Canon TS-E 24mm f/3.5 L - Review / Test Report - Analysis |
Lens Reviews -
Canon EOS (APS-C)
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Distortion
The lens shows slight barrel distortion. Nothing extreme but measurable.
Vignetting
The EOS 350D is an APS-C DSLR so it takes advantage of the sweet spot of full
format lenses such as the TS-E 24mm L. In its default setting the lens
produces a medium medium degree of vignetting at f/3.5. Stopping down to
f/5.6 reduces the problem to an almost negligible degree. This is good
but not overly impressive due to the relatively large front-element and
the quite moderate max. aperture. If you take advantage of the shift mechanism
to its most extreme setting the problem gets more pronounced exceeding
1EV which can be quite disturbing. Fortunately it's only a problem at very
large aperture settings.
MTF (resolution)
The lens was able to produce good resolution figures under lab conditions
with a quite even performance from f/3.5 to f/11. However, relative to the
price tag of the lens and regarding the L designation the performance
figures are slightly disappointing.
Beyond the MTF data the lens suffers a little from low contrast when using the shift function.
The edge performance seems to decrease as well - unfortunately there was no time to confirm
this impression in the lab.
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 (CA)
The average pixel width of chromatic aberrations (color shadows at harsh contrast transitions)
is close to 1 pixel which means that the issue can be visible at times without being extreme.
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