Nikkor AF 50mm f/1.8 D - Review / Test Report - Analysis
Lens Reviews -
Nikon / Nikkor (APS-C)
Page 2 of 3
As expected for a fix-focal lens the level of (barrel) distortions is very low (0.26%)
and nothing to worry about.
The chart above has a real-world size of about 120x80cm. Possibly things may get a little
worse with extreme close-ups.
Thanks to the sweet spot behavior on the D200 vignetting is very well controlled.
Wide-open vignetting is a little stronger at ~0.66EV which may be visible in
very critical scenes. From f/2.8 and up the problem is negligible.
Update 04/11/2006 - tested new sample which performed better at the borders.
Standard lenses are stellar performer when used at medium aperture settings
and the Nikkor AF 50mm f/1.8 D is no exception here. At f/4-f/8 the lens
is surely as good as it gets on the D200 with an excellent center
and a very-good border performance. Nonetheless it is also fairly typical
for ultra-large aperture lenses that things aren't quite as rosy at wide-open aperture but
the center is already excellent here whereas the borders are a bit soft
(combined with rather low contrast). From f/2.8
and up the distribution of the MTF50 curve suggests that the center performance
exceeds the quality of the D200. The borders improve continuously with good
figures at f/2.8 and very-good results at f/4.
The lens showed slight residual spherical aberrations (focus shift when stopping down).
Below is a simplified summary of the formal findings. The chart shows in line widths
per picture height (LW/PH) which can be taken as a measure for sharpness.
The chart is limited to the visually relevant LW/PH range of [750, 2250].
If you want to know more about the MTF50 figures you may check out the corresponding
Chromatic Aberrations (CAs)
Chromatic aberrations (color shadows at harsh contrast transitions) are relatively
pronounced for a fix-focal with an average pixel width of 1.2px at the image borders.
Nonetheless it´s not a major problem. Stopping down improves the issue to moderate