Panasonic LUMIX S 40mm F2 vs Sirui Swift 40mm F2.2 (L-Mount)
The Panasonic is 71g lighter. The Sirui has an aperture ring and cost $251 less at launch.
Key differences
- The Panasonic is 71g lighter (144g vs 215g).
- The Panasonic is faster: f/2 vs f/2.2 (≈0.3 stops more light).
- At launch the Sirui cost $251 less ($149 vs $400).
- For close-ups the Panasonic reaches 0.17× vs 0.14×.
Which to choose
- LUMIX S 40mm F2
Choose it for:
- +The lightest option: 144g, 71g less than the next
- Swift 40mm F2.2 (L-Mount)
Choose it for:
- +A physical aperture ring
- +The lowest launch price: $149, $251 less
Computed from published specs, confirmed launch prices and, where every lens has at least two reviews, review scores.
Panasonic
LUMIX S 40mm F2
- Mount
- L-Mount (FF)
- L-Mount (FF)
- Focal length
- 40mm
- 40mm
- Max aperture
- F2◆
- F2.2
- Weight
- 144g◆
- 215g
- Dimensions ⌀ × L
- 69.4 × 40.9mm
- 69.5 × 60.0mm
- Volume
- 155 cm³◆
- 228 cm³
- Density
- 0.93 g/cm³
- 0.94 g/cm³
- Filter thread
- ⌀62mm
- ⌀58mm
- Min focus
- 0.30m◆
- 0.40m
- Max magnification
- 0.17×◆
- 0.14×
- Elements / groups
- 7 / 6
- 11 / 8
- Aperture blades
- 7
- 9◆
- Focus drive
- Stepping Motor
- STM
- Stabilisation
- —
- —
- Weather sealed
- Yes
- Yes
- Aperture ring
- —
- Yes
- Released
- 2026
- 2026
- MSRP (USD)
- $400
- $149◆
- Sharpness
- 8.3
- —
- Bokeh Rendering
- 7.0
- —
- Autofocus Speed
- 8.3
- —
- Flare Resistance
- 8.4
- —
- Build / Sealing
- 8.2
- —
- Value / Size
- 9.0
- —
Performance overlay
- LUMIX S 40mm F2
- Swift 40mm F2.2 (L-Mount)
◆ marks the best value in a row. Scores are 0–10 editorial ratings.