Voigtländer Nokton Classic 40mm f/1.4 SC
A fast normal prime for Leica M rangefinders, and one of the most quietly useful focal lengths in 35mm. At 40mm, it sits between the 35 and the 50, wide enough for the street, tight enough for a portrait. The f/1.4 aperture opens up low light and gives you real control over depth of field, and at 175 grams it stays out of the way on the front of an M body. The SC in the name stands for single coated, as oppose d to the multi-coated version of the same optic. It renders with slightly lower contrast and a softer, more classic character, which is exactly what a lot of shooters want on black and white film. If you like a little air in the highlights and a gentler tonal roll-off, this is the coating to reach for. Manual focus only, rangefinder coupled, with a 10-blade diaphragm for smooth out-of-focus areas and a close focus of 0.7m. Leica M mount, 43mm filters. A note on framing: on most M bodies the 40mm brings up the 50mm frame lines, so you compose a touch outside them. On a Leica CL, Minolta CL, or CLE it brings up the correct 40mm frame.