Canon announce the EF-S 17-85mm f/4-5.6 IS USM and EF-S 10-22mm f/3.5-4.5 USM
wide-angle EF-S zoom lenses. Targeted at advanced digital photographers, both
lenses are designed to work exclusively with Canons EOS 20D and EOS 300D
digital SLR cameras. The focal length ranges of the new lenses are equivalent
to 27-136mm and 16-35mm respectively in 35mm film format a spread carefully
chosen by Canon to reflect the needs of its rapidly growing base of advanced
Both lenses feature Canons ring-type Ultra Sonic Motors (USM) for fast,
near-silent auto focus, and a range of features designed to deliver a level
of image quality approaching that of Canons revered L-Series professional
Ideal for travel, mid-range nature/wildlife and general photography, the EF-S
17-85mm f/4-5.6 IS USM is a high quality, lightweight, all-purpose standard
zoom lens. This 5x zoom lens offers the widest range of any lens in its class,
and features Canons latest optical Image Stabilizer technology, providing
up to 3-stop compensation for image blur caused by camera shake and slow shutter
speeds. With superb quality suited to semi-professional use, the lens has a
17 element, 12 group construction, including one double-sided aspherical element
for crisp, high contrast corner-to-corner detail.
The EF-S 10-22mm f/3.5-4.5 USM is the markets lightest and smallest 16-35mm
(35mm equivalent) zoom lens available; ideal for landscape or indoor photography,
or for photographers wishing to experiment with pan-focus and dramatic perspective
effects. It also boasts a remarkably close focusing distance of just 24 cm.
With similar high build quality to the EF-S 17-85mm f/4-5.6 IS USM, the EF-S
10-22mm f/3.5-4.5 USM includes a Super UD (ultra-dispersion) glass lens and
two aspherical elements in its 13 element, 10 group construction. The non-rotating
front element makes it ideal for use with filters such as polarizing and graduated,
both of which are popular for the type of landscape photography for which the
lens is suited.
Both lenses feature Canons EF-S lens mount, matched to the EOS 20D and
EOS 300D digital SLRs. The APS-C sized sensor of these cameras results in an
effective multiplication factor of 1.6x the indicated focal length. While this
creates an obvious advantage for telephoto lenses, it is less beneficial when
meeting wide-angle requirements. To meet the needs of new digital photographers,
Canon developed the wide-angle EF-S lens mount. The EOS 20D and EOS 300D are
both completely compatible with all existing EF lenses, while EF-S lenses only
fit these two cameras. Optimized for Digital SLRs with APS-C size sensors, the
EF-S mount enables economic wide-angle solutions often required by advanced
The S in the EF S nomenclature stands for the term short
back focus. This describes the system that allows the rear lens element
of EF-S lenses to be positioned closer than normal to the image sensor of APS-C
sensor cameras. A white lens mount index differentiates the lenses from other
EF lenses, which retain their traditional red marking. A rear rubber ring prevents
any damage in the event that an inadvertent attempt is made to mount the lenses
on non-compatible cameras.
The ring-type USM motors found in both lenses employ ultra-sonic frequency vibrations
to drive focussing with unrivalled speed. Canons ring-type USM holds the
lens with precision and accuracy, the instant it arrives at the correct focus
point and without overshoot. To further improve accuracy and speed, the drive
patterns of both lenses are tailored to specifically match that of the EOS 20D
and EOS 300D. Both lenses also feature full-time manual focus override without
risk of motor damage.
Appealing background blur
The lenses both incorporate an EMD (electromagnetic diaphragm), which employs
an almost perfectly circular barrel aperture. This helps create an attractive,
even background blur when the photographer minimises depth of field to isolate
Perfect for digital photography
By optimising lens coatings, Canons engineers have been effective in suppressing
flare and ghosting, which are more prone to occur with digital cameras due to
reflection off the image sensor. Coatings reduce reflections off the lens surfaces
to deliver crisp, undistorted digital images with natural colour balance.
Distant linked flash
Both lenses include new distance metering information, providing compatibility
with the E-TTL II flash system of the EOS 20D. When used in conjunction with
Canons range of EX Speedlite flash units, this allows for markedly improved
flash exposure metering.
An optional lens hood accessory is available for both lenses.