Sigma 16 28mm f 2 8 dg dn contemporary vs tamron 17 28mm f 2 8 di iii rxd?

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From Sigma 16-28mm f/2.8 DG DN Contemporary: Sigma 16-28mm f/2.8 DG DN Contemporary: A zoom lens by Sigma for Full frame cameras, 16-28mm f/2.8. Specs - Maker: Sigma - Focal length: 16-28mm (zoom) - Maximum aperture: f/2.8 - 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 marked, 16-28mm. - On APS-C (Sony E, L-Mount): like 24-42mm on full frame; f/2.8 gives about the ...

From Tamron 17-28mm f/2.8 Di III RXD: Tamron 17-28mm f/2.8 Di III RXD: A zoom lens by Tamron for Full frame cameras, 17-28mm f/2.8. Specs - Maker: Tamron - Focal length: 17-28mm (zoom) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 17-28mm. - On APS-C (Sony E): like 26-42mm on full frame; f/2.8 gives about the depth of field ...

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