Canon ef 16 35mm f 4l is usm vs tamron 17 35mm f 2 8 4 di osd?

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From Tamron 17-35mm f/2.8-4 Di OSD: Tamron 17-35mm f/2.8-4 Di OSD: A zoom lens by Tamron for Full frame cameras, 17-35mm f/2.8-4. A light, inexpensive wide zoom for full-frame DSLRs. Specs - Maker: Tamron - Focal length: 17-35mm (zoom) - Maximum aperture: f/2.8-4 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Canon EF, Nikon F - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon F): as ...

From Canon EF 16-35mm f/4L IS USM: Canon EF 16-35mm f/4L IS USM: A zoom lens by Canon for Full frame cameras, 16-35mm f/4. Specs - Maker: Canon - Focal length: 16-35mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 16-35mm. - On APS-C (Canon) (Canon EF): like 26-56mm on full frame; f/4 gives about the depth of ...

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