Review Nikon AF-S 28mm f/1.8 G @ DX

17 July 2014

Is the Nikon 28mm 1.8 the perfect 35mm for Nikon DX?

Lenses with a fixed focal point are often available in two varieties: a light and inexpensive version for the serious amateur, and a heavier, professional version that is typically brighter and in any case much more expensive. The Nikon 28 mm f/1.8 falls in terms of price and execution into the first category, and yet has the brightness of the professional category. On an APS-C/DX camera, the effective focal distance is not 35 mm, but 42 mm. This type of lens is suitable for landscapes, for “all around” documentary use, as well as for portraits, if you leave some space around the model free.

Nikon AF-S 28mm f/1.8 G & D7100 @ f/8, 1/125 sec, 100 ISO
Why a full-frame lens on an APS-C body?
Why would you put a full-frame lens (FX in Nikon terminology) on an APS-C (DX) body? With such a lens, you then use, after all, only the inner half of the image circle. You still have to deal with the weight – and not to forget the price – of a full-frame lens. Even so, there are three reasons to consider this FX lens for a DX body as well: FX lenses are, as a rule, superior in terms of image quality. After all, they are intended for sensors with a whole lot of pixels. Because with a DX body you only use the middle of the image circle, flaws such as distortion will be reduced, and vignetting and edge blur will even be largely eliminated. In the second place, you have, if you later switch from DX, on FX format, the certainty that you can keep using your “old” lenses. In addition, there are not many DX lenses with brightness like this f/1.8.
Build and auto focus
The lens has a plastic housing; this ensures low weight (ca. 300 g) and reduces costs. The high brightness has advantages in low light but is primarily intended for the creation of nicely blurred backgrounds. You can ‘free’ your subject from the background. The use of plastic makes the lens – at least in theory – more prone to incidental front focus/back focus (as a consequence of thermal expansion) and somewhat more fragile that with an entirely metal housing. There is a broad rubber focus ring and a window that shows the distance set. With a switch, you select MF or M/A, in which case you focus automatically but can still turn ‘through the focal point’ by hand. An advantage of a bright lens is that the automatic focusing happens faster and, as a rule, more precisely. When focusing by hand, a limited amount of ‘play’ was noticeable. This is a disadvantage when you want to photograph while zoomed in via Live View on your LCD screen (or connected laptop or tablet).	{insertgrid ID = 289}
Vignetting Nikon 28mm f/1.8G
There is some vignetting in the corners at full aperture, about three-quarters of a stop. This is barely visible in practice shots, as shown in this picture of a clear sky. Move your mouse over the picture for the Imatest results.
Distortion
In the JPEG mode, the distortion will be immediately corrected by the camera. In RAW, there is some (-0.8%; 30% lower than on an FX camera) distortion visible. Distortion is simple to correct with software, at the expense of a little bit of corner sharpness.
Flare
Just as in our review with the Nikon 28mm 1.8G on a Nikon D800E, we encountered no flare in the practice shots without using a sun cap, not even when we photographed directly against the sun.
Sharpness
For a lens in the amateur or the “prosumer” category (the serious amateur but not the fully pro photographer), this lens performs well. The center sharpness (measured on the D7100) is outstanding starting with aperture f/2.8. The corner sharpness lags a bit. You get the best results at f/5.6. The lens is in fact better than the body, because the same lens on the D800E gives a considerably higher resolution.
Nikon AF-S 28mm f/1.8 G & D7100 @ f/5.6, 1/640 sec, 100 ISO You see no distortion here, but skew because the photographer was not standing directly in front of the subject and held the camera at an angle.
Chromatic aberration
We did not capture any chromatic aberration. From the cross-section shown here, you see that the lens is built from no fewer than 11 lens elements, of which some are placed together. Such groups, made up of two different glass types, serve to reduce or eliminate chromatic aberration.
Bokeh Nikon 28mm f/1.8G
The bokeh (the quality of the blur) can be called fine with this lens. That comes from, among other things, the 7 rounded aperture lamellae. This is also an advantage of FX lenses above DX: they typically have more aperture lamellae because there’s more space in the lens housing. From the just-visible onion-ring pattern, it can be seen that there are 2 aspherical lenses applied in the design of the Nikon 28 mm 1.8G.
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Conclusion Nikon AF-S 28mm f/1.8 G test with Nikon D7100
	See our list of tested lenses or the lenses with a Nikon mount tested by us to compare the performance of this lens to other lenses.
WYSIWYG score: This table shows the performance of this lens if you save the files in the camera as jpg, where you have applied all available in-camera lens corrections. This score gives you for this lens/test camera combination: “What you see is what you get”. testcamera: Nikon D7100	{insertgrid ID = 308}
Pure RAW score: This table shows the performance of this lens if the file is saved in the camera as a RAW file. This score approaches the intrinsic quality of the combination of lens and test camera.	{insertgrid ID = 309}
Pros	Cons
High image quality High brightness No/very little flare Fine bokeh	Larger, heavier and more expensive than a DX lens
This Nikon 28 mm f/1.8 is an attractive lens with very good resolution and a reasonable price/quality ratio. Of the 22 lenses that we have reviewed with a focal point between 23 mm and 30 mm, the Nikon 28 mm f/1.8G lands in the top 5, regardless of whether you’re looking at a jpg file (incl. in-camera corrections and standard sharpening) or a RAW file (without sharpening or corrections). Is this then the ideal documentary lens for a Nikon photographer with a DX camera? There are after all multiple, although less bright, zoom lenses that offer equally good image quality at this focal length. And the Sigma 18-35 mm f/1.8 not only has the same brightness, but is at least as good qualitatively. On the other hand, the Sigma 18-35 mm cannot be used on a (future) camera with an FX sensor. You also mustn’t underestimage the pleasure that many photographers experience with a fixed focal length. As far as that’s concerned, the Nikon 28 mm f/1.8G is clearly the ideal 35 mm lens for a DX camera.