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Nikkor AF-S DX 35mm f/1.8 G - Review / Test Report - Analysis |
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Lens Reviews -
Nikon / Nikkor (APS-C)
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Page 2 of 3
Distortion
The lens shows moderate barrel distortion at around 1.7%, which is a bit more than one would expect from a prime lens in this focal range.
The chart above has a real-world size of about 120x80cm.
Vignetting
Dedicated DX lenses usually suffer from higher vignetting (compared to FX glass on the same camera) and one would especially expect this behaviour from a fast lens. Consequently, the AF-S DX 35 shows moderate vignetting wide open, which is reduced to a not field-relevant level by f/2.8 already.
MTF (resolution)
The lens deliveres excellent resolution figures in the center thoughout the whole tested aperture range, except for f/11 where diffraction reduces the maximum sharpness. The borders follow closely behind with very good values wide open and (just) excellent resolution at f/2.8 and f/4.
The extreme borders are about one school mark softer wide open and reach only good values, however stopping down helps to increase the resolution here. The global performance peak is reached by f/4, but the lens performs on a similarly high level at f/2.8 already.
The lens showed a slight amount of focus shift when stopping down (residual spherical aberration).
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)
Chromatic aberrations (color shadows at harsh contrast transitions) are moderate wide open, but rather high for the rest of the aperture range. This is a somewhat disappointing behaviour, however lateral CAs (unlike LoCAs, see below) can easily corrected in post processing and most newer Nikon DSLRs already do this on their own (as well as most of the current RAW converters).
Bokeh
Unfortunately at wide open aperture the AF-S 35 shows a rather high amount of outlining resulting in a slightly nervous bokeh. From f/2.8 onwards these outlines disappear and the bokeh smoothens considerably, however highlights in the background remain troubled by bokeh fringing (see next section). In addition, despite rounded aperture blades, from f/5.6 onwards highlights in the background start to lose their circular shape.
Bokeh Fringing
Bokeh fringing is a general problem in this lens class. As you can notice below the halos have different colors - magenta (red + blue) in front of the focus point and green beyond. Typical for most fast primes the AF-S 35 shows a considerable amount of bokeh fringing at large aperture settings. Stopping down helps to reduce the amount of LoCAs significantly.
In addition, these shots also show the focus shift when stopping down, which was mentioned in the MTF section.
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Move the mouse cursor over the f-stop marks below to observe the respective bokeh fringing
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| f/1.8 |
f/2.8 |
f/4.0 |
f/5.6 |
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