between the EOS R6 Mark III and K-3 Mark III Monochrome?

EOS R6 Mark III is 32.5 MP and K-3 Mark III Monochrome is 25.7 MP, so the EOS R6 Mark III captures more detail for cropping and large prints.

Do the EOS R6 Mark III and K-3 Mark III Monochrome have in-body image stabilization?

EOS R6 Mark III has 8.5-stop in-body image stabilization, while K-3 Mark III Monochrome has 5.5-stop in-body image stabilization.

Which shoots faster bursts — the EOS R6 Mark III or the K-3 Mark III Monochrome?

EOS R6 Mark III reaches 40 fps electronic. K-3 Mark III Monochrome reaches 20 fps electronic.

What's the weight difference between the EOS R6 Mark III and K-3 Mark III Monochrome?

EOS R6 Mark III weighs 699 g and K-3 Mark III Monochrome weighs 820 g, so the EOS R6 Mark III is 121 g lighter.

Do the EOS R6 Mark III and K-3 Mark III Monochrome record 4K video?

EOS R6 Mark III: 4K up to 120p. K-3 Mark III Monochrome: 4K up to 60p.

Are the EOS R6 Mark III and K-3 Mark III Monochrome weather sealed?

EOS R6 Mark III: Yes. K-3 Mark III Monochrome: Yes.

Which has better battery life?

Rated battery life is 640 shots (CIPA) for the EOS R6 Mark III and 640 shots for the K-3 Mark III Monochrome, giving the K-3 Mark III Monochrome the edge.

How much does each cost?

EOS R6 Mark III launched at $2,799 and K-3 Mark III Monochrome at $2,199. The K-3 Mark III Monochrome is $600 less.

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

Add any camera to get a three-way EOS R6 Mark III vs K-3 Mark III Monochrome vs X comparison.

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

Product images courtesy of Canon and Pentax press materials.