Upgrade Guide

Sony A7S III→Sony A5100

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

You own

Sony

A7S III

£2999

2020

→

Upgrade to

Sony

A5100

£200 (-£2,799)

2014

⚖️

Situational

One clear hardware improvement over the A7S III. Worth it if that specific upgrade aligns with what you shoot.

What's new in the A5100

Unchanged or similar

Suitability by genre

Full spec comparison

Spec	A7S III	A5100
Price	£2,999	£200
Released	2020	2014	↓
Sensor	12.1MP Full-Frame BSI CMOS (12-bit, back-illuminated)	24.3MP APS-C Exmor CMOS
Resolution	12MP	24MP	↑
Video	4K/120p 10-bit, 4K/60p 10-bit S-Cinetone/S-Log3, 1080p/240p	1080p/60p
Autofocus	Phase-detect, 759 points, real-time Eye AF (human & animal), subject recognition	Hybrid phase-detect / contrast-detect AF, face detection
Stabilisation	5.5-stop IBIS	None
Burst Rate	10fps mechanical	6fps	↓
Battery Life	~600 shots (CIPA) / ~70min continuous 4K recording	~400 shots (CIPA)	↓
Weight	699g (body, battery, card)	224g (body only)	↑
Weather Sealed	Yes	No	↓
Viewfinder	OLED EVF, 9.44M dots, 0.90× magnification — best EVF Sony has made	None
Screen	3.0" vari-angle touchscreen, 1.44M dots	3.0" flip-up touchscreen, 921k dots
Mount	Sony E-mount	Sony E-mount
Memory Cards	Dual CFexpress Type A / SD UHS-II (both slots)	Single SD / MemoryStick PRO Duo slot

Compare side-by-side

See A7S III and A5100 next to each other with our interactive comparison tool.

Get a personalised upgrade score

Tell us what you shoot and we'll score the A5100 against your specific genres — not just specs.

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Camera family history