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Taken with EF 100-400mm f/4.5-5.6L IS USM

Optical Image Stabilizer Mode 2

panning of fast-moving subjects. Additionally,

and Mode 3

Mode 3 gives the equivalent effect of a shutter

The standard settings of the Optical Image

speed four stops faster, further positioning a

Stabilizer are set so that it is most effective

user for action photography.

when photographing stationary subjects. However

Hybrid Image Stabilizer

when panning with a moving subject is attempted

(tracking of the subject horizontally or vertically),

During normal shooting situa-

the shake-correction of the OIS may inadvertently

tions, sudden camera move-

over-compensate and interfere with framing. To

ment in rotational camera angle can cause

help resolve this, Canon developed Optical

significant image blur. During macro or close-up

Image Stabilizer Mode 2. In this mode, if you

photography however, the image blur caused by

move the lens to follow a subject for a pre-

linear camera shake—when the camera moves

determined time, the Optical Image Stabilizer

parallel to the subject—is more pronounced.

does not correct for the intentional panning

Optical Image Stabilizer is optimized to counteract

while continuing to correct any camera shake

rotational or angular camera shake and works

that's perpendicular to the panning motion. The

well for most camera shooting situations. To

result is a virtually smooth viewfinder image as

help compensate for linear camera shake, a new

you follow the moving subject. Optical Image

acceleration sensor determines the amount of

Stabilizer Mode 3 activates IS only when the

shift-based camera movement. The new Canon

shutter button is fully pressed, allowing for easy

Hybrid Image Stabilizer technology employs a

Linear Camera Shake

highly sophisticated algorithm that combines

the feedback of both the acceleration sensor

and angular velocity sensor (found in current

OIS technology) and moves the image stabilizer

lens elements, effectively compensating for both

rotational and linear camera shake. Hybrid IS

dramatically enhances the effects of Optical

Image Stabilizer especially during macro shooting,

which may be difficult for conventional image

stabilization technologies.

Diffractive Optics

with virtually instantaneous stops and starts.

Canon's use of diffractive optics (DO) results in

USM lenses also draw minimal power from the

high-performance lenses that are much smaller and

camera, ensuring longer battery life. Canon makes

lighter than traditional designs. Canon's unique

two types of Ultrasonic Motor lenses. Ring-type

multilayer diffractive elements are constructed

USM lenses, found in

by bonding diffractive coatings to the surfaces of

large aperture and super-

two or more lens elements. These elements are

telephoto designs, permit

then combined to form a single multilayer DO

manual focusing wit hout

element. Conventional glass lens elements disperse

first switching out of the

incoming light, causing chromatic aberration.

auto mode. Micro USM

The DO element's dispersion characteristics are

designs bring the perform-

designed to cancel chromatic aberrations at various

ance benefits of Canon's

wavelengths when combined with conventional

USM technology to a

glass optics. This technology results in smaller

wide assortment of

lenses with no compromise in image quality.

affordable EF lenses.

Canon has also developed a new triple-layer type

L-series Lenses

DO lens that uses an advanced diffractive grating

to deliver excellent performance, with superb

Most highly regarded among professional photog-

control of color fringing. This configuration is ideal

raphers, Canon L-series lenses are distinguished

for zoom lens optics and provides significant

by a bold red ring around the outer barrel. What

makes them truly distinctive, however, is their

remarkable optical performance — the result of

sophisticated Canon technologies, such as Ultra-

low Dispersion UD glass, Fluorite and Aspherical

elements and Super Spectra Coating.

Fluorite / UD Elements

Reducing color fringing, or chromatic aberration,

has been one of the great challenges in the design

of telephoto lenses. L-series telephoto lenses –

EF 400mm f/4 IS DO USM •f/4 • 1/1250 sec.

like the EF 70-200mm f/2.8 IS II USM and EF

Refractive Optical Element

300mm f/4L IS USM – employ Canon's Ultra-low

Chromatic aberrations

Refractive Optical Element

and Multi-Layer Diffractive

Dispersion glass to minimize this effect, providing

Optical Element Combined

much improved contrast and sharpness. Even

Image formation in the blue, green

and red wavelength order

more effective at suppressing chromatic aberration

Multi-Layer Diffractive Optical Element

Chromatic aberrations reversed from

that of a refractive optical element

Chromatic aberration canceled out

Image formation in the red, green and

blue wavelength order

Red

Green

Blue

Correction of Chromatic Abberation by the Multi-Layer

Anomalous

dispersion

Diffractive Optical Element.

reductions in size. A good example is the

EF 70-300mm f/4.5-5.6 DO IS USM lens, which

is 28 percent shorter than the EF 70-300mm

f/4-5.6 IS USM lens.

Comparison of optical characteristics between

Ultrasonic Motor

Canon developed the world's first lens-based

are Fluorite elements, used in high-end super-tele-

Ultrasonic Motor (USM) to power the lens autofocus

photo L-series lenses. Composed of crystallized

mechanism. Instead of large noisy drive trains

calcium fluoride (CaF

although costly, has roughly the corrective power

lenses employ the minute electronic vibrations

of two UD-glass elements, giving these L-series

created by piezoelectric ceramic elements. The

lenses their spectacular performance and relatively

focusing action of the lens is fast and quiet,

compact design.

EF LENSES

Aspherical Elements

Wide-angle lenses and fast normal-focal-length

lenses often suffer from spherical aberration.

When the light rays coming through the center

of the lens do not converge at the same point as

light rays coming through the lens edge, the

Ring-type USM

Spherical aberration

Convergence of parallel light

of spherical lens.

rays by an Aspherical lens.

image appears blurred because there is no sharp

Micro USM

point of focus. Canon's Aspherical elements use

a varying curved surface to ensure that the entire

image plane appears focused. Aspherical optics

also help to correct curvilinear distortion as one

might find in ultra wide-angle lenses. Canon

designs aspherical elements with extremely

precise variable curvature of one or both sides,

making possible lighter, more compact lenses.

Subwavelength and Fluorine

Anti-smear Coatings

The Subwavelength Coating (SWC) is a new

proprietary lens coating that helps control ghost

and flare to a

far greater

degree than

with earlier

coating tech-

nologies.

Utilizing SWC

technology on

EF 24mm f/1.4L II USM

f/6.3 •13 sec.

large-curvature

lens elements that are mainly found

in wide-angle lenses, will significantly minimize

Red

the occurrence of ghosting and flare caused by

Glass

Blue

reflected light in environments that have posed

problems. SWC is used on the latest Canon wide-

angle lens, EF 24mm f/1.4L II USM. The Fluorine

Red

anti-smear coating keeps soiling, smears and fin-

Blue

gerprints to a minimum for easy cleaning.

Fluorite

Focus Preset

optical glass and Fluorite

Focus Preset enables you to program a focusing

distance in the camera's memory. Normal picture

taking and focusing are unaffected by preset

), a single Fluorite element,

distances. For example, at a soccer game, you

Focus Preset the goal area. Shoot normally

elsewhere on the field, but once the action moves

toward the goal, the user can instantly return to

the preset distance by turning a ring on the lens.