Canon EF 70-300mm f/4-5.6 USM IS - Full Format Lab Test / Review - Analysis
Lens Reviews -
Canon EOS (Full Format)
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The Canon EF 70-300mm IS has a sub-average distortion characteristic for a standard tele zoom lens. It produces a slight to moderate barrel distortion (~1.2%) at 70mm and slight to moderate pincushion distortions at 200mm (~1.1%). However, at 300mm the situation worsens to quite heavy pincushion distortion (2.6%) which is unusual in this class.
Move the mouse cursor over the focal length text marks below to observe the respective distortions
Vignetting is comparatively well controlled at around 1EV at max. aperture. This is visible but we've seen a lot worse in our full format tests.
The resolution characteristic of the EF 70-300mm IS varies across its zoom range. At 70mm it is capable of delivering very good to excellent
results across the image frame and that's straight from f/4. As expected there's a quality drop when zooming towards the long end of the range.
However, at 200mm the results are still good to very good at the image borders and very good at the center. At 300mm it's getting a tad worse
primarily in the image corners.
Below is a simplified summary of the formal findings. The chart shows line widths per picture height (LW/PH)
which can be taken as a measure for sharpness. If you want to know more about it you may check out the corresponding
The lens produced a varying but comparatively low degree of chromatic aberrations (color shadows at
harsh contrast transitions) at the image borders. The average CA pixel width remains well
below 1 pixel at 70mm and 200mm. The problem increases to ~1.4px at 300mm but that's still decent
within the full format scope.
The Canon EF 70-300mm f/4-5.6 USM IS is a decent performer and a great value offer. It is capable of delivering
superb results at 70mm (for a slow speed lens) and it's still pretty good at 200mm and even 300mm. The vignetting
is comparatively moderate even at max aperture. Lateral CAs are quite well controlled. The amount of distortion
is about average between 70mm and 200mm but at 300mm the rather heavy amount of pincushion distortion can be
disturbing in some situations (e.g. architecture photography). The build quality is about typical for a consumer lens
but the rotating front element seems a little dated by now. You won't classify the 70-300mm IS as an AF speed demon
but it's reasonably fast compared to similar tele zoom lenses with a conventional AF motor. However, it's one of the
slower AF lenses in the native Canon lineup.