. Canon
EF 17-40 4L USM An "L" of a
Lens Peter
Kun Frary
Agashi at Aloha
Tower Market Place • EOS 10D, EF 17-40 4L
USM, 420EX Speedlite, ISO 800, Daylight WB, Av Mode
(F4, 1/30), -2/3 FEC. External flash coverage at 17
mm with 1.6x EOS bodies is no problem due to the
cropping factor (i.e., 17 mm behaves like 27
mm). Construction
& Feel The optical design
and antireflection coatings of today's zooms have
evolved to the point the best examples rival prime
lenses. Unfortunately, most consumer zooms are
cheap plastic affairs with silk-screened symbols
and coarse zoom and focus action. Canon's EF 17-40
4L USM bucks this trend and combines modern optical
design and AF with the durable construction and
silky zoom and focus action of yesteryear. At $650,
it's more affordable than the EF 16-35 2.8L USM
($1300), but offers similar build and optical
quality. EF 17-40
4L USM • Constant
aperture, internal zoom and focus, weather seals and
compact design leave little more to be desired in a wide
zoom. The hybrid metal
and plastic construction (polycarbonate barrel) and
quality components make the EF 17-40 4L USM tough
as nails, but a lightweight 475 g (16.8 oz). Plus,
the moisture and dust seals, including a rubber
O-ring on the lens mount, make it a great choice
for jungle and beach shooters. Canon recommends the
use of an UV filter for total weather sealing. This
zoom feels solid and well made. The EF 17-40 4L USM
is a classic two-touch design: focus ring near the
end of the barrel and zoom ring near the mount.
Once you get used to this design, handling is
nimble and decisive. Both zoom and focus mechanisms
are internal so there is no extension of nested barrels.
Moreover, internal mechanisms are less prone to sucking
in
dust than front extension designs. Unlike most AF
lenses, the manual focus ring is large, ribbed,
rubberized and nearly as smooth turning as the
manual lenses of yesteryear. Plus, the flat black
finish is elegant and the overall appearance
similar to the EF 16-35 2.8 USM. Venetian Ceiling
Detail • EOS
10D, EF 17-40 4L USM, 430EX Speedlite, ISO 100, Tv
Mode (29mm, F4, 1/60). Auto
Focus This lens sports a
ring-type USM (Ultrasonic Motor) that drives an
internal lens group and, thus, AF rips. The front
element does not rotate nor does the barrel expand
or contract during focus and zoom operations. The
motor of the EF 17-40 4L USM is silent during AF.
It has FTM, allowing you to manually focus without
switching out of AF mode. If you prefocus manually,
the distance window in meters and feet is extremely
useful. The zoom's AF
worked flawlessly on my EOS
5D, 3, Elan
7E, 10D, Elan, IX, A2
and 20D bodies. That is, AF is fast, accurate and decisive.
Moreover, the maximum aperture of F4 is sufficient
to fully enable the center AF cross sensor on all
six EOS bodies. Unfortunately, this lens isn't well
suited for older pro EOS cameras, e.g., EOS 1 or
1N, as the maximum aperture of F4 is too slow to
fully enable their cross AF sensors. The filter size is
77 mm, making filters expensive and difficult to
share with Canon consumer lenses. The EF 70-200 2.8L IS
USM and EF 24-105 4L IS USM are among the few Canon lenses
to share this filter size and sport a complementary zoom
range,
making for an excellent albeit expensive combo. The
clearance from the edge of the front element to the
filter threads is huge and, subsequently, normal
thickness filters such as my Hoya Super HMC UV do
not vignette on full frame (36 x 24 mm). Drummer
Boy • Moana Surf Rider Hotel, Honolulu, Hawaii
• EOS
10D, EF 17-40 4L USM. As expected, the EF
17-40 4L USM is very sharp and contrasty, a clear
level above my EF 24-85 3.5-4.5 USM (a decent
lens). The constant F4 aperture is a big plus for
hand meter users and those that prefer manual or
aperture priority exposure modes. Another advantage
of this lens over consumer zooms is it exhibits
little image degradation at large apertures or at
the long end. In other words, it's sharp wide open
and across the zoom range. Stopped down to F8 or
F11, images from this lens and the EF 24-85 3.5-4.5
USM are nearly indistinguishable. Nevertheless, top
image quality wide open is essential if you
frequently hand hold your camera. The contrast and
snap of this lens is apparent even through the
viewfinder. After all, there's some exotic
glass in there, e.g., 1 UD and 2 aspherical
elements. The short end, like most wide
zooms, shows considerable barrel distortion. The long end has
a
small amount of pincushion distortion. For most
use, distortion isn't a problem. However,
architectural and product photographers should stick
with primes. Flare is extremely
well controlled for a zoom. With full frame
coverage (e.g., 35 mm film), some flare and
ghosting may occur with bright sunsets. Smaller
formats, e.g., APS film and APS-C digital, exhibit virtually
no flare or ghosting. You should use the huge lens
shade (EW-83E) to protect the lens and help keep
flare in check. Casino at
Fremont Street • EOS 10D, EF 17-40 4L USM:
ISO 100, 22mm, F4@1/15 Cons There aren't many
cons about this lens, so I'll have to nitpick. The
included hood is really bulky
and doesn't afford much protection.
It scares people and blocks the popup flash at all focal lengths.
With
the hood
removed,
the
EOS 10D's popup is fine from 24-40 but is blocked
at wider settings. Surprisingly, it does
not block the 20D popup at any focal length as long as you
leave the hood off. In
terms of popup blockage, every camera model is different so
test before an important shoot.
Of course, it's fine with an
external flash, although some flash units may not cover
the widest focal
lengths on full frame cameras. For example, 420EX
coverage only extends to 24mm with full frame EOS
bodies, e.g., EOS 3 or 1Ds. In contrast, the 420EX
Speedlite is fine at all focal lengths with 1.6x
bodies such as the EOS 10D or 20D. This is an
incredible ultra wide zoom on my EOS 3 and 5D but a
bit of a yawn on cropped frame bodies
such as the EOS
10D or 20D. Why? The cropping factor essentially makes
it into a
boring 27-64
zoom.
I'd
like more reach for a walk around zoom.
However, a 17-40
zoom is a thrill through the big, bright
viewfinder of an EOS 3 or 5D. I just have to be careful
not to include my feet in the
photographs! Final
Words If you shoot
architecture or mainly use the short end of a wide
zoom, buy a wide prime. Primes are smaller and have
much less distorion. If you like to hand hold in
murky light, buy a wide and fast prime. However, if
you need the versatility of a wide zoom, this is
among the best. The EF 17-40 4L USM has similar
build and optical quality as the famous EF 16-35
2.8L USM, but at nearly half the price, weight and
shy a F stop. Most pros will buy the EF 16-35 2.8L
USM as the extra stop may mean the difference
between getting a paycheck or not. For
discriminating hikers, travelers and serious amateurs this
zoom deliverers quality without breaking their
shoulder (and bank) and can take the knocks they
dish out. Highly recommended. Roundtop Drive
View • EOS 10D, EF 17-40 4L USM Focal Length: 17-40
mm Aperture: F4 to
22 Lens Construction:
12 elements in 9 groups with 1 UD and 2 aspherical
elements Min. Focusing
Distance: .28 m/.92 ft Diameter &
Length: 83.5 x 96.8 mm/3.3 x 3.8 inches Weight: 475 g/16.8
oz Included
Accessories: EW-83E Lens Hood and Storage
Bag Cost:
$650 1/17/2004
• Updated 1/12/2007 .
If you're
particular about image quality, buy the best lenses
you can afford. After all, the caliber of your
images will be determined by the quality of the
lens and your technique, not the camera. Quality
EF lenses are an investment for the future as they'll
work on all EOS SLRs, film or digital.
The wide
zoom--16-35, 17-35, 17-40, 20-35, et al.--has been
a mainstay of pros, especially photo journalists,
since the early 1990s. These focal lengths are
perfect for sweeping views and shooting in tight
quarters, and are easily hand holdable. However,
wide zooms are a recent design innovation and have
been prohibitively expensive for the best examples.
Prior to the 1990s you needed a set of primes for
similar coverage. Back in the day, my Nikkor 28-50
3.5 AIS was an expensive "wide" zoom (it still
holds its own optically with modern zooms). Quality
17, 18 and 20 mm primes were and still are
expensive.
Optical
Performance
Specs
