Leica Summicron-SL 50 f/2 ASPH.

The Summicron-SL 50 f/2 ASPH. is Leica's lighter, cheaper alternative to the APO-Summicron-SL 50, announced in February 2023 with the matching Summicron-SL 35. It weighs about 402g, roughly half the APO's weight, is 83mm long, and launched at well under half the APO's US price, which made it the least expensive Summicron-SL prime.

The optical design has 9 elements in 8 groups, with three aspherical elements (six aspherical surfaces) and anomalous partial dispersion glass for colour correction. A linear direct drive handles focus quietly enough for video, close focus is 0.45m (1:7.4), and the magnesium and aluminium barrel is dust and splash protected with Aqua-Dura coated outer elements. It shares its 67mm filter thread and outer dimensions with the Summicron-SL 35, which helps when swapping lenses on a gimbal.