VI. ACCESSORIES AND LENS
35
• Compensation optics lens barrel suspended by 3 springs that hold it in place in the
center, making it possible to eliminate the compensation optics retaining mechanism
in this IS unit
• Orientation of the compensation optics lens barrel along
the optical axis maintained using the force exerted by
angle-mounted springs and ceramic ball bearings (The
rotation of these ceramic ball bearings ensures that the
corrective optics are driven smoothly)
• Silicone resin damper fitted between the compensation
optics lens barrel and the supporting component (lens
group 2 lens barrel) damps harmful vibrations caused by
the extension and contraction of the springs and
improves IS performance
• Drive actuator for the compensation optics lens barrel constructed using the same
permanent magnets and coils used in existing IS units
• Construction of the new unit is based on the IS mechanism used in the PowerShot
SD700 IS Digital ELPH with design optimized for the characteristics of this lens
• Incorporating part of the lens group 2 lens barrel as a component of the IS unit makes
it possible to install the IS mechanism in a very limited space
• Automatically distinguishes between normal shooting and panning shots and selects
the optimum Image Stabilizer mode, a first for Canon IS lenses—vibration gyro used to
detect the difference between normal camera shake and panning movement—MODE
1/Normal and MODE 2/panning eliminated
• A tripod can be used with IS left ON (but switching OFF will still reduce power con-
sumption)
• Minimum focusing distance of 0.25m at all zoom settings
• Maximum magnification is 0.34x (at 55mm)
• Uses round EMD diaphragm for very good background blur quality (bokeh) and round
points of light
Compensation optics
movement
Compensation optics
Spring
Compensation optics
lens barrel
Ceramic ball
Damper
Structural Diagram of the IS
Unit Used in the
EF-S 18-55mm f/3.5-5.6 IS
(schematic)
