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Canon EF 70-200mm f/2.8 USM L IS II - Full Format Review / Test Report - Analysis |
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Lens Reviews -
Canon EOS (Full Format)
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Page 2 of 3
Distortion
The Canon EF 70-200mm f/2.8 USM L IS II does a good job with respect to distortion but the
situation is still a little worse compared to prime lenses. The Canon lens produces a slight
degree of barrel distortion at 70mm, slight pincushion distortion at 135mm and slight to moderate
pincushion distortion at 200mm. The latter may be visible in very critical field situations.
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Move the mouse cursor over the focal length text marks below to observe the respective distortion
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| 70mm |
135mm |
200mm |
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Vignetting
Vignetting is a critical topic for most lenses when used on full format DSLRs but it's not an overly
significant issue for the EF 70-200mm II. The problem is still visible at around 1.3EV at max. aperture and 135mm/200mm
but this still comparatively moderate. The vignetting is basically negligible from f/5.6 onwards.
MTF (resolution)
The EF 70-200mm f/2.8 USM L IS II delivered awesome resolution figures in the MTF lab. The center
resolution is excellent from f/2.8 to f/8 throughout the tested focal lengths and only diffraction
effects are limiting it to very good figures at f/11. The border and corner performance is also
very good, sometimes even excellent. The quality is only marginally worse at the 200mm setting compared
to the shorter focal lengths.
Field curvature is basically non-existent.
Please note that the MTF results are not directly comparable across the different systems!
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 the MTF50 figures you may check out the corresponding Imatest Explanations
Chromatic Aberrations
The Canon lens manages to show an excellent behavior regarding lateral chromatic aberrations (color shadows
at harsh light transitions). At less than 0.7px at the image borders it is usually nothing to worry about in
field conditions.
Bokeh
The EF 70-200mm f/2.8 USM L IS II is a "fast" lens so the quality of the bokeh is a major aspect here.
Out-of-focus highlights have a basically perfect circular shape with basically no outlining from f/2.8 to f/5.6.
This is true for most of the image frame but in the image corners the circular shape is somewhat "cut" just like
a "cat's eye" - this originates in the vignetting at f/2.8 so this problem eases when stopping down.
The quality of the blur is good for a zoom lens although the best primes remain a touch better here.
These sample portions were taken at ~140mm.
Bokeh Fringing / Longitudinal Chromatic Aberrations (LoCA)
Bokeh fringing at large aperture is a problem which is often not well corrected but the Canon lens
is capable of delivering a good albeit not perfect characteristic here. If you look hard (on a good
screen) you may spot some green and purple traces at large apertures. They're not dominant but
visible.
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Move the mouse cursor over the f-stop marks below to observe the respective LoCAs
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| f/2.8 |
f/4 |
f/5.6 |
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These sample portions were taken at ~140mm.
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