Leica APO-Summicron-SL 50mm f/2 ASPH vs Sigma 45mm f/2.8 DG DN Contemporary
Leica APO-Summicron-SL 50mm f/2 ASPH has more in its favour on paper. The APO-Summicron-SL 50mm f/2 ASPH gathers more light for low light and background blur; the 45mm f/2.8 DG DN Contemporary is lighter and cheaper.
Choose the APO-Summicron-SL 50mm f/2 ASPH for
- a brighter maximum aperture (f/2, about 1.0 stops more light)
- weather sealing
Choose the 45mm f/2.8 DG DN Contemporary for
- less weight (215g vs 740g)
- a lower price (about £320 vs £2,500)
| APO-Summicron-SL 50mm f/2 ASPH | 45mm f/2.8 DG DN Contemporary | |
|---|---|---|
| Brand | Leica | Sigma |
| Focal length | 50mm | 45mm |
| Maximum aperture | f/2 | f/2.8 |
| Weight | 740 g | 215 g |
| Stabilisation | No | No |
| Weather sealing | Yes | No |
| Filter size | 67mm | 55mm |
| Made for | Full frame | Full frame |
| New price | £4,500 | £499 |
| Used at MPB (L-Mount) | £2,479–£2,519 | £309–£324 |
More lens comparisons
See all L-Mount cameras and lenses.
Frequently asked questions
Is the Leica APO-Summicron-SL 50mm f/2 ASPH better than the Sigma 45mm f/2.8 DG DN Contemporary?
The APO-Summicron-SL 50mm f/2 ASPH offers a brighter maximum aperture (f/2, about 1.0 stops more light), weather sealing; the 45mm f/2.8 DG DN Contemporary offers less weight (215g vs 740g), a lower price (about £320 vs £2,500).
Which is better value, the APO-Summicron-SL 50mm f/2 ASPH or the 45mm f/2.8 DG DN Contemporary?
On L-Mount, the Sigma 45mm f/2.8 DG DN Contemporary costs about £320 against about £2,500 for the Leica APO-Summicron-SL 50mm f/2 ASPH (MPB used where listed, otherwise new; checked 5 November 2026).
Is f/2 worth it over f/2.8?
f/2 gathers about 1.0 stops more light, which helps indoors, at night and for background blur. If you mostly shoot in good light, the slower lens is usually lighter and cheaper.
Do both lenses fit the same cameras?
Both are available for L-Mount (and other mounts: Sony E / FE).