Sony Alpha A7S III vs Sony FX3
Sony FX3 has the edge on paper, but the right choice depends on what you shoot. the FX3 is better for travel.
Choose the Alpha A7S III for
- a lower price (from £1,789)
Choose the FX3 for
- a lighter body (640g vs 699g)
- a newer design (2021)
Specs side by side
| Spec | Alpha A7S III | FX3 |
|---|---|---|
| Sensor | Full frame, 12.1MP | Full frame, 12.1MP |
| Mount | Sony FE (full frame) | Sony FE (full frame) |
| Released | 2020 | 2021 |
| Burst | 10 fps | 10 fps |
| Readout | — | — |
| Max ISO | 409,600 | 102,400 |
| Stabilisation | In-body | In-body |
| Video | 4K 120p 10-bit | 4K 120p |
| Weather sealed | Yes | Yes |
| Viewfinder | Electronic | None |
| Weight | 699 g | 640 g |
| Battery | Sony NP-FZ100 | Sony NP-FZ100 |
| Card slots | 2×CFexpress A/SD | 2×CFexpress A/SD |
| New price | £3,389 | £2,999 |
| Used at MPB | £1,789–2,249 | £2,479–2,819 |
| Native lenses in our database | 105 (82 third-party) | 105 (82 third-party) |
Which is better for…
| Use | Better choice |
|---|---|
| Beginner-friendly | About equal |
| Everyday & travel | FX3 |
| Portraits | About equal |
| Landscape | About equal |
| Wildlife & animals | About equal |
| Sports & action | About equal |
| Astrophotography | About equal |
| Vlogging & video | About equal |
| Vintage / film look | About equal |
Based on the specs that matter most for each type of photography: burst and readout for action, resolution for landscapes, sensor size and low light for portraits and astro, video and weight for vlogging.
Lenses and running costs
Both cameras use the Sony E / FE mount, so lenses move between them. They share the same battery (Sony NP-FZ100).
Alpha A7S III compatible lenses → · FX3 compatible lenses → ·
Frequently asked questions
Is the Sony Alpha A7S III better than the Sony FX3?
It depends on your priorities. The Alpha A7S III offers a lower price (from £1,789); the FX3 offers a lighter body (640g vs 699g), a newer design (2021).
Which is better for video, the Alpha A7S III or the FX3?
They are closely matched for video (4K 120p 10-bit vs 4K 120p); stabilisation and lens choice will decide it.
Which is cheaper, the Alpha A7S III or the FX3?
The Alpha A7S III costs £3,389 new and from £1,789 used at MPB; the FX3 costs £2,999 new and from £2,479 used (checked 5 November 2026).
Can I use Sony Alpha A7S III lenses on the FX3?
Yes. Both use the Sony E / FE mount.