This rectilinear 15-30mm f3.5-4.5 EX Aspherical DG DF lens provides
focal lengths from 15mm ultra-wide angle to 30mm wide-angle and is the
first of its kind in the world. This lens has minimum focusing distance
of 11.8 inches (30 cm) at all focal lengths with 110.5 degrees (wide)
to 71.6 degrees (tele) of angle of view. (Maximum magnification is
1:6.)
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.
This
lens equipped with dual focus mechanism and also inner focusing system.
It is easy to hold the lens, 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.
This lens is
desirable and for digital SLR cameras also. Its effective zoom range
will be 22.5mm-45mm wide angle zoom lens on most SLR digital cameras.
Sigma 15-30mm f3.5-4.5 EX Aspherical DG DF has a mechanical design
which has six groups zoom system. This mechanical design will minimize
astigmatism for all focal lengths.
This lens is equipped with a
non-removable type lens hood (Petal-shaped) to prevent extraneous light
harmful for image quality. This lens uses rear gelatin (insert type)
filters. The iris diaphragm has 8 blades to obtain beautiful out focus
of image in the foreground and background. |
