Is the sigma 60 600mm f 4 5 6 3 dg os hsm sports good for portraits?

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From Sigma 60-600mm f/4.5-6.3 DG OS HSM Sports: Sigma 60-600mm f/4.5-6.3 DG OS HSM Sports: A zoom lens by Sigma for Full frame cameras, 60-600mm f/4.5-6.3. Specs - Maker: Sigma - Focal length: 60-600mm (zoom) - Maximum aperture: f/4.5-6.3 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Canon EF, Nikon F - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon F): as marked, 60-600mm. - On APS-C (Nikon F): like ...

From Sigma 60-600mm f/4.5-6.3 DG DN OS Sports: Sigma 60-600mm f/4.5-6.3 DG DN OS Sports: A zoom lens by Sigma for Full frame cameras, 60-600mm f/4.5-6.3.

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