Canon's fast rangefinder tele — 100mm f/2 in Leica Thread Mount, manual focus.
The Canon 100mm f/2 is a fast telephoto rangefinder lens made in Japan for the 39mm Leica screw thread. Released at the end of the 1950s, it was one of the faster 100mm lenses in Canon's rangefinder line and a larger, more ambitious optic than the slower screw-mount teles. It served Leica-thread and Canon rangefinder bodies for portraits and low light.
This is a manual-focus, rangefinder-coupled Leica Thread Mount lens with a 100mm focal length and a maximum aperture of f/2. The mount is the 39mm Leica screw thread (LTM / L39 / M39). Focus and aperture 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.
A 100mm at f/2 is a fast portrait and available-light telephoto, giving strong subject separation and shallow depth of field with compressed perspective. Fast teles of this generation render smoothly wide open and sharpen on stopping down. It suits portraits, low-light shooting and picking out distant subjects.
On the used market, inspect for haze, fungus and balsam separation in the cemented groups. Check the coatings for cleaning marks and wear, look for oily aperture blades, and confirm the focus helicoid is smooth. Rangefinder-coupling accuracy is critical for a fast 100mm, so test it carefully on a body. It adapts well to Leica M via M39-to-M and to mirrorless using M39-to-E, M39-to-Z or M39-to-RF adapters.