Digital
Camera Lens
17-50mm f/2.8 EX DC OS HSM
Large
aperture standard zoom lens with a minimum focal length of 17mm, designed
exclusively for digital SLR cameras and incorporating Sigma's original
Optical Stabiliser system.
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The
OS function offers the use of shutter speeds approximately 4 stops slower
than would otherwise be possible. The lens has a compact construction
with an overall length of 91.8mm making it ideal for travel photography.
Two FLD (“F” Low Dispersion) glass elements, two glass mold
and one hybrid aspherical lens provide excellent correction for all types
of aberrations. This lens has superior peripheral brightness and provides
sharp and high contrast images even at the maximum apertures. The incorporation
of HSM (Hyper Sonic Motor) provides fast and quiet AF.
FLD
(“F” Low Dispersion) glass elements
FLD glass is the highest level low dispersion glass available with extremely
high light transmission. This optical glass has a performance equal to
fluorite glass which has a low refractive index and low dispersion compared
to current optical glass. It also benefits from high anomalous dispersion.
These characteristics give excellent correction for residual chromatic
aberration (secondary spectrum) which cannot be corrected by ordinary
optical glass and ensures high definition and high contrast images.
This
lens incorporates two FLD glass elements, which compensate for colour
aberration. In addition, two glass mold elements and one hybrid aspherical
lens give excellent correction for field curvature and astigmatism. High
definition images are ensured throughout the entire zoom range .
Sigma’s
unique Optical Stabiliser technology
The lens is equipped with Sigma’s own unique OS function. This system
allows the photographer to use shutter speeds approximately 4 stops slower
that would otherwise be possible.
Large aperture throughout the entire zoom range
The large F2.8 aperture allows the use of fast shutter speeds and provides
a bright viewfinder image, helping the photographer confirm accurate focusing.
It is also ideal for emphasizing the subject by creating a natural, blurred
background.
Covering a wide range of focal lengths
This lens covers a wide range of focal lengths from 17mm and has an equivalent
angle of view of a 25.5-75mm with a 35mm SLR camera. It is ideal for general
photography as well as portraits and landscapes.
* The angle of view varies depending on which camera the
lens is mounted on.
Compact construction
The lens has a compact construction with a diameter of 83.5mm, overall
length of 91.8mm and weight of 565g. This compact and lightweight construction
makes it ideal for travel photography.
Super Multi-Layer Coating and superior
peripheral brightness
The Super Multi-Layer Coating reduces flare and ghosting as well as providing
sharp and high contrast images throughout the entire zoom range.
This lens also benefits from superior peripheral brightness and provides
sharp and high contrast images even at the maximum apertures.
Fast
and quiet AF with internal focusing
The lens incorporates HSM (Hyper Sonic motor), ensuring fast and quiet
AF. The inner focusing system eliminates front lens ration, making the
lens particularly suitable for using the supplied petal-type hood and
circular polarising filters.
* For Pentax mount, AF will not function with DSLR cameras
that do not support HSM.
Close
focusing capability
This lens has a minimum focusing distance of 28cm throughout the entire
zoom range and a maximum magnification ratio of 1:5.
Rounded
diaphragm
This lens has rounded 7 blade diaphragm which creates an attractive bokeh
to the out of focus area of the image.
* Vignetting will occur if the lens is
used with digital cameras with image sensors larger than APS-C size or
35mm SLR cameras.
Lens
Construction |
|
17
Elements in 13 Groups |
Angle
of View (SD Format) |
|
72.4
- 27.9 degrees |
Number
of Diaphragm Blades |
|
7
Blades (Rounded diaphragm) |
Minimum
Aperture |
|
F22 |
Minimum
Focusing Distance |
|
28cm |
Maximum
Magnification |
|
1:5 |
Filter
Size |
|
77mm |
|
Dimensions |
|
Diameter
83.5mm X Length 92mm |
Weight
|
|
565g |
SRP |
|
£689.99 |

| 17-50mm
f/2.8 EX DC OS HSM |
|
SIGMA |
| |
|
NIKON |
|
|
CANON |
17-50mm
f/2.8 EX DC HSM |
|
SONY |
| |
|
PENTAX |
BACK
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