Panasonic LUMIX S 20mm F2.5 vs Sirui Swift 20mm F2.4 (L-Mount)
The Panasonic is 70g lighter. The Sirui has an aperture ring and cost $349 less at launch.
Key differences
- The Panasonic is 70g lighter (142g vs 212g).
- The Sirui is faster: f/2.4 vs f/2.5 (≈0.1 stops more light).
- At launch the Sirui cost $349 less ($149 vs $498).
- For close-ups the Panasonic reaches 0.15× vs 0.14×.
Which to choose
- LUMIX S 20mm F2.5
Choose it for:
- +The lightest option: 142g, 70g less than the next
- Swift 20mm F2.4 (L-Mount)
Choose it for:
- +A physical aperture ring
- +The lowest launch price: $149, $349 less
Computed from published specs, confirmed launch prices and, where every lens has at least two reviews, review scores.
Panasonic
LUMIX S 20mm F2.5
- Mount
- L-Mount (FF)
- L-Mount (FF)
- Focal length
- 20mm
- 20mm
- Max aperture
- F2.5
- F2.4◆
- Weight
- 142g◆
- 212g
- Dimensions ⌀ × L
- 69.4 × 40.9mm
- 69.5 × 60.3mm
- Volume
- 155 cm³◆
- 229 cm³
- Density
- 0.92 g/cm³
- 0.93 g/cm³
- Filter thread
- ⌀62mm
- ⌀58mm
- Min focus
- 0.18m◆
- 0.20m
- Max magnification
- 0.15×◆
- 0.14×
- Elements / groups
- 11 / 9
- 11 / 9
- Aperture blades
- 7
- 9◆
- Focus drive
- Stepping Motor
- STM
- Stabilisation
- —
- —
- Weather sealed
- Yes
- Yes
- Aperture ring
- —
- Yes
- Released
- 2026
- 2026
- MSRP (USD)
- $498
- $149◆
- Sharpness
- 7.6
- —
- Bokeh Rendering
- 7.0
- —
- Autofocus Speed
- 8.3
- —
- Flare Resistance
- 6.4
- —
- Build / Sealing
- 8.2
- —
- Value / Size
- 7.8
- —
Performance overlay
- LUMIX S 20mm F2.5
- Swift 20mm F2.4 (L-Mount)
◆ marks the best value in a row. Scores are 0–10 editorial ratings.