Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Panasonic - Lumix S5IIX | Sony - FX3 |
|---|---|---|
| XLR input | false | true |
| Max video | 6K | 4K120 |
Between the Lumix S5IIX and FX3, the Lumix S5IIX comes out ahead in max video, while the FX3 wins on xlr input. Overall, the Lumix S5IIX scores 67.2 and the FX3 scores 63.1 on our Mars Score.
Which should you buy?
The Lumix S5IIX edges ahead on the Mars Score (67.2 vs 63.1), but the 4.1-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the Lumix S5IIX if you care most about max video. The biggest gaps in its favor are max video. The single most decisive one: Max video: 6K (vs 4K120).
Pick the FX3 if you care most about xlr input. Its strongest claims are xlr input. The single most decisive one: Has XLR input.
Both ship with comparable optical zoom, sensor size, so those specs do not separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.
Which should you buy: Panasonic - Lumix S5IIX or Sony - FX3?
Panasonic - Lumix S5IIX leads the current Mars Score by 4.1 points.The more useful decision is the trade-off behind that result: compare max video against the way you will actually use the product.
Choose Panasonic - Lumix S5IIX if…
Panasonic - Lumix S5IIX has the measurable edge on max video.
Choose Sony - FX3 if…
Sony - FX3 has the measurable edge on has xlr input.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Panasonic - Lumix S5IIX wins
- ▲Max video: 6K (vs 4K120).
Why Sony - FX3 wins
- ▲Has XLR input.
Spec comparison
Video
| Spec | Panasonic - Lumix S5IIX | Sony - FX3 |
|---|---|---|
| Max video | 6Klead | 4K120 |
| Optical zoom | 0 | 0 |
| Sensor sizeⓘ | Full Frame | Full Frame |
Audio
| Spec | Panasonic - Lumix S5IIX | Sony - FX3 |
|---|---|---|
| XLR input | false | truelead |
| Headphone jack | true | true |
Design
| Spec | Panasonic - Lumix S5IIX | Sony - FX3 |
|---|---|---|
| Weight | 740 g | 715 glead |
| Articulating screen | true | true |