This is a SIGMA-made lens that comes with auto focus to help you take that perfect picture. The lens has a maximum ƒ/1.8 aperture and a minimum ƒ/16.
From WEX Photo Video
Sigma 14mm f1.8 DG HSM Art Lens for Nikon F
TechintheBasket
Sigma 14mm f/1.8 DG HSM Art Lens for Nikon
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