Canon ef 17 40mm f 4l usm vs tamron sp 15 30mm f 2 8 di vc usd?

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From Tamron SP 15-30mm f/2.8 Di VC USD: Tamron SP 15-30mm f/2.8 Di VC USD: A zoom lens by Tamron for Full frame cameras, 15-30mm f/2.8. Specs - Maker: Tamron - Focal length: 15-30mm (zoom) - Maximum aperture: f/2.8 - 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, 15-30mm. - On APS-C (Nikon F): like 22-45mm on full frame; f/2.8 gives about ...

From Canon EF 17-40mm f/4L USM: Canon EF 17-40mm f/4L USM: A zoom lens by Canon for Full frame cameras, 17-40mm f/4. An older, light L wide zoom that is plentiful used. Specs - Maker: Canon - Focal length: 17-40mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 17-40mm. - On APS-C (Canon) (Canon EF): like ...

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