Overview

The Canon Serenar 135mm f/3.5 I is a solid, all-metal lens with smooth focus and click-stop aperture, though the front element rotates and the aperture ring turns during focusing. Optically, it uses a simple 4-element design that delivers good performance, going head-to-head with Leica 135mm lenses, but exhibits mild issues at long distances. It is light and thin but looks odd on cameras. The lens suits rangefinder users who can manage 135mm focusing, especially with live view or magnifiers, and is affordable ($60–$200).