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Through the generosity of Don Ferrario and Dewey Neild, who lent me their
17-35mm f2.8 and 18-35mm f3.5-4.5 Nikkor zooms, I was able to compared them
with each other, and with several
good Nikkor non-zooms of similar focal-lengths. All the lenses at the zoom
short ends appeared consistent in focal length for their rated FLs (as in, the
15 was considerably wider than the 17-35, which was a bit wider than the
18-35, which was somewhat wider than the 20mm - and the lens angle of view
increased with close-focus with the zooms, contrary to what happens with most
non-zooms). All the lenses compared showed good
alignment, though the focus of the 17-35mm shifted with the focal length
selected. The 17-35mm is notably heavy and large; the 18-35 is much lighter
and appears much smaller, though it takes the same 77mm filter size, and is
only about 3/4" shorter. Both zooms handled well, with smooth-operating
rings. The front does not rotate on either with zooming or focusing (with
about 1
foot minimum focus for both). With both lenses, for a given aperture the
contrast in the center improves and the corners decline as the lenses are
zoomed toward the wide end. With the 17-35mm f2.8, Nikon appears to have
built a lens that about equals the performance of the best Nikkor AF non-zoom lenses
in its range, with the exception of the 28mm FL in this sample at the widest
stops (though the best of the MF 28mm and 35mm Nikkor AIS lenses are still
better than the same-FL AF lenses currently offered). By f5.6, the 17-35mm is
quite good throughout, and the performance changes little with focus distance.
With the 18-35mm
f3.5-4.5, Nikon offers a far less expensive lens that also performs well, but
not as well as the 17-35mm, particularly at the edges and corners wider than
f11, and as the FL approaches 35mm at mid-close focus distances (though the
predominant slight barrel distortion of the 18-35mm is preferable to the
predominant slight pincushion distortion of the 17-35mm). If using f11 is
practical for most of what the lens will be used for, the 18-35mm performs
very well at that stop throughout (and at wider stops at middle FLs), and the
savings in weight and price are not small compared with the 17-35mm (and since
a smaller part of the image area is used by digital cameras like the Nikon D1
and D1X, this lens can serve well if used on those even at wider stops); if
wider stops are needed, the 17-35mm is good throughout by f5.6, and even at
wider stops if used with an understanding of its limitations (especially if
the corners and far edges are not included in the image); at f2.8 and f4, a few non-zoom MF
Nikkor 28mm and 35mm lenses perform better than the 17-35mm zoom, if the best image quality is needed at those stops.
Notes:
- The
following Nikkor lenses were compared: 15mm f5.6
AI, 20mm f2.8
AIS, 24mm f2.8
AF,
35mm f2
AF, 17-35mm f2.8
AF, and 18-35mm f3.5-4.5
AF.
- The distortion types mentioned are none, barrel, pincushion, and the
hybrid wavy-line, in
amounts of none, very slight, and slight.
- The lenses were checked at the widest available whole stop (with the
exception of the 35mm
f2, for comparison consistency), and also
at f5.6 and f11.
- Fuji 100-speed negative film was used for testing, with a 10X
magnifier used to examine the
full-frame 35mm negatives.
- The numbers given are ratings for sharpness for the major part of the
frame, and in
parentheses, the ratings for the far corner sharpness
(the small area that would almost
slip under a slide mount or negative carrier).
- Fractional ratings are used to differentiate very close, but just
detectably different, images.
- The ratings are as follows (the first six would be acceptable only in
the far corners of an
otherwise good image):
1
soft minus (very little detail showing)
2 soft (little detail showing)
3 soft plus (some detail showing)
4 OK minus (barely acceptable far-corner image)
5 OK (acceptable quality for very small parts of the image)
6 OK plus (acceptable for small images)
7 good minus (at the lower edge of acceptability for most of the
image area)
8 good (average-looking, noticeably softer than the best)
9 good plus (good-average image)
10 very good minus (good fine detail, but without a "crisp" look)
11 very good (very good fine detail and good-looking image)
12 very good plus (very sharp-looking, but without the "snap" of
the best images)
13 excellent minus (clean image edges, excellent fine detail)
14 excellent (very crisp and clean image, "snappy"-looking)
15 excellent plus (VERY crisp and "wiry" image)
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