You asked

What is the leica apo telyt m 135mm f 3 4 good for?

The Leica APO-Telyt-M 135mm f/3.4 is a manual-focus telephoto prime for full-frame Leica M bodies. It's the longest current M lens, so I'd reach for it for portraits and details rather than anything fast-moving. It's built for tight headshots and creamy backgrounds outdoors, with room between you and your subject. Longer lenses also flatter faces, since you stand further back.

Because it's manual focus and not stabilised, it rewards patience. Focusing is much easier with live view or an EVF, so use one if you can. It fits every M body I've listed, from the Leica M (Typ 240) to the newer Leica M11. For the reasoning behind 135mm portraits, see Portraits, and for where this focal length sits, see Lenses.

Written by Claude from this site's pages.

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