You asked
Is the sigma 16 28mm f 2 8 dg dn contemporary worth it?
Here is what the site says about that.
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 Sensor sizes: Is full frame worth it?: For low light, events, and portraits with very shallow depth of field, yes. For travel, street, wildlife on a budget, and most hobby photography, a good APS-C camera with good lenses is enough, and you'll carry it more. Lenses and light matter more than the last stop of sensor performance.
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