Canon ef 180mm f 3 5l macro usm vs tamron 90mm f 2 8?

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 Focal length converter: Aperture and depth of field: The f-number sets exposure, and that doesn't change with sensor size: f/2.8 gives the same brightness on a phone as on medium format. Depth of field does change. At the same framing, multiply the f-number by the crop factor to get the full-frame aperture with the same depth of field: f/1.8 on APS-C gives about the background blur of f/2.7 on full frame, and f/1.8 on Micro Four Thirds about ...

Quoted from this site's pages.