Is the leica apo telyt m 135mm f 3 4 hard to focus manually?

The Leica APO-Telyt-M 135mm f/3.4 is manual focus only, with no autofocus. At 135mm, precision matters, so I'd say it's not difficult, but it does take practice. The lens page notes that precise focusing is easier with live view or an EVF, so pair it with a body that offers one. Many of the Leica M bodies that fit it are listed on the lens page, and you can check each one's camera page for its viewfinder options. For portraits at this focal length, the portrait guide explains why it suits headshots.

Written by Claude from this site's pages.