Because of the increasing
popularity of digital SLR cameras, Tamron has undertaken an ambitious
plan to develop a full range of Di (Digitally Integrated) lenses. Optimized
for digital SLRs, the Di-series is just as desirable for use with 35mm
cameras, as mentioned in my review of the first two Di lenses (November,
2003). As discussed in our sidebar about the technology for digital
optimization, ultra-wide angle lenses particularly benefit from special
optical designs in order to produce the best possible results with digital
SLR cameras. That's why I was particularly interested in testing
the third Di-series lens, the SP AF17-35mm f/2.8-4 Di LD Aspherical
[IF] zoom. While shooting stock in Portland, along the Oregon coast,
in Las Vegas, and throughout the Valley of Fire State Park (Nevada),
I gave this zoom a full workout and was impressed with its many desirable
the Di technology was developed for improved performance
with digital SLRs, the 17-35mm zoom produces excellent results
with film cameras as well. Most of my 35mm slides are razor
sharp across the entire frame and exhibit remarkable sharpness,
clarity, contrast, and resolution of fine detail. (EOS-3;
HOYA polarizer; at 17mm; f/8; Fujichrome Velvia 100F film.)
Photos © 2004, Peter K. Burian, All Rights Reserved
For a wide aperture ultra-wide zoom, the 17-35mm Di is quite compact and
also lightweight thanks to the use of engineering plastics said to "excel
in dimensional stability and strength." (The lens mount is made
of metal, however.) Nicely finished in matte black with white distance
and focal length scales, the barrel features a rotary zoom mechanism,
wide, rubberized focus and zoom rings, both well damped, with enough friction
for convenient operation. Although the focus ring rotates during autofocus
operation, response is fast and fairly quiet thanks to internal focusing;
the front element does not rotate so the effect of a polarizing filter
does not shift. Because of the wide maximum aperture, the cameras'
autofocus systems remained reliable even while shooting night scenes in
When tilted upward to include most of the New York New York series of
facades in Las Vegas, the lens produced significant linear distortion.
Vertical lines seem to converge or lean inward out of plumb. Of course,
this "keystoning" is a characteristic of all short focal length
lenses and occurs whenever certain subject elements (such as the base
of the buildings) are closer to the lens than others. For images with
"normal" perspective, simply position the camera back so it's
perfectly parallel with the subject. Granted, you may find a bit of barrel
distortion (bowing outward of lines near the edge of the frame) in full
frame digital images or 35mm slides and negatives made in the 17-20mm
range. This is common with most ultra-wide angle lenses but in my estimation,
it's problematic only in formal architectural photography.
17-35mm Di zoom focused very quickly, particularly when
used with a camera with an advanced autofocus system. That
combination made the lens ideal for capturing a nearby action
subject or a fleeting moment without the frustration produced
by some equipment that often hunts for focus. (EOS-1Ds;
at 35mm; f/4.5 at 1/1000 sec; ISO 50; HOYA polarizer; image
As noted in our sidebar, the 17-35mm Di zoom incorporates both aspherical
and low dispersion glass for optimum image quality at all focal lengths.
This high tech optical formula pays dividends in image quality as I confirmed
with a 35mm EOS-3 and a digital EOS 10D and EOS-1Ds. At all focal lengths,
the lens produced images and color slides with very high contrast, sharpness,
color fidelity, clarity, and remarkable resolution of intricate detail
at every aperture from f/2.8 to f/11. This consistency indicates a particularly
effective optical design. Because there was no need to stop down to optimize
image quality, I felt confident shooting at f/2.8 or f/4 on dark, overcast
Oregon days, allowing me to use an lSO 100 setting with the EOS 10D for
optimal image quality.
Particularly in the 17-30mm range of focal lengths, and especially at
f/8, image quality is superlative with edge sharpness matching central
sharpness. Flare was very well controlled, a real benefit on sunny days
in the Valley of Fire State Park, even in extreme sidelighting. In all
of my images, brightness is consistent across the entire frame, at all
focal lengths, by one stop down from the maximum aperture. My best digital
images made for exhibition quality 11x17" ink jet prints and my
Velvia 100F slides are also technically exceptional.
17-35mm zoom rendered this highly reflective subject--photographed
with a digital SLR camera with a highly reflective sensor--without
any evidence of flare, thanks to the extensive use of new
multilayered coatings. (EOS-1Ds; ISO 50; f/8; at 19mm; HOYA
I considered this 17-35mm Di lens to be an ideal ultra-wide zoom with
the EOS-3 and the EOS-1Ds with its full frame CMOS sensor. At the shortest
focal lengths, it allowed me to include a vast panoramic scene in a single
image and in close focusing it produced more powerful wide angle effects
than my 20-35mm zoom. The expanded spatial perspective at 17mm makes nearby
rocks seem to loom while distant subjects seem to recede for a greater
sense of depth in a two-dimensional photo. When mounted on the EOS 10D,
with a smaller sensor, the effective focal lengths were 27.2-56mm in terms
of the effective angle of view, less useful for dramatic effects. Still,
this lens would be a suitable "normal" zoom for any digital
SLR with an APS-size sensor, more useful than a 28-80mm zoom that cannot
produce true wide angle images with such cameras.
used with a 35mm SLR camera, the 17-35mm Di zoom produces
images with a super wide angle of view (Photo A) at the
shortest focal length. The angle of view is narrower (Photo
B) when used with a digital SLR camera with a small sensor
but the images retain a wide angle.
(EOS-3; f/11; HOYA polarizer; Fujichrome Velvia 100F film;
vignetting caused by polarization of the sky; 35mm slides
used for illustration of effective angle of view.)
This "Digitally Integrated"
zoom allowed me to make many images of professional caliber. But did it
produce better results than conventional lenses when used with the EOS
10D? As in my review of the previous two Tamron Di lenses, I cannot provide
a definitive conclusion. Frankly, that determination could only be made
with a fully equipped optical lab. It would require scientific comparison
testing with several similar ultra-wide angle zooms, with and without
the Di technology.
Nonetheless, I can offer the following assessments of the Tamron SP AF17-35mm
f/2.8-4 Di LD Aspherical [IF] zoom. It's superior in most respects
to the older SP AF20-40mm f/2.7-3.5 Aspherical [IF] zoom that I used frequently
for stock photography for several years. In fact, this new Di lens is
probably the best ultra-wide zoom that Tamron has ever produced. Whether
you own a 35mm or digital SLR camera, check out this lens if you're
a serious photographer who wants the latest technology and appreciates
the creative and problem-solving benefits of a 17-35mm zoom.
For more information, visit Tamron's website at: www.tamron.com.
Peter K. Burian, a free-lancer
stock photographer and long-time "Shutterbug" and eDigitalPHOTO" contributor,
is the author of a new book, "Mastering Digital Photography and
Imaging" (Sybex, March 2004). Covering all aspects of the topic--the
technology, equipment, and techniques--this book provides 300 pages
of practical advice for photo enthusiasts.
at wide apertures the "Digitally Integrated"
17-35mm Di zoom produces images with even brightness across
the frame, high resolution of fine detail, and great sharpness.
There's no need to stop down to small apertures to
optimize image quality as with some conventional lenses.
(EOS 10D; at 17mm setting for 27.5mm equivalent focal length;
at f/4; ISO 100.)
The Value Of Digital
The vast majority of autofocus lenses were designed to produce optimum
results when used with 35mm SLR cameras. Although they can also be used
with digital SLR bodies, some lenses do not produce the same level of
quality on the new, high tech cameras. Particularly at wide apertures,
internal reflections can cause more serious flare, "ghosting"
(reflections in the shape of the lens diaphragm), low contrast, as well
as light falloff, resulting in darkening at the edges of the frame.
Most of these problems occur because CMOS and CCD sensors are highly reflective.
When light reflects from the sensor (or from the protective glass cover),
it bounces to the rear element of the lens creating flare that can degrade
image contrast and apparent sharpness. In most lenses for 35mm systems,
the rear element is not coated with multiple layers of anti-reflective
compounds because the matte film surface produces only diffused reflections.
The stronger reflections in a digital camera can degrade image quality
to a greater extent, calling for additional anti-reflection countermeasures.
In the Di lenses, a new type of multilayered coating is applied to more
lens elements (including the rear element) to minimize internal reflections
for images with snappier contrast.
There's another characteristic of CCD and CMOS chips that must be
considered when designing a digitally optimized lens: The sensors produce
the best results with light that strikes all pixels at a 90Þ angle.
With many conventional lenses, particularly ultra wides, the light reflected
from the subject strikes the image plane at an increasingly oblique angle
as you move toward the edges of the frame. This can cause a darkening
at the corners of a digital image and occasionally, lower resolution,
especially noticeable in wide angle shots made at wide apertures. (At
f/8 and smaller apertures, neither problem is significant.) While some
digital camera manufacturers have used light altering systems to help
minimize the effect, not all do, and some do more successfully than others.
When designing the 17-35mm Di zoom, the engineers specified three aspherical
elements to correct the angle of light plus other measures for increasing
corner "luminosity" or brightness. These steps minimize "peripheral
light falloff" for even brightness across the frame even at wide
Tamron hesitates to reveal full details about proprietary technology,
but the new 17-35mm Di zoom also benefits from a low dispersion glass
element plus "highly balanced optical instrumentation to achieve
high contrast in the low frequency range for higher resolution."
The special types of glass also correct optical aberrations and distortion
while optimizing color rendition, enhancing lens performance with any
type of camera. Consequently, this ultra-wide angle Di zoom would be a
suitable choice for serious photographers regardless of the type of equipment
that they use.
Construction: 14 elements in 11 groups
Angle Of View (In 35mm Or Full Frame Format): 104Þ-63Þ
Maximum Aperture: f/2.8-4
Minimum Focus: 11.8" over entire zoom range
Maximum Magnification: 0.19x
Filter Size: 77mm
Weight: 14.4 oz
Available AF Mounts: Canon, Minolta, Nikon-D, Pentax
Street Price: $479