Although Canon have made lots of 70-300mm’s over the years, it’s easy to forget that they’ve also made a couple of 100-300mm zooms. Does sacrificing a little bit of zoom range mean higher performance? From what I’d read of this lens before starting the test - owners seemed to think so. Although not particularly lightweight at 535g the Canon EF 100-300 f4.5-5.6 USM is no problem to carry around all day, and feels reasonably well made, with a metal mount and a smooth zooming action. Like all Canon lenses in this price range the lens hood is an expensive extra but I would say it’s essential. The required hood is an ET65II. Filter mount is 58mm and the front of the lens does rotate, but only by a few degrees when zooming, not when focusing.

One definite advantage of the lower zoom range appears to be less distortion or vignetting - I didn’t notice any of either.

Test results overall, I’d say were excellent.