Canon ef 180mm f 3 5l macro usm vs tamron 180mm f 3 5?

Here is what the site says about that.

From Canon EF 180mm f/3.5L Macro USM: Canon EF 180mm f/3.5L Macro USM: A macro lens by Canon for Full frame cameras, 180mm f/3.5. Specs - Maker: Canon - Focal length: 180mm (macro) - Maximum aperture: f/3.5 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 180mm. - On APS-C (Canon) (Canon EF): like 288mm on full frame; f/3.5 gives about the depth of ...

From Sensor sizes: What it costs you: - Size, weight and price, especially of the lenses. A full-frame telephoto is much larger than its APS-C or Micro Four Thirds equivalent. - Less depth of field when you want more of it, for macro or landscape.

Quoted from this site's pages.