Canon 75-300mm USM III Interchangeable Lens Review

Specifications

• Focal length 75-300mm
• Aperture f/4-5.6
• Angle of view -8°
• Filter size / type 58mm
• Construction Elements/groups 13 elements in 9 groups
• Focusing type USM rotating
• Closest focus 1.5m
• Weight 0.48kg
• Dimensions (Dia x length) 71x122.1mm
• Mounts available Canon,
• Tripod bush No
• Price £189

Build and Handling
This relatively lightweight lens has more than three quarters of the lens barrel taken up with the zoom ring. A wide (38mm) band of ribbed rubber grip takes up about half of this and the ring is marked at 75, 100, 135, 200 and 300mm markings. At the front of the lens is a narrow ring for manual focussing. The front 10mm of the lens is the part holding the front element, which both extends and rotates during focussing. Zooming also extends this element so that when zoomed and close focussed, the lens is some 70mm longer.

Focussing was quiet, down to the USM motor but not exceptionally fast and although it was good at the wide end, it often hunted at the long end, especially with low contrast subjects and occasionally with extra high contrast ones too!

Manual over-ride was not possible when the lens was set to autofocus and when set to manual, by way of a switch on the left side of the barrel, the focus ring became loose and easy to turn. Although narrow, this ring was still relatively easy to use.

The build quality was reasonable for a lens in this price bracket, although still a little plasticy to inspire confidence.

Optical Quality
Canon has a reputation for producing good lenses and it this respect the lens was a little disappointing. Usable at the short end, the performance dropped significantly towards the longer focal length, becoming decidedly soft fully extended. Given that a number of people buying this lens will be doing so for the reach of the long end, I would like to have seen a bit better performance there. Distortion however, was negligible, with a slight pincushion at the short end, which disappeared soon after the onset of zooming and did not turn into barrel at the longer end. Chromatic aberration was not a concern, possibly disguised by the softness! If you are only printing to A4, then you may just get away with this lens.

Focusing on the Canon EOS 1D was good	The closest focus is only 1.5m
At 75mm you get a reasonable performance	The closest focus is only 1.5m

Click on each comparision photo below to view full size versions

75-300mm set at 75mm at f/4	75-300mm set at 300mm at f/5.6
75-300mm set at 75mm at f/8	75-300mm set at 300mm at f/8

Below is our lens test data. To find out how to use these graphs look at this article: How we test lenses

DxOMark provides objective, independent, RAW-based image quality performance data for lenses and digital cameras to help you select the best equipment to meet your photographic needs. Visit the DxOMark website for tests performed on the Canon 75-300mm USM III.

Verdict
Despite its drawbacks, this is still quite a usable budget telephoto lens. It does not carry much of a weight penalty, and therefore has more chance of being in the bag when you want the extra reach that it offers. In its class, its biggest drawbacks are the close focus ability being poor and softness at the longer end.

In summary the main positive points of the Canon 75-300mm USM III are:
Autofocus is quiet and fairly responsive.
Light weight and easy handling
Distortions well controlled
Price

Negative points are:
Sharpness falls off towards the long end
Rotating front element
Narrow focus ring (Minor point)

Check the latest price of the Canon 75-300mm USM III here