Sony
Alpha 7S III
12MP low-light video specialist with 4K 120p, 16-bit RAW HDMI, and excellent autofocus.
$3,499
Released Sep 2020
Sony
FX6
Full-frame cinema camcorder with dual base ISO and pro broadcast features.
$5,999
Released Nov 2020
FX6 is 3 months newer.
Wins
Alpha 7S III
Wins
FX6
6 categories tied
TL;DR — Key differences
- AAlpha 7S III has higher Burst (mechanical) (10 fps vs 0 fps)
- AAlpha 7S III has higher Burst (electronic) (10 fps vs 0 fps)
- AAlpha 7S III has higher IBIS effectiveness (5.5 stops vs 0 stops)
- AAlpha 7S III has lower ISO min (native) (80 vs 800)
- AAlpha 7S III has higher ISO max (native) (102,400 vs 12,800)
Key specs at a glance
Size and weight, to scale
Alpha 7S III
129 × 97 × 81 mm
699 g (1.54 lb / 24.66 oz)
FX6
114 × 116 × 153 mm
890 g (1.96 lb / 31.39 oz)
Alpha 7S III is 19mm shorter and 72mm thinner than FX6 but it is also 15mm wider.
Alpha 7S III is 191 g lighter than FX6.
Depth (front-to-back): 81mm Alpha 7S III · 153mm FX6
Sensor size, to scale
Alpha 7S III
35.6 × 23.8 mm · Full Frame
847 mm² area
FX6
35.6 × 23.8 mm · Full Frame
847 mm² area
Lens ecosystem
Native lens selection
Alpha 7S III
✓ more lensesSony E
350+
native lenses available
FX6
✓ 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
Alpha 7S III
Burst (mechanical)
10 fps vs 0 fps — higher is better
Burst (electronic)
10 fps vs 0 fps — higher is better
IBIS effectiveness
5.5 stops vs 0 stops — higher is better
Dimensions (W×H×D mm)
Adds 128.9, 96.9, 80.8
ISO min (native)
80 vs 800 — lower is better
ISO max (native)
102,400 vs 12,800 — higher is better
Codecs
Adds XAVC HS, XAVC S, XAVC S-I…
Internal RAW video
Only Alpha 7S III supports it
Reasons to choose
FX6
Dimensions (W×H×D mm)
Adds 114, 116, 153
Codecs
Adds XAVC-I, XAVC-L
Both cameras share
- ✓AA filter — Both support aa filter
- ✓AF frame coverage — Both 94 %
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓4K max frame rate — Both 120 fps
- ✓Max video bit rate — Both 600 Mbps
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
FX6
Pros
- ✓Dual base ISO
- ✓Pro cinema workflow
- ✓Internal XAVC
- ✓ND filters
Cons
- –Fixed lens mount needs adapters
- –Large for solo travel
- –Premium price
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for video, Alpha 7S III or FX6?
Alpha 7S III scores 8.0/10 versus 5.5/10 for FX6 — 4K recording.
What's the resolution difference between the Alpha 7S III and FX6?
Alpha 7S III is 12.1 MP and FX6 is 10.2 MP, so the Alpha 7S III captures more detail for cropping and large prints.
Do the Alpha 7S III and FX6 have in-body image stabilization?
Alpha 7S III has 5.5-stop in-body image stabilization, while fX6 does not have IBIS.
What's the weight difference between the Alpha 7S III and FX6?
Alpha 7S III weighs 699 g and FX6 weighs 890 g, so the Alpha 7S III is 191 g lighter.
Do the Alpha 7S III and FX6 record 4K video?
Alpha 7S III: 4K up to 120p. FX6: 4K up to 120p.
Are the Alpha 7S III and FX6 weather sealed?
Alpha 7S III: Yes. FX6: Yes.
Which has better battery life?
Rated battery life is 600 shots (CIPA) for the Alpha 7S III and 520 shots for the FX6, giving the Alpha 7S III the edge.
How much does each cost?
Alpha 7S III launched at $3,499 and FX6 at $5,999. The Alpha 7S III is $2,500 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.