Upgrade Guide

Sony A7 III→Sony FX3

Is it worth upgrading? Spec analysis, key improvements, and our verdict.

You own

Sony

A7 III

£1699

2018

→

Upgrade to

Sony

FX3

£3799 (+£2,100)

2021

⚖️

Situational

One clear hardware improvement over the A7 III. Worth it if that specific upgrade aligns with what you shoot.

What's new in the FX3

Unchanged or similar

Suitability by genre

Full spec comparison

Spec	A7 III	FX3
Price	£1,699	£3,799
Released	2018	2021	↑
Sensor	24.2MP Full-Frame Exmor R BSI CMOS	12.1MP full-frame BSI Exmor R CMOS (same as A7S III)
Resolution	24MP	12MP	↓
Video	4K/30p (6K oversampled), 1080p/120p slow-motion	4K/120p, 4K/60p 10-bit, 12-bit RAW output, S-Log3, S-Cinetone
Autofocus	Phase-detect, 693 points, real-time Eye AF & animal AF	Real-time tracking with subject recognition (human, animal)
Stabilisation	5-axis IBIS, 5 stops	5-axis IBIS — 5 stops
Burst Rate	10fps with AF/AE tracking	10fps mechanical, 10fps electronic
Battery Life	~710 shots (CIPA)	~640 shots (CIPA)	↓
Weight	565g (body, battery, card)	715g body only (with XLR handle)	↓
Weather Sealed	Yes	Yes
Viewfinder	EVF, 2.36M dots, 0.78× magnification	None — monitor/external EVF use only
Screen	3.0" tilting touchscreen, 921k dots	3.0" touchscreen, fully articulating
Mount	Sony E-mount	Sony FE mount (full-frame E-mount)
Memory Cards	Dual SD (UHS-II slot 1, UHS-I slot 2)	Dual CFexpress Type A / SD UHS-II slots

Compare side-by-side

See A7 III and FX3 next to each other with our interactive comparison tool.

Get a personalised upgrade score

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