Canon's compact rangefinder wide — 35mm f/2.8 in Leica Thread Mount, manual focus.
The Canon 35mm f/2.8 is a wide-angle rangefinder lens made in Japan for the 39mm Leica screw thread. It comes from Canon's rangefinder lens line of the later 1950s, by which point the optics carried the Canon name rather than Serenar. It served as a moderately fast, compact 35mm for Leica-thread and Canon rangefinder bodies.
This is a manual-focus, rangefinder-coupled Leica Thread Mount lens with a 35mm focal length and a maximum aperture of f/2.8. The mount is the 39mm Leica screw thread (LTM / L39 / M39). Aperture and focus are set on the barrel by hand. Element count, weight and filter thread are not restated here because they are not verified from the gap data.
The 35mm view is a dependable general-purpose wide for street, travel and documentary shooting, with a natural perspective. The f/2.8 maximum aperture handles overcast days and shaded interiors better than the slower wides. As with most lenses of this vintage, stopping down a stop or two improves edge sharpness and evenness.
On the used market, examine the glass for haze and fungus and the cemented groups for balsam separation. Check the coatings for cleaning marks and wear, look for oily aperture blades, and confirm the focus helicoid is smooth. Test rangefinder-coupling accuracy before buying. The lens adapts well to Leica M with an M39-to-M adapter and to mirrorless via M39-to-E, M39-to-Z or M39-to-RF adapters.