Nikkor AF 180mm f/2.8 IF-ED - Review / Test Report - Analysis
Lens Reviews -
Nikon / Nikkor (APS-C)
Wednesday, 26 December 2007 04:19
Page 2 of 3
The AF 180mm f/2.8 IF-ED produces a very low degree of pincushion distortion (0.3%) which is
not relevant under field conditions.
The chart above has a real-world size of about 120x80cm.
Thanks to the sweet spot behavior on the D200 vignetting is very well controlled
even at max. aperture (0.36EV). You can easily go ahead shooting at f/2.8
without worrying about the issue.
The F 180mm f/2.8 IF-ED was able to show very good to excellent resolution
figures in the lab. Even better there's only a negligible difference between
center and edge performance. The peak quality is reached at f/5.6 but
it's only marginally worse at large aperture settings.
Beyond resolution the lens also convinced by providing exceptional contrast
and a very good bokeh (out-of-focus blur although there's also some bohek fringing.
Both criterias are not measurable via the Imatest test procedure but the quality
is obvious in real life images.
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
Chromatic Aberrations (CAs)
Lateral Chromatic aberrations (color shadows at harsh contrast transitions) are very low and hardly
an issue under field conditions. You may spot a little purple fringing here and there though
(see e.g. the waterdrops on the swan sample below).
Some readers were surprised about this finding because the current consensus suggested otherwise.
Possibly the tested sample was simply very good in this respect - below is one of the border sample portions
(@ f/4) where CAs are measured. As you can visually confirm the tested sample has no real issue here.
Upper left corner @ f/4
Lower right corner @ f/4