Wide
Zoom Lens
20-40mm f/2.8 EX DG ASPHERICAL
A
Large-aperture-wide-zoom lens from 20mm with large F2.8 aperture
SIGMA has created a new 20-40mm lens with F2.8 throughout its zoom range,
from ultra-wide 94.5 degrees to near-standard 56.8 degrees angle of view,
for photographers to shoot more creatively from various angles and zoom
perspectives. With a fast F2.8 maximum aperture superior peripheral brightness
is ensured. This lens is perfectly suited for indoor shootings even in
dim light without worrying about blurring in photos. These features also
make this lens desirable for use with Digital SLR Cameras.
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--
- 
30cm
minimum focusing distance throughout the zoom range
The lens' 30cm minimum focusing distance is useful for closeups, giving
photographers plenty of capability to use the zoom to adjust composition
and concentrate on detail, as desired. Maximum magnification is 1:4.6.
A short focus distance and a minimum aperture of F22 provides greater
depth of field.
Aspherical
lens compensates for aberration
Aspherical lens elements in front and rear lens groups compensate for
astigmatic and spherical aberration, respectively. By reducing aberration
to an absolute minimum, this SIGMA lens overcomes a major impediment to
zoom lens performance.
Sophisticated,
yet simple to use
Among the practical high-performance features of the lens are DF (Dual
Focus) mechanism for optimal handling stability during autofocus operation;
a wider-than-conventional focal ring for superior manual focusing operation;
and an inner focusing system that eliminates front lens rotation during
focusing, and allows use of the standard petal-type hood accessory, which
is excellent at blocking out extraneous light.
Lens
Construction |
|
17
Elements in 13 Groups |
Angle
of View |
|
94.5
- 56.8 degrees |
Number
of Diaphragm Blades |
|
9
Blades |
Minimum
Aperture |
|
F22 |
Minimum
Focusing Distance |
|
30cm |
Maximum
Magnification |
|
1:4.6 |
Filter
Size |
|
82mm |
|
Dimensions |
|
Diameter
89mm X Length 107.8mm |
Weight
|
|
600g |
SRP |
|
£649.99 |

|
20-40mm
f/2.8 EX DG ASP |
|
SIGMA |
|
|
|
CANON |
|
|
NIKON
(D) |
|
|
SONY |
|
|
PENTAX |
BACK
|