EF-S 10-22mm f3.5-4.5 USM
The EF-S 10-22mm f3.5-4.5 USM is ideal for landscape or indoor photography, and for photographers wishing to experiment with pan-focus and dramatic perspective effects. It also has a remarkably close focusing distance of just 24cm. With similar high build quality to the EF-S 17-85mm f4-5.6 IS USM, the EF-S 10-22mm f3.5-4.5 USM includes a Super UD (ultra-dispersion) glass lens band two aspherical elements. The non-rotating front element makes it ideal for use with filters such as polarizing and graduated, both of which are poular for the type of landscape photography to which the lens is suited.
The lens features Canon's EF-S lens mount, matched to the EOS 20D and EOS 300D digital SLRs. The APS-C sensor of these cameras is smaller than a 35mm film frame. This changes the field-of-view between the two formats. The EF-S 10-22mm gives a similar view to a 16-35mm lens on a 35mm camera.
The EOS 20D and EOS 300D are compatible with all EF lenses, while EF-S lenses only fit these two cameras. The 'S' in EF-S stands for '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 EF-S lenses from EF lenses, which retain their traditiional 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 btoh lenses employ ultrasonic frequency vibrations to drive focusing with unrivalled speed. Canon's 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 new lenses are tailored to specifically match the EOS 20D and EOS 300D. Both lenses also feature full-time manual focus overide.
The lens incorporates 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 a subject.
Perfect for digital
By optimising lens caotings, Canon's 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.
Both lenses include new distance metering information, providing compatibility with the E-TTL II flash system of the EOS 1D Mark II, 20D, 30V Date, 33V and 300X. When used in conjunction with EX Speedlite flash units, this provides improved flash exposure metering.
An optional lens hood accessory is available for both lenses. In keeping with Canon's stringent environmental policy, only lead-free glass is used in the lens' optics.
Diagonal angle of view: 107°30' to 63°30'
AF drive system: Ring USM
Manual focusing: Enabled with focus mode switch and focusing ring (full time manual focusing)
Focusing range: 0.24m to infinity
Maximum magnification: 0.08x(wide); 0.17x(tele)
Minimum aperture: f22 to f27
Aperture blades: 6 (circular type)
Filter diameter: 77mm
Diameter x length: 83.5 x 89.8mm
Lens hood/lens cap: EW-83E/E-77U
Lens case: LP1319
Lens extender EF: not compatible