Is the leica apo telyt m 135mm f 3 4 good for portraits?

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From Leica APO-Telyt-M 135mm f/3.4: Leica APO-Telyt-M 135mm f/3.4: A prime lens by Leica for Full frame cameras, 135mm f/3.4. The longest current M lens; precise focusing is easier with live view or an EVF. Specs - Maker: Leica - Focal length: 135mm (prime) - Maximum aperture: f/3.4 - 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, 135mm. ...

From Portraits: The lenses: - 50mm f/1.8. The cheapest great lens in photography, made for almost every mount. On full frame it's a natural, slightly tight view; on APS-C it behaves like a classic 75-80mm portrait lens. If you buy one lens for people, buy this. - 85mm f/1.8. The classic full-frame portrait lens: flattering perspective, soft backgrounds, comfortable working distance. On APS-C, a 56mm f/1.2 to f/1.4 plays the same role. - 35mm ...

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