System Brochure

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usa.canon.com/eos
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EF LENSES
15mm Fisheye
FOCAL LENGTH COMPARISON
Floating System
Typical lenses correct for optical aberrations
only at commonly used focusing distances. Not
surprisingly, at other focusing distances, espe-
cially close range, aberrations can compromise
image quality. Rather than using fixed spacings,
Canon’s floating system dynamically varies
the gap between key lens elements based
on focusing distance. Most aberrations are
effectively suppressed throughout the focusing
range, assuring high image quality in all
shooting situations.
Circular Aperture
Canon lenses featuring circular aperture
diaphragms employ curved blades to create
a smoothly rounded opening as the lens is
stopped down. As a result, most out-of-focus
background highlights are rendered as
natural-looking rounded shapes rather than
as distracting polygons. These lenses deliver
smooth, consistent stop-down action (even at
14.0 fps), near-silent operation and excellent
optical characteristics.
Inner and Rear Focusing
An inner focusing lens has the focusing lens
group(s) in front of the diaphragm, while a
rear focusing lens has the focusing lens group(s)
behind the diaphragm. Both designs allow for
compact optical systems that produce faster AF.
And because the front of the lens does not rotate
to focus, filter orientation remains constant.
AF Stop Feature
Pressing the AF Stop button (featured on several
EF IS telephoto lenses) momentarily locks the
AF to help prevent the focus from shifting to a
passing obstruction. After the obstruction has
cleared, the focus will still be on the subject, and
you can quickly resume shooting. AF Stop buttons
are positioned at four locations around the lens
grip for easy access.
Full-Time Manual Focusing
Canon EOS cameras with EF lenses deliver
impec-cable AF precision. Manual focusing
capability, nevertheless, can enhance
flexibility. Canon EF lenses with full-time
manual focusing enable the photographer to
manually tweak focus without switching out
of AF mode. Since AF action does not cause
the focusing ring to turn, it can be made wider
for improved grip and comfort.
Specialty Lenses
Fisheye — With its unique focal length range,
the EF 8–15mm f/4L Fisheye USM is the world’s
widest fisheye zoom lens. It delivers 180°
diagonal angle of view images for all EOS SLR
cameras with imaging formats ranging from
full-frame to APS-C, and provides 180° circular
fisheye images for full-frame EOS models. This
new Canon lens has a wide zoom range feature
that provides a truly elevated level of creativity
and performance for users shooting artistic
compositions or panoramic landscapes, as
well as astronomy and sports.
EF-S lenses — Designed for the Canon EOS 7D,
EOS 60D and all EOS Rebel models with APS-C
sized sensors with a 1.6x crop factor, Canon’s
EF-S lenses take advantage of the camera
sensor’s smaller size to help deliver optimized
performance in compact, lightweight designs.
EF-M lenses — Even more compact, and
designed to complement the new EF-M lens
mount found on the EOS M Digital Camera,
EF-M lenses bring superb EOS optics and
performance to an even smaller package.
TS-E — TS-E lenses are capable of tilt and
shift movements, which bring many of the
advantages of technical view cameras to the
EOS System. Tilt movements alter the angle of
the plane of focus between the lens and film
plane, making broad depth-of-field possible
even at larger apertures; shift movements
slide the lens’s optical axis along the film/
sensor plane, enabling photographers to
correct or alter perspective at almost any angle.
Macro — Canon’s EF lens lineup has a number
of options for true close-up and macro photog-
raphy. With five macro lenses for precision,
and three screw-on close-up lenses for conve-
nience—in addition to the Life-Size Converter EF
and two Extension Tubes—Canon’s macro lenses
and close-up accessories can uncover detail that
is nearly impossible for the unaided human eye
to detect.
EF Mount
The Canon EF and EF-M mount are much more than
simply a way to attach a lens to a camera body. As
the communication conduit between camera and
lens, this fully electronic mount enables high-
speed autofocus, precise aperture control and
preview, makes automatic compensation with
lens extenders possible and can communicate
data such as focal length, lens model, even
serial number for in camera processing and
recording. Ready for the future, the EF mount
offers both forward and backward compatibility
Dust- and Water-Resistant
Construction
Most L-series EF
telephoto lenses are
highly dust- and
water-resistant
thanks to rubber seals
at the switch panels,
exterior seams, drop-
in filter compartments
and lens mounts.
Moving parts, such as
the focusing ring and
switches, are also designed to help keep out
environmental contaminants, providing reliable
performance under harsh conditions.
Reverse tilt and shift greatly reduces the range on which focus-
ing is possible.
With a normal lens With a TS-E lens
Astigmatism
Floating Effect
(TS-E 24mm f/3.5L)
Closest
shooting
distance
TS-E 24mm f/3.5L Floating System
Floating
Focal plane
The lens’s tilt mechanism is used to achieve a pan focus effect
that allows focusing all the way back.
Shift was used to adjust the image to keep the building
perpendicular all the way to the top.
Without using shift causes the image of the building to lean in
at the top.
Tilt Movements – Using a normal lens, shallow or deep focus is
controlled by the size of the aperture used to adjust depth-of-
field. Canon TS-E lenses can help achieve this by the tilting of
the lens barrel in relationship to the focal and subject planes.
This allows for the appearance of extremely deep focus even at
wide open apertures, and shallow focus at smaller apertures.
Shift Movements – By keeping the camera level, and
using the shift function to raise the lens instead, this
perspective effect can be corrected. With the camera’s
focal plane set parallel to the building, shifting the lens
upward will obtain a more rectangular-looking building.
About Macro Magnification
A life-size macro lens—that
is, a 1x magnification—
records an image on film at
its actual size. If you’re
photographing fruits, for
example, and it has a diam-
eter of 1 in., it will occupy 1
in. of your actual slide or
negative. With a digital
SLR, at 1.0x magnification,
the image projected onto
your camera’s sensor will
likewise be the same size at
the sensor plane as the
actual subject itself. Other
macro lenses have lower or
higher magnifications. A
lens with 0.5x magnifica-
tion will produce an image
on film that is half the
size of the actual subject.
Your 1 in. fruit then would
only occupy 0.5 in. on film.
In the other direction, a 5x
magnification lens will con-
vert the 1-in. fruit to a 5-in.
diameter image. Since the
entire image won’t fit in the
frame of your film, you will
have an enlarged image of
a detail of the fruit.
Magnification is not the
same as focal length. A
50mm lens and a 180mm
might both be macro lenses
with, for example, 1.0x
magnification. The advan-
tage of the longer lens is
that it allows greater dis-
tance from a subject, while
allowing the same magnifi-
cation in the final image. The 180mm lens is ideal for shoot-
ing tiny subjects without disturbing them; the 50mm is bet-
ter choice for copying flat documents.
0.5x
1.0x
0.25x
5.0x
3.0x
EF 24mm f/1.4L II USM •f/2.8 •1/30 sec.
14mm 17mm 20mm 24mm 28mm 35mm 50mm 70mm
85mm 100mm 135mm 200mm 300mm 400mm 500mm 600mm 1200mm
Depth-of-field with tilt movements
Plane of optimum focus
Film plane
Using Tilt Movements to Focus an Oblique Subject Plane
Using Shift Movements to Focus Tall Building
TS-E Movements
Tilt Movements alter the angle of the plane of focus between the lens and focal plane, and Shift Movements move the lens’s
optical axis in parallel.
180°
114°
104° 94° 84°
75° 63° 46° 34°
28° 30' 24° 18° 12° 8° 15' 6° 10' 5° 4° 10' 2° 5'
EF 8–15mm f/4 Fisheye USM
•
f/4
•
1024 sec.
EF 8–15mm f/4 Fisheye USM
•
f/5.6
•
1/200 sec.
Focal Length: 8 mm Approx. 10 mm
Approx. 12 mm Approx. 15 mm
Full size
Circular fisheye
APS-C
Full-frame fisheye
APS-H
Full-frame fisheye
Full size
Full-frame fisheye
The diagram below shows the relationship between each
image size and a 180˚ angle of view for each focal length.
*The red circle for each forcal length is the size of a 180˚ angle of
view on the image plane.
with new lens technologies such as USM and
Hybrid IS—and new optical designs, such as EF-S
lenses and Cinema EOS lenses as they are devel-
oped by Canon. Similarly, the EF-M mount, found
on the new EOS M Digital Camera, offers all the
same communication points as the EF mount, and
is compatible with all EF and EF-S lenses when
used with an optional adapter.