AF Nikkor 28mm f/2.8D lens review
Released in 1994, the AF Nikkor 28mm f/2.8D is a full–frame, fixed–focal–length lens that can be used on both FX and DX format cameras. Its angle of view is that of a perfect general–purpose wide–angle lens when the optic is mounted on an FX camera; on a DX camera its angle of view is closer to that of "standard" lenses. The lens has six elements in six groups and dimensions of 64mm by 44.5mm; it focuses down to 25cm, weighs only 205g and takes 52mm filters. The lens does not have the CRC (Close Range Correction) system—AF Nikkor 28mm f/1.4D does. If necessary, you can find simple explanations of the terms below here. This, this and this photograph was taken with it.
The lens was tested on a 12MP Nikon D700 camera. FX format cameras of higher resolution will put a further emphasis on some of the performance deficiencies reported in the review. At the same time, light fall–off, distortion and corner sharpness will be less problematic when the lens is used on a DX format camera.
Handling and autofocus
The lens is very light and compact and balances beautifully on all Nikon camera bodies I have tried it on. When mounted on bigger cameras such as the Nikon D700, the lens is completely unobtrusive and does not make your camera nose dive when you carry it on your shoulder, which makes it a great walk–around companion if 28mm is your preferred focal length.
Lens mount is metal; lens barrel, on the other hand, is made of high–quality plastics that, thankfully, do not give the lens a "plasticy" feel. Indeed, the lens has a certain heft to it and, due to this, leaves the impression of a solidly built optic. Filter thread is made of plastic, too; it does not rotate during focusing, which makes using a polarizing filter easy.
Autofocus speed will largely depend on the camera body used. On the Nikon D700, autofocus is very fast and accurate, albeit somewhat audible. The lens uses camera body's AF motor for focusing and thus on Nikon's lesser DX format cameras that do not have a lens drive (D40, D40x, D60, D3000 and D5000) can be used in manual focus only.
Centre: the lens is softish at f/2.8 but centre sharpness improves at f/4; to all intents and purposes it is equally sharp from f/4 through to f/11. Diffraction becomes visible at f/16 and further takes its toll at f/22; I would avoid using the smallest aperture if centre sharpness is of crucial importance.
Corners are soft wide–open; corner sharpness then gradually improves as the lens is being stopped down until it peaks at f/11; as expected, diffraction becomes evident at f/16 and further worsens sharpness at f/22.
Farthest corners are very soft from f/2.8 to f/5.6, become acceptably sharp at f/8 and slightly improve further at f/11; here, however, they are still not as sharp as the centre. Starting from f/16 sharpness slides downhill again due to diffraction.
As the test shot below shows, the lens shows very visible vignetting at f/2.8. In fact, it is so strong at this aperture that it is more akin to overall underexposure than to vignetting; furthermore, it is nearly impossible to completely remove in post–processing.
Vignetting is much more reasonable at f/4 and might actually come in handy if one wants to emphasise the main subject. The aberration will not be noticeable in most situations at f/5.6 and is virtually gone by f/8.
The lens produces modest barrel distortion that is not bad enough to be noticeable in most images yet just over the brink for the lens to be suitable for architectural applications. Distortion is more pronounced at closer distances and, to make things worse, has a complex ("mustache") signature, due to which the aberration is very difficult to completely remove in post–processing.
Chromatic aberration can sometimes be seen around (very) contrasty edges; however, even when it is visible its degree is very low and the aberration can be removed in post processing.
The lens has a relatively simple design as well as a fairly small front element and, partially due to this, flare is very well controlled; even shooting directly into the sun does not massively degrade contrast. It is possible to induce ghosting by having very bright sources of light in an image but ghosting is normally minimal in both amount and size.
AF Nikkor 28mm f/2.8D is a wide–angle lens and bokeh usually should not be of a major concern—for one thing, I seem to have very, very few pictures with out–of–focus background taken with this lens. Nevertheless, if you are interested, bokeh is somewhat harsh at f/2.8, fairly neutral at f/4 and becomes silkier at smaller apertures.
The lens does not perform well wide open at all; its performance improves at f/4 but then again f/4 is not an exactly fast aperture. The lens' only saving grace is that it performs very well at f/11. If you are looking for a small, light, inexpensive general–purpose wide–angle lens and expect to use it stopped down most of the time, then the AF Nikkor 28mm f/2.8D is a good choice. Otherwise, I would look elsewhere.