Brochure

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Camera shake correction mechanism OFF
Camera shake correction mechanism ON
Original SIGMA technology
that counteracts camera shake
Optical Stabilizer (OS)
SIGMA’s original Optical Stabilizer (OS) technology
uses two sensors inside the lens to detect vertical
and horizontal motion. By adjusting particular lens
elements, the OS compensates for the detected
movement, thereby minimizing the blur caused by
camera shake. In addition, since stabilization takes
place within the lens, what you see in the viewnder
is the resulting stabilized image. As a result, you can
confidently judge focus and composition. Two OS
modes are available, depending on the lens. Mode
1 detects and corrects vertical and horizontal mo-
tion, making it ideal for shooting with the camera in
a fixed position. Mode 2 detects and corrects only
vertical motion, making it ideal for panning, as when
shooting motorsports, for example.
In addition, on certain SIGMA lenses, the OS (Optical
Stabilizer) function features an acceleration sensor
to ensure even higher precision. In Mode 2, the ac-
celeration sensor teams up with the Intelligent OS
and its updated stabilization algorithm to deliver
effective stabilization while you move the camera
horizontally, vertically, or diagonally—regardless of
the position of the lens. This feature helps ensure
effective panning and outstanding capture of moving
subjects.
Designed to optimize bokeh near
maximum aperture
Rounded diaphragm
The polygonal shape of a conventional iris dia-
phragm causes out-of-focus light points to appear
polygonal. A rounded diaphragm is designed to pro-
duce rounded out-of-focus light points when opened
to near maximum aperture. This creates attractive
bokeh effects in many situations, such as when pho-
tographing a subject against an out-of-focus surface
of water from which light is being reected.
AF drive motor for rapid focusing
and quiet operation
Hyper Sonic Motor (HSM)
The Hyper Sonic Motor (HSM) is an original SIGMA
development that uses ultrasonic waves to drive the
autofocus mechanism. Its extremely quiet operation
helps avoid disturbing photographic subjects. High
torque and speed assure rapid autofocus response.
SIGMA uses two types of HSM: ring HSM and micro
HSM. The Ring HSM configuration permits manual
ne tuning of focus (manual override) by turning the
focusing ring after autofocus is complete.
Fast AF response and precise focusing control
Stepping Motor
A stepping motor operates in synchronization with
pulse signals, enabling fast AF response and fine,
precise focusing control. The motor is also very qui-
et, enabling comfortable AF for both stills and video.
Stepping motors tend to be small and light, helping
to keep lenses more compact.
A type of polycarbonate with a thermal
expansion rate similar to that of aluminum
TSC (Thermally Stable Composite)
TSC is a type of polycarbonate with a thermal expan-
sion rate similar to that of aluminum. This is import-
ant because when parts made of multiple materials
with different thermal expansion rates are used in
combination, especially moving parts, it is necessary
to keep a large clearance between the parts. This is
due to the large difference in dimensional change
caused by temperature, which results in a decrease
in assembly accuracy.
By using TSC, the clearance between the polycar-
bonate and aluminum alloy parts can be minimized,
making it possible to realize a lightweight lens barrel
with high accuracy.
A composite material that is both
light and strong
CFRP (Carbon Fiber Reinforced
Plastic )
This is a composite material containing polycarbon-
ate and carbon fiber. It is used in the interior and
exterior fittings of aircraft, among many other ap-
plications, as it is light and strong. CFRP is used by
SIGMA in lens production, such as for lens hoods.
Ensuring a more stable AE performance during
high-speed continuous shooting
Electromagnetic diaphragm
mechanism
An electromagnetic diaphragm mechanism allows
a lens to receive electronic signals from the camera
body for more precise diaphragm control. This fea-
ture ensures a more stable Auto Exposure (AE) per-
formance during high-speed continuous shooting.
Preventing dust and dirt from entering
Dust and Splash Resistant Structure
For all Sports line and some Art line products, a
highly effective dust and splash resistant structure
is built into the lens barrel. This includes special
sealing at the mount connection and cover connec-
tion, and around the manual focus ring and zoom
ring, which prevent dust and dirt from entering.
Lenses with dust and splash resistant structure are
ideal for photographers who work in difcult weather
conditions.
For all Contemporary and Art line lenses, the lens
mount incorporates rubber sealing to reduce the risk
of water or dust contamination around the connec-
tion between the camera and lens.
*1 There is no sealing on the lens mount for the SIGMA SA mount
lenses as the sealing is available on the mount of the camera body.
*2 Although this construction allows the lens to be used in light
rain, it is not the same as being waterproof, so please prevent large
amounts of water from splashing on the lens. It is often impractical
to repair the internal mechanism, lens elements and electric com-
ponents if they are damaged by water.
MF adjustments can be made, even when using AF
MO (Manual Override)
When the Focus Mode Switch is set to the MO posi-
tion, manual focus adjustments can be made simply
by rotating the focus ring, even when using AF.