Canon EF 75-300mm f/4-5.6 III USM - £240/$320
Canon markets this lens as an 'affordable telephoto zoom with a lightweight design'. Sure enough, it's more compact and 150g lighter than the Canon EF 70-300mm f/4-5.6 IS USM, but it's also quite lightweight in features.
The USM autofocus is of the cheaper, motor-based variety that lacks full-time manual focus override. The front element also rotates during focusing, which makes the use of filters like circular polarisers a pain. There's no image stabilisation and build quality feels a bit cheap.
As with many Canon lenses, no lens hood is supplied and the official ET-60 hood costs about £20 extra to buy. Another omission is that there's no focus distance scale. The original version of this lens was launched 20 years ago and even the current Mk III edition has been around for 12 years, having done little to transform itself for the digital age.
Despite its USM credentials, autofocus is ponderous and really struggles in dull lighting conditions. Sharpness is a pretty close match to Canon's more expensive 70-300mm IS lens in the 70-200mm region of the zoom range, but drops off more at longer focal lengths.
Distortions are well controlled throughout the zoom range. Colour fringing is a real problem and very noticeable across much of the image frame when shooting at long focal lengths. As a no-frills option, the lens is fairly cheap, but not particularly good value.
Sharpness test
Taken at ISO 200
Very good through most of the zoom range, but sharpness is disappointing at 300mm and hampered by a lack of stabilisation.
Fringing test
Taken at the minimum zoom
There's very little colour fringing at the shorter end of the zoom range but it can be quite extreme between 250mm and 300mm.
Distortion test
Distortion is well controlled overall, and is the lowest in the entire group at the shortest end of the zoom range.
Image test verdict
Sharpness drops off at 300mm where colour fringing also becomes very noticeable, particularly towards the corners of the frame.
