Upgrade Guide
Sony FX3→Sony A5100
Is it worth upgrading? Spec analysis, key improvements, and our verdict.
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Situational
One clear hardware improvement over the FX3. Worth it if that specific upgrade aligns with what you shoot.
What's new in the A5100
-
Resolution24MP vs 12MP (+12MP)
Unchanged or similar
-
Weather sealingNot present in new body
-
StabilisationIBIS not present in new body
Suitability by genre
Base scores — computed from verified specs for an enthusiast shooting photo and video. The Upgrade Checker adjusts them for your skill level.
| Genre | FX3 | A5100 | |
|---|---|---|---|
| Portrait | -0.3 | ||
| Street | +2.7 | ||
| Travel | +1.1 | ||
| Wedding & Events | -2.5 | ||
| Vlogging & Video | -1.1 | ||
| Filmmaking | — | ||
| Documentary | -3.9 | ||
| Sports & Action | -0.8 | ||
| Landscape | +0.3 | ||
| Wildlife | -0.3 | ||
| Casual | +0.3 | ||
| Food | -0.8 | ||
| Macro | -0.3 | ||
| Architecture | — | ||
| Astrophotography | -2.0 | ||
| Fun & simple | — |
Full spec comparison
| Spec | FX3 | A5100 | |
|---|---|---|---|
| Price | £3,799 | £200 | |
| Released | 2021 | 2014 | ↓ |
| Sensor | 12.1MP full-frame BSI Exmor R CMOS (same as A7S III) | 24.3MP APS-C Exmor CMOS | |
| Resolution | 12MP | 24MP | ↑ |
| Video | 4K/120p, 4K/60p 10-bit, 12-bit RAW output, S-Log3, S-Cinetone | 1080p/60p | |
| Autofocus | Real-time tracking with subject recognition (human, animal) | Hybrid phase-detect / contrast-detect AF, face detection | |
| Stabilisation | 5-axis IBIS — 5 stops | No stabilisation | |
| Burst Rate | 10fps mechanical, 10fps electronic | 6fps | ↓ |
| Battery Life | ~640 shots (CIPA) | ~400 shots (CIPA) | ↓ |
| Weight | 715g (body only) | 224g (body only) | ↑ |
| Weather Sealed | Yes | Not weather sealed | ↓ |
| Viewfinder | None — monitor/external EVF use only | No viewfinder | |
| Screen | 3.0" touchscreen, fully articulating | 3.0" flip-up touchscreen, 921k dots | |
| Mount | Sony FE mount (full-frame E-mount) | Sony E-mount | |
| Memory Cards | Dual CFexpress Type A / SD UHS-II slots | Single SD / MemoryStick PRO Duo slot |
Compare side-by-side
⚖️ Compare these cameras
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Get a personalised upgrade score
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Tell us what you shoot and we'll score the A5100 against your specific genres — not just specs.
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