What is the leica tri elmar m 16 18 21mm f 4 asph good for?

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From Leica Tri-Elmar-M 16-18-21mm f/4 ASPH: Leica Tri-Elmar-M 16-18-21mm f/4 ASPH: A zoom lens by Leica for Full frame cameras, 16-21mm f/4. Three ultra-wide focal lengths in one lens. Specs - Maker: Leica - Focal length: 16-21mm (zoom) - Maximum aperture: f/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, 16-21mm. Cameras it fits - Leica M9: Full frame ...

From Landscape: Lenses: - A wide zoom, around 16-35mm on full frame or 10-24mm on APS-C, is the classic landscape lens: big skies, strong foregrounds. - A standard zoom, 24-70mm or similar, covers most scenes. - A telephoto zoom, 70-200mm or longer, is underrated: it picks out layers of hills, a lone tree, or light on a distant ridge. You don't need fast apertures for landscapes, since you'll usually shoot between f/8 and ...

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