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Is the sigma 20 60mm f 2 8 4 dg contemporary good on aps c?

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From Sigma 20-60mm f/2.8-4 DG Contemporary: Sigma 20-60mm f/2.8-4 DG Contemporary: A zoom lens by Sigma for Full frame cameras, 20-60mm f/2.8-4. A standard zoom that starts at a true ultra-wide 20mm. Specs - Maker: Sigma - Focal length: 20-60mm (zoom) - Maximum aperture: f/2.8-4 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E, L-Mount): as ...

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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