You asked

Is the leica noctilux m 50mm f 1 2 asph hard to focus manually?

Here is what the site says about that.

From Leica Noctilux-M 50mm f/1.2 ASPH: Leica Noctilux-M 50mm f/1.2 ASPH: A prime lens by Leica for Full frame cameras, 50mm f/1.2. A remake of the 1966 original Noctilux. Specs - Maker: Leica - Focal length: 50mm (prime) - Maximum aperture: f/1.2 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 50mm. Cameras it fits - Leica M9: Full frame ...

From Leica Noctilux-M 50mm f/0.95 ASPH: Leica Noctilux-M 50mm f/0.95 ASPH: A prime lens by Leica for Full frame cameras, 50mm f/0.9. The fastest M lens; heavy, and focus is very thin wide open.

Quoted from this site's pages.

From these pages