You asked
Is the tamron 17 50mm f 4 di iii vxd worth it?
Here is what the site says about that.
From Tamron 17-50mm f/4 Di III VXD: Tamron 17-50mm f/4 Di III VXD: A zoom lens by Tamron for Full frame cameras, 17-50mm f/4. A light constant f/4 standard zoom that starts at 17mm. Specs - Maker: Tamron - Focal length: 17-50mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 17-50mm. - On APS-C (Sony E): like 26-75mm ...
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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