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Sony

Alpha 7S III

12MP low-light video specialist with 4K 120p, 16-bit RAW HDMI, and excellent autofocus.

$3,499

Released Sep 2020

vs

Sony

Alpha 9

First stacked-sensor mirrorless sports camera with 20fps blackout-free shooting.

$4,499

Released Apr 2017

Alpha 7S III is 3.3 years newer.

Wins

10categories

Alpha 7S III

Video & HybridPortrait

Wins

5categories

Alpha 9

PortraitTravel

3 categories tied

TL;DR — Key differences

Alpha 7S III wins 4 categories·Alpha 9 wins 1 categories
  • AAlpha 7S III has higher 4K max frame rate (120 fps vs 30 fps)
  • AAlpha 7S III has higher Max video bit rate (600 Mbps vs 150 Mbps)
  • AAlpha 7S III has higher EVF resolution (9,437,184 vs 3,686,400)
  • BAlpha 9 has higher Resolution (24.2 MP vs 12.1 MP)
  • AAlpha 7S III has higher ISO max (native) (102,400 vs 51,200)

Key specs at a glance

Alpha 7S IIIAlpha 9
Resolution12.1 MP24.2 MP
SensorFull FrameFull Frame
ISO max102,40051,200
Burst10 fps20 fps
4K120 fps30 fps
IBIS5.5-stop5-stop
Weight699 g673 g
Battery600 shots650 shots

Size and weight, to scale

Alpha 7S III

129 × 97 × 81 mm

699 g (1.54 lb / 24.66 oz)

Alpha 9

127 × 96 × 63 mm

673 g (1.48 lb / 23.74 oz)

Alpha 7S III is 2mm wider, 1mm taller, and 18mm thicker than Alpha 9.

Alpha 7S III is 26 g heavier than Alpha 9.

Depth (front-to-back): 81mm Alpha 7S III · 63mm Alpha 9

Sensor size, to scale

Alpha 7S III

35.6 × 23.8 mm · Full Frame

847 mm² area

Alpha 9

35.6 × 23.8 mm · Full Frame

847 mm² area

Lens ecosystem

Native lens selection

Alpha 7S III

✓ more lenses

Sony E

350+

native lenses available

80 first-party270 third-party

Alpha 9

✓ more lenses

Sony E

350+

native lenses available

80 first-party270 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 caseAlpha 7S IIIAlpha 9
Portrait
6.5Good
7.5Good✓ wins
Sports & Action
4.0Fair
6.0Good✓ wins
Video & Hybrid
8.0Excellent✓ wins
5.0Fair
Landscape
5.5Fair
7.0Good✓ wins
Travel
6.5Good
7.5Good✓ wins
Wildlife
5.5Fair
6.5Good✓ wins
Vlogging
5.5Fair✓ wins
4.5Fair

Why pick one over the other

Reasons to choose

Alpha 7S III

  • AF low-light limit

    -6 EV vs -3 EV — lower is better

  • Dimensions (W×H×D mm)

    Adds 128.9, 96.9, 80.8

  • 4K max frame rate

    120 fps vs 30 fps — higher is better

  • Max video bit rate

    600 Mbps vs 150 Mbps — higher is better

  • EVF resolution

    9,437,184 vs 3,686,400 — higher is better

  • Codecs

    Adds XAVC HS, XAVC S-I, H.265

  • ISO max (native)

    102,400 vs 51,200 — higher is better

  • Burst (mechanical)

    10 fps vs 5 fps — higher is better

Reasons to choose

Alpha 9

  • Dimensions (W×H×D mm)

    Adds 126.9, 95.6, 63

  • Resolution

    24.2 MP vs 12.1 MP — higher is better

  • Burst (electronic)

    20 fps vs 10 fps — higher is better

  • Card types

    Adds SD UHS-I

  • RAW buffer depth

    200 frames vs 120 frames — higher is better

  • Codecs

    Adds AVCHD

  • Battery life (CIPA)

    650 shots vs 600 shots — higher is better

  • Weight

    673 g vs 699 g — lower is better

Both cameras share

  • AA filterBoth support aa filter
  • AF frame coverageBoth 94 %
  • Eye AFBoth support eye af
  • Animal / bird AFBoth support animal / bird af
  • In-body stabilizationBoth support in-body stabilization
  • Weather sealingBoth support weather sealing

Pros & cons at a glance

Editorially curated highlights and trade-offs.

Alpha 7S III

Pros

  • Best-in-class low light
  • 4K 120p
  • Full-size HDMI
  • Strong IBIS

Cons

  • 12MP stills limit
  • Older generation now
  • No 8K

Alpha 9

Pros

  • Stacked sensor pioneer
  • 20fps silent burst
  • Pro sports AF

Cons

  • Superseded by A9 II/III
  • 24MP
  • Expensive when new

Full specifications

= category winner

Alpha 7S III
Alpha 9
Resolution
12.1 MP
24.2 MP2× more
Sensor type
Full Frame Exmor R CMOS
Full Frame Stacked Exmor RS CMOS
Sensor size
35.6 × 23.8 mm
35.6 × 23.8 mm
AA filter
Yes
Yes
Alpha 7S III
Alpha 9
AF system
Fast Hybrid AF (phase-detection / contrast-detection)
Fast Hybrid AF (phase-detection / contrast-detection)
AF points / zones
759+10%
693
AF frame coverage
94 %
94 %
AF low-light limit
-6 EV
-3 EV
Eye AF
Yes
Yes
Animal / bird AF
Yes
Yes
Subject recognition
Human, Animal
Human, Animal
Alpha 7S III
Alpha 9
Burst (mechanical)
10 fps2× more
5 fps
Burst (electronic)
10 fps
20 fps2× more
Pre-Capture / Pre-Release
No
No
RAW buffer depth
120 frames
200 frames+67%
Alpha 7S III
Alpha 9
Max resolution
4K UHD
4K UHD
4K max frame rate
120 fps4× more
30 fps
Max video bit rate
600 Mbps4× more
150 Mbps
Internal RAW video
Yes
No
Log profile
S-Log3 / HLG / S-Cinetone
Picture Profile
Codecs
XAVC HS, XAVC S, XAVC S-I, H.265, H.264
XAVC S, AVCHD, H.264
Alpha 7S III
Alpha 9
Weight
699 g
673 g−26 g less
Dimensions (W×H×D mm)
128.9 × 96.9 × 80.8 mm
126.9 × 95.6 × 63 mm
Weather sealing
Yes
Yes

Frequently asked

Quick answers generated from verified specs.

Which is better for video, Alpha 7S III or Alpha 9?

Alpha 7S III scores 8.0/10 versus 5.0/10 for Alpha 9 — 4K recording.

What's the resolution difference between the Alpha 7S III and Alpha 9?

Alpha 7S III is 12.1 MP and Alpha 9 is 24.2 MP, so the Alpha 9 captures more detail for cropping and large prints.

Do the Alpha 7S III and Alpha 9 have in-body image stabilization?

Alpha 7S III has 5.5-stop in-body image stabilization, while alpha 9 has 5-stop in-body image stabilization.

Which shoots faster bursts — the Alpha 7S III or the Alpha 9?

Alpha 7S III reaches 10 fps electronic. Alpha 9 reaches 20 fps electronic.

What's the weight difference between the Alpha 7S III and Alpha 9?

Alpha 7S III weighs 699 g and Alpha 9 weighs 673 g, so the Alpha 9 is 26 g lighter.

Do the Alpha 7S III and Alpha 9 record 4K video?

Alpha 7S III: 4K up to 120p. Alpha 9: 4K up to 30p.

Are the Alpha 7S III and Alpha 9 weather sealed?

Alpha 7S III: Yes. Alpha 9: Yes.

Which has better battery life?

Rated battery life is 600 shots (CIPA) for the Alpha 7S III and 650 shots for the Alpha 9, giving the Alpha 9 the edge.

How much does each cost?

Alpha 7S III launched at $3,499 and Alpha 9 at $4,499. The Alpha 7S III is $1,000 less.

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