Canon CN-E30-105mm T2.8 L S Brochure (en)

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EF LENSES
Full-Time Manual Focusing
Canon EOS cameras with EF lenses deliver 
impeccable 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. 
15mm Fisheye
FOCAL LENGTH COMPARISON
Specialty Lenses
Fisheye — With its unique focal length range, 
the EF 8–15mm f/4L Fisheye USM offers an 
interesting and exciting perspective. 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 
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 Mark II, EOS 70D 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. 
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’  
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  
photography. With six macro lenses for  
precision, and three screw-on close-up lenses 
for convenience – 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 mount is 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  
Reverse tilt and shift greatly reduces the range on which  
focusing 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’ 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 shift, the image of the building leans 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  
diameter of 1 in., it will 
occupy 1 in. of your actual 
slide or negative. With a 
digital SLR camera, 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 magnification 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  
convert 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 
advantage of the longer 
lens is that it allows greater 
distance from a subject, 
while allowing the same 
magnification in the final image. The 180mm lens is ideal for 
shooting tiny subjects without disturbing them; the 50mm is 
better choice for copying flat documents.
0.5x
1.0x
0.25x
5.0x
3.0x
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 a 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’ 
optical axis in parallel.
180°
114°
104°
94°
84°
75°
63°
46°
34°
28° 30'
24°
18°
12°
8° 15'
6° 10'
4° 10'
2° 5'
EF 8
15mm f/4L Fisheye USM • f/5.6 • 1/200 sec.
Focal Length: 8mm
Approx. 10mm
Approx. 12mm
Approx. 15mm
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 focal length is the size of a 180˚ angle of 
  view on the image plane.
EF 8
15mm f/4L Fisheye USM • f/4 • 1024 sec.
in-camera processing and recording. Ready  
for the future, the EF mount offers both 
forward and backward compatibility with 
lens technologies such as USM and Hybrid IS, 
as well as new optical designs, such as EF-S 
lenses and Cinema EOS lenses as they are 
developed by Canon.
Floating System
Typical lenses correct for optical aberrations 
only at commonly used focusing distances.  
Not surprisingly, at other focusing distances,  
especially 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 can be effectively suppressed 
throughout the focusing range, helping to assure 
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.
Dust- and Water-Resistant  
Construction
Most L-series EF  
telephoto lenses  
are 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.