About Sigma Zoom Telephoto 100-300mm f/4 (D) EX IF Autofocus Lens for Sony Alpha & Minolta Maxxum Series:
The Sigma 100-300mm f/4 (D) EX IF telephoto zoom lens provides a large constant f/4 maximum aperture at all focal lengths. The use of Apochromatic design and four SLD (Special Low Dispersion) glass elements give full correction of chromatic aberration and provide a high level of optical performance.
An inner focusing system eliminates front lens rotation, making the lens particularly suitable for using the petal-type lens hood supplied and circular polarizing filters. Since focusing and zooming do not change its overall length, ease of handling and operation is assured. A removable tripod mount is provided with the lens. Handholding is easy since focusing and zooming do not change its overall length.
The improved (D) lens design corrects for various aberrations. This lens is specially coated to get the best color balance whilst cutting down on ghosting caused by reflections from the digital image sensor. The lens provides the utmost correction against lateral chromatic aberration which is a serious problem for digital SLR cameras.
It is also possible to use this lens with Sigma 1.4x EX and 2x EX APO Tele Converters to convert it to an ultra tele-zoom lens.
EX lens series denotes excellence of engineering and technology
Materials used in this lens are lead- and arsenic-free ecological glass