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VII.NEW ACCESSORIES AND LENSES
Canon EF-S18-200mm
f/3.5-5.6 ISlens
This new high magnification, wide-to-telephoto EF-S zoom lens is the ideal kit lens for the
EOS 50D,offering a 35mm equivalent focal length of 29mm to 320mm (11x), and featuring
Canon’s advanced Optical Image Stabilizer technology.It is also available separately and is
compatible with all Canon DSLRs using APS-C sized sensors, including the EOS 40D,
30D,20D, and all versions of the EOS Digital Rebel and Rebel series cameras.
The compact size and weight on this lens, plus its professional lens design and construction,
improved AF speed and advanced IS system make it an extraordinary value for the price.
The optical arrangement includes two UD glass elements and two high-precision GMo
(Glass Molded) aspherical lenses among the total of 16 lead-free glass elements in 12 groups.
These UD and aspherical lens elements help reduce distortion and chromatic aberrations.
Close-focus performance is excellent: the lens focuses down to about 1.5 feet (0.45m),where
it can fill the frame with a subject about the size of a book of matches. In addition,S uper
Spectra Coatings on all elements help to minimize lens flare and ghosting.
Canon’s advanced Optical Image Stabilizer technology increases the lens stability by up to
4 shutter speeds,essential ly extending the performance of the lens in low-light situations
to that of more expensive f/2–f/2.8 non-stabilized lenses. For example,at 200mm focal
length,the recommended lowest shutter speed for sharp photos is 1/200 sec. But with the
IS turned on, most photographers will be able to take sharp photos at speeds as slow as
1/30th sec.or e ven 1/15th sec.,allowing creative control of the aperture to increase depth
of field,balance the ambient lighting to reduce underexposed backgrounds, or increase
motion blur as desired.
EMD
at 200mm
Focusing Ring
Hood Mount (Bayonet)
Zoom Ring
Rubber ring
Silver ring Contact
Image stabilizer switch
Focus mode switch
Zoom Index
Closest focusing
distance mark
Zoom ring lock lever
IS unit
Externaland Cross Section of EF-S 18-200mm f/3.5–5.6 IS