Leica super vario elmarit sl 14 24mm f 2 8 asph vs sigma 16 28mm f 2 8?

Here is what the site says about that.

From Leica Super-Vario-Elmarit-SL 14-24mm f/2.8 ASPH: Leica Super-Vario-Elmarit-SL 14-24mm f/2.8 ASPH: A zoom lens by Leica for Full frame cameras, 14-24mm f/2.8. Specs - Maker: Leica - Focal length: 14-24mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (L-Mount): as marked, 14-24mm. - On APS-C (L-Mount): like 21-36mm on full frame; f/2.8 gives about the depth of field of f/4.2 there. ...

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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