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
Sony
Alpha 6600
APS-C with IBIS and huge NP-FZ100 battery in a compact body.
$1,399
Released Oct 2019
EOS R6 Mark III is 6.1 years newer.
Wins
EOS R6 Mark III
Wins
Alpha 6600
2 categories tied
TL;DR — Key differences
- AEOS R6 Mark III has higher Max video bit rate (2600 Mbps vs 150 Mbps)
- AEOS R6 Mark III has higher 4K max frame rate (120 fps vs 30 fps)
- AEOS R6 Mark III has higher Burst (electronic) (40 fps vs 11 fps)
- AEOS R6 Mark III has higher RAW buffer depth (150 frames vs 60 frames)
- AEOS R6 Mark III has higher AF points / zones (1053 vs 425)
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)
Alpha 6600
120 × 67 × 69 mm
503 g (1.11 lb / 17.74 oz)
EOS R6 Mark III is 18mm wider, 32mm taller, and 19mm thicker than Alpha 6600.
EOS R6 Mark III is 196 g heavier than Alpha 6600.
Depth (front-to-back): 88mm EOS R6 Mark III · 69mm Alpha 6600
Back view, to scale
Width × Height — same proportions as the front of the body.
EOS R6 Mark III
138 × 98 mm
Alpha 6600
120 × 67 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
Alpha 6600
120 × 69 mm
Sensor size, to scale
EOS R6 Mark III
35.9 × 23.9 mm · Full Frame
858 mm² area
Alpha 6600
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
Canon RF
105+
native lenses available
Alpha 6600
✓ more lensesSony E
350+
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
AF low-light limit
-6.5 EV vs -2 EV — lower is better
Subject recognition
Adds People, Dogs, Cats…
Dimensions (W×H×D mm)
Adds 138.4, 98.4, 88.4
Card types
Adds CFexpress Type B, SD UHS-II
Max video bit rate
2600 Mbps vs 150 Mbps — higher is better
Codecs
Adds CRM, XF-HEVC S, XF-AVC S…
4K max frame rate
120 fps vs 30 fps — higher is better
Burst (electronic)
40 fps vs 11 fps — higher is better
Reasons to choose
Alpha 6600
Subject recognition
Adds Human, Animal
Dimensions (W×H×D mm)
Adds 120, 66.9, 69.3
Card types
Adds SD UHS-I
Codecs
Adds XAVC S, AVCHD
Weight
503 g vs 699 g — lower is better
Battery life (CIPA)
810 shots vs 640 shots — higher is better
Both cameras share
- ✓ISO min (native) — Both 100
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓In-body stabilization — Both support in-body stabilization
- ✓Weather sealing — Both support weather sealing
- ✓EVF refresh rate — Both 120 Hz
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
Alpha 6600
Pros
- ✓IBIS in APS-C
- ✓Excellent battery
- ✓Real-time tracking AF
Cons
- –Older than A6700
- –Single slot
- –No 4K 60p
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for sports, EOS R6 Mark III or Alpha 6600?
EOS R6 Mark III scores 8.5/10 versus 4.0/10 for Alpha 6600 — 40fps burst — pro-level action capture.
What's the resolution difference between the EOS R6 Mark III and Alpha 6600?
EOS R6 Mark III is 32.5 MP and Alpha 6600 is 24.2 MP, so the EOS R6 Mark III captures more detail for cropping and large prints.
Do the EOS R6 Mark III and Alpha 6600 have in-body image stabilization?
EOS R6 Mark III has 8.5-stop in-body image stabilization, while alpha 6600 has 5-stop in-body image stabilization.
Which shoots faster bursts — the EOS R6 Mark III or the Alpha 6600?
EOS R6 Mark III reaches 40 fps electronic. Alpha 6600 reaches 11 fps electronic.
What's the weight difference between the EOS R6 Mark III and Alpha 6600?
EOS R6 Mark III weighs 699 g and Alpha 6600 weighs 503 g, so the Alpha 6600 is 196 g lighter.
Do the EOS R6 Mark III and Alpha 6600 record 4K video?
EOS R6 Mark III: 4K up to 120p. Alpha 6600: 4K up to 30p.
Are the EOS R6 Mark III and Alpha 6600 weather sealed?
EOS R6 Mark III: Yes. Alpha 6600: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the EOS R6 Mark III and 810 shots for the Alpha 6600, giving the Alpha 6600 the edge.
How much does each cost?
EOS R6 Mark III launched at $2,799 and Alpha 6600 at $1,399. The Alpha 6600 is $1,400 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of Canon and Sony press materials.