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
Released Nov 2025
OM System
OM-3 ASTRO
Astrophotography-focused OM-3 variant with 20.4MP stacked sensor, H-alpha-friendly filter tuning, IP53 sealing, and 7.5-stop Sync IS.
$2,499
Released Jul 2025
EOS R6 Mark III is 4 months newer.
Wins
EOS R6 Mark III
Wins
OM-3 ASTRO
4 categories tied
TL;DR — Key differences
- AEOS R6 Mark III has higher Max video bit rate (2600 Mbps vs 150 Mbps)
- BOM-3 ASTRO has higher Burst (electronic) (120 fps vs 40 fps)
- AEOS R6 Mark III has higher 4K max frame rate (120 fps vs 60 fps)
- AEOS R6 Mark III has higher Card slots (2 vs 1)
- BOM-3 ASTRO has higher ISO max (native) (102,400 vs 64,000)
Key specs at a glance
Size and weight, to scale
EOS R6 Mark III
138 × 98 × 88 mm
699 g (1.54 lb / 24.66 oz)
OM-3 ASTRO
139 × 89 × 46 mm
496 g (1.09 lb / 17.50 oz)
EOS R6 Mark III is 1mm narrower than OM-3 ASTRO but it is also 10mm taller and 43mm thicker.
EOS R6 Mark III is 203 g heavier than OM-3 ASTRO.
Depth (front-to-back): 88mm EOS R6 Mark III · 46mm OM-3 ASTRO
Back view, to scale
Width × Height — same proportions as the front of the body.
EOS R6 Mark III
138 × 98 mm
OM-3 ASTRO
139 × 89 mm
Top view, to scale
Width × Depth (front-to-back) — see which body is chunkier on the table.
EOS R6 Mark III
138 × 88 mm
OM-3 ASTRO
139 × 46 mm
Sensor size, to scale
EOS R6 Mark III
35.9 × 23.9 mm · Full Frame
858 mm² area
OM-3 ASTRO
17.4 × 13 mm · Compact / large-type
226 mm² area
3.8× larger sensor area = shallower depth of field and better low-light performance.
Lens ecosystem
Native lens selection
EOS R6 Mark III
Canon RF
105+
native lenses available
OM-3 ASTRO
✓ more lensesMicro Four Thirds
130+
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
EOS R6 Mark III
Dimensions (W×H×D mm)
Adds 138.4, 98.4, 88.4
Max video bit rate
2600 Mbps vs 150 Mbps — higher is better
Subject recognition
Adds Dogs, Cats, Horses…
Codecs
Adds CRM, XF-HEVC S, XF-AVC S
AA filter
Only EOS R6 Mark III supports it
4K max frame rate
120 fps vs 60 fps — higher is better
Internal RAW video
Only EOS R6 Mark III supports it
Card slots
2 vs 1 — higher is better
Reasons to choose
OM-3 ASTRO
AF low-light limit
-8 EV vs -6.5 EV — lower is better
Dimensions (W×H×D mm)
Adds 139.3, 88.9, 45.8
Burst (electronic)
120 fps vs 40 fps — higher is better
Subject recognition
Adds Animals, Motorsports, Airplanes
Card types
Adds SD UHS-I
ISO max (native)
102,400 vs 64,000 — higher is better
Codecs
Adds MOV
Weight
496 g vs 699 g — lower is better
Both cameras share
- ✓AF points / zones — Both 1053
- ✓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
- ✓In-body stabilization — Both support in-body stabilization
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
OM-3 ASTRO
Pros
- ✓Astro-tuned sensor filter
- ✓20.4MP stacked BSI Live MOS
- ✓IP53 weather sealing
- ✓7.5-stop Sync IS
Cons
- –Specialized astro variant
- –Micro Four Thirds sensor
- –Premium price
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for landscape, EOS R6 Mark III or OM-3 ASTRO?
EOS R6 Mark III scores 7.5/10 versus 2.5/10 for OM-3 ASTRO — 32.5MP — ample resolution.
What's the resolution difference between the EOS R6 Mark III and OM-3 ASTRO?
EOS R6 Mark III is 32.5 MP and OM-3 ASTRO is 20.4 MP, so the EOS R6 Mark III captures more detail for cropping and large prints.
Do the EOS R6 Mark III and OM-3 ASTRO have in-body image stabilization?
EOS R6 Mark III has 8.5-stop in-body image stabilization, while oM-3 ASTRO has 6.5-stop in-body image stabilization.
Which shoots faster bursts — the EOS R6 Mark III or the OM-3 ASTRO?
EOS R6 Mark III reaches 40 fps electronic. OM-3 ASTRO reaches 120 fps electronic.
What's the weight difference between the EOS R6 Mark III and OM-3 ASTRO?
EOS R6 Mark III weighs 699 g and OM-3 ASTRO weighs 496 g, so the OM-3 ASTRO is 203 g lighter.
Do the EOS R6 Mark III and OM-3 ASTRO record 4K video?
EOS R6 Mark III: 4K up to 120p. OM-3 ASTRO: 4K up to 60p.
Are the EOS R6 Mark III and OM-3 ASTRO weather sealed?
EOS R6 Mark III: Yes. OM-3 ASTRO: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the EOS R6 Mark III and 640 shots for the OM-3 ASTRO, giving the OM-3 ASTRO the edge.
How much does each cost?
EOS R6 Mark III launched at $2,799 and OM-3 ASTRO at $2,499. The OM-3 ASTRO is $300 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of Canon and OM System press materials.