Voigtlander Nokton 50mm f/1.5 II

This is the fast Leica fifty for people who think a Summilux ASPH costs absurd money. Cosina builds it under the Voigtlander name, and the Nokton 50mm f/1.5 II gives you most of what a fast normal lens does on an M body for a fraction of what the Summilux runs. The Nokton name is not marketing nostalgia either; Voigtlander used it on its fast double-Gauss design back in the 1950s, and this is a modern double-Gauss with an aspherical element doing the heavy lifting.

Wide open at f/1.5 it has a look. Center sharpness is already good, but there is a faint glow off specular highlights and skin, the spherical-aberration softness that fast fifties trade in. Stop down to f/2.8 and it snaps into proper bite; by f/4 it is sharp across most of the frame. The bokeh is smooth and rounded, with the cat's-eye stretching you expect toward the edges wide open. Contrast is healthy without going clinical, and color is neutral with a slight warmth that suits people.

It is small. That matters on a rangefinder, where the lens sits in the corner of the frame and you do not want a fat barrel blocking the finder. The classic styling on the II, the knurled focus ring and the black or silver finish, is the point for a lot of buyers. This is street and documentary glass first, the lens that lives on a film M or an M10 and gets worked from f/1.5 to f/5.6 all day.

The honest weakness is the wide-open frame edge. There is field curvature, the corners trail behind the center, and clinically flat edge-to-edge resolution at f/1.5 is not what this lens is for. Voigtlander's own APO-Lanthar 50mm f/2 out-resolves it comfortably, and the Leica Summilux ASPH does too. You are buying rendering, not a test chart.

Cross-shopped against the Zeiss C Sonnar 50mm f/1.5, the Nokton wins on focus consistency. Sonnar designs are notorious for focus shift as you stop down; this double-Gauss handles it far better. Below it sit the budget fast fifties from 7Artisans and TTArtisan, which cost less and render rougher. The Nokton splits the difference, and that is why it keeps selling. One note for film shooters: at f/1.5 it pulls in enough light that in a dim bar or at blue hour you can meter wide open in Zone Light Meter and still hand-hold a usable shutter speed.