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Tamron AF 10-24mm F/3.5-4.5 SP Di II LD Aspherical IF - Review / Test Report - Analysis |
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Lens Reviews -
Nikon / Nikkor (APS-C)
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Page 2 of 3
Distortion
Ultra wide angle zoom lenses usually show significant barrel distortion at the wide end. This is also the case here, but with a value of 2% it's less pronounced than with some competitors. Unfortunately the Tamron lens shows only slightly less barrel distortion throughout the rest of the zoom range.
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Move the mouse cursor over the focal length text marks below to observe the respective distortion
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| 10mm |
14mm |
18mm |
24mm |
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The chart above has a real-world size of about 120x80cm.
Vignetting
Lenses designed with an reduced image circle for APS-C cameras tend to show a higher degree of vignetting. This is also visible at 10 mm here, where wide open vignetting exceeds one stop and even stopped down remains well above half a stop. However, at all other focal lengths of the zoom range vignetting is actually well controlled.
MTF (resolution)
The lens showed a mixed performance in the lab. At 10 mm the center resolution wide open is already very good and excellent stopped down. The borders follow a bit behind with good resolution wide open and very good stopped down. The extreme corners are disappointing, though, very soft wide open and at f/5.6. Stopped down to f/8 and f/11 (which is what you'll most likely want to do anyway for landscapes) they just reach very good values.
The situation is hardly any different at 14 and 18 mm. Wide open the extreme corners are poor, but they no longer reach very good levels stopped down. Only at 24 mm the lens showed better performance with excellent center and very good border resolution throughout the aperture range and good to very good extreme corners.
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)
At 10 mm the lens shows a large amount of lateral CAs (color shadows at harsh contrast transitions) with 2.4 pixels wide open. Stopping down helps to reduce CAs, however the amount stays on a rather high level. At longer focal lengths the amount of CAs is down to 1 pixel wide open, but increases with smaller apertures at 14 and 18 mm. CAs can easily be removed in post processing, though, and some of the newer Nikon DSLRs already do this in camera (if you shoot JPG).
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