Sigma 15-30mm F/3.5-4.5 Ex Dg Lens (canon Af). Sigmas 15-30mm f/3.5-4.5 EX Aspherical DG DF provides an excellent 15mm ultra-wide angle to 30mm wide-angle focal length, one of the first of its kind. This lens has minimum focusing distance of 30cm at all focal lengths with 110.5 degrees (wide) to 71.6 degrees (tele) angle of view. (Maximum magnification is 1:6.) It incorporates a hybrid aspherical lens in the front lens group to minimize distortion and astigmatism, and molded glass aspherical lens in the rear lens group to minimize spherical aberration thus improving the clarity and sharpness of your images. Also, the lens comes equipped with a dual focus mechanism and also inner focusing system. It is ergonmically designed and easy to hold, since the focusing ring does not rotate during auto focusing, and yet it provides adequate torque of the focusing ring during manual focusing the lens. Sigmas 15-30mm f3.5-4.5 EX Aspherical DG DF has a new mechanical design which has six groups zoom system. This new mechanical design will minimize astigmatism for all focal lengths. The iris diaphragm has 8 blades to obtain a fantastic, 'out focus' of image in the foreground and background. If required this lens can be used on most digital SLR models. However the range of the lens will be slightly changed at approximately 22.5mm-45mmm on many models. Specification Focal length: 15-30mm Maximum aperture: f/3.5-4.5 Lens construction: 17 elements in 13 groups Focusing system: Internal Focusing Angle of view: 110.5°-71.6° Number of diaphragm blades: 8 Minimum aperture: f/22-32 Minimum focusing distance: 30cm Maximum magnification: 1:6 Filter size: Rear (gelatin filter insert type) Lens hood: Petal shape hood (non-removable) Dimensions: 87mm (diameter) x 130mm (length) Weight: 615g
Super Multi Coating reduces flare and
ghosting that tends to occur when using digital SLR cameras.
It covers from 15mm ultra-wide angle to
30mm wide-angle.
Sigma provides the new ultra-wide angle zoom lens from 15mm
and this lens is the first of its kind in the world. It can be useful for images
of landscapes, large buildings, group photographs or even more. The perspective
that changes with the angle-of-view gives picture an extraordinary feeling.
Minimum focus distance with 30cm
(11.8 in.) at all focal length
Delicate compositions can be adjusted by lens zooming and this
is helpful for close-up photography. Provides deep depth of field with its short
focal length for amazing photographic expressions.
Desirable for digital SLR
cameras
This is an ultra-wide zoom lens that covers a large wide-angle
range from 15 mm to 30 mm. With a minimum focusing distance of 30 cm(11.8
inches) throughout the entire zoom range, it is an ideal lens for Digital SLR
Cameras.
Aspherical lens for distortion
correction
It incorporates hybrid aspherical lens in the front lens group
to minimize distortion and astigmatism, and molded glass aspherical lens in the
rear lens group to minimize spherical aberration. Minimization of the distortion
is a most important issue for zoom lens, but Sigma has succeeded, to provide
image quality with minimal distortion by employing aspherical lenses.
Inner focus system
This lens incorporates an internal focusing system, which
eliminates front lens rotation. Since focusing do not change its overall length,
this lens is easy to hold and use. Also it is allowing the use of a Petal-type
Hood.
Handling
The lens also incorporates Dual-Focus (DF) mechanism. It is
easy to hold the lens, since the focusing ring does not rotate during
auto-focus, yet it provides adequate focusing torque of the focusing ring during
manual focusing of the lens.
