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Tamron AF 17-35mm f/2.8-4 Di LD Aspherical IF (Nikon) - Review / Lab Test Report - Analysis |
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Lens Reviews -
Nikon / Nikkor (APS-C)
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Page 2 of 2
Distortion
At 17mm the Tamron shows a very pronounced degree of barrel distortion (2.7%) which
eases continuously towards the long end of the zoom range. At 35mm the lens is basically
free of distortion.
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Move the mouse cursor over the focal length text marks below to observe the respective distortion
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| 17mm |
24mm |
35mm |
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The chart above has a real-world size of about 120x80cm.
Vignetting
Full frame lenses enjoy a sweet spot advantage on APS-C DSLRs such as the
Nikon D200 and the amount of vignetting is quite low accordingly.
At 17mm @ f/2.8 vignetting is slightly more pronounced at around 0.7EV but relatively
speaking this is already pretty good. As usual it helps a little to stop
down but typical for wide-angle lenses you can't eliminate the issue completely.
However, from f/4 onwards it should be rarely field-relevant - same goes for the
other focal lengths.
MTF (resolution)
The Tamron produced a very good performance in the MTF lab. The center
performance is generally excellent at all focal lengths and throughout
the tested aperture settings. At 17mm and 24mm and wide-open aperture
the borders aren't quite as good but they easily reach very good quality
from f/4 onwards. The lens shows a moderate degree of field curvature
throughout the range.
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 (CAs)
Typical for many wide to ultra-wide lenses chromatic aberrations (color shadows at harsh
contrast transitions) are quite pronounced. This is especially true for the 24mm
setting where CAs peak at around 1.8px on the average at the image borders at medium
aperture settings.
Please note that lateral CAs can be corrected via various imaging applications.
Verdict
The Tamron AF 17-35mm f/2.8-4 Di LD Aspherical IF SP proved to be a very decent
standard zoom lens within the tested APS-C DSLR scope. The resolution figures are
excellent in the center of the image and good to very good at the borders.
Distortions are very pronounced at 17mm but very moderate otherwise. Typical
for full frame lenses vignetting is very well controlled. CAs are a little on the
high side specifically at 24mm. The build quality is generally pretty good but the
direct competition does a little better job in this respect. When shopping for a
new lens the Tamron AF 17-50mm f/2.8 SP may be a tad better and more versatile in
terms of focal length range but without full format capabilities. If you prefer to
have a lens living in both camps the AF 17-35mm f/2.8-4 Di SP may be still worth a
deeper look.
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