Sigma Press release.

The Sigma Corporation is pleased to announce the launch of the new APO 70-200mm F2.8 II EX DG MACRO HSM.
This large aperture zoom lens has improved optical performance and retains close-up ability with a minimum focusing distance of 100cm/39.4in and maximum magnification ration of 1:3.5. This lens is suitable for taking all type of subjects such as portraits, landscape, and close-up pictures. Two SLD (Special Low Dispersion) and three ELD (Extraordinary Low Dispersion) glass elements provide excellent correction for all types of aberrations. High image quality is assured throughout the entire zoom range. The super multi-layer coating reduces flare and ghosting. This lens incorporates HSM (Hyper Sonic Motor), which ensures a quiet and high-speed AF as well as full-time manual focusing capability. The lens design incorporates an inner focusing and inner zooming systems. The overall length of the lens does not change during focusing and zooming, ensuring convenient handling. A removable tripod collar (TS-21) is included as a standard component. When this lens is used with the optional 1.4x EX DG APO or 2x EX DG APO Tele Converters, it becomes a 98-280mm F4 AF telephoto zoom lens or a 140-400mm F5.6 AF telephoto zoom lens respectively.

Press Release:

The Sigma Corporation is pleased to announce the launch of the new APO 50-150mm F2.8 II EX DC HSM lens.
This large aperture telephoto zoom lens is designed exclusively for digital SLR cameras with APS-C size sensors and its compact, lightweight body provides freedom of movement and versatility. The minimum focusing distance of 100cm/39.4in. and the high-resolution power layout have improved the strength of the lens in close-up photography. This lens offers a large aperture of F2.8 and its large depth of field offers greater freedom of creative expression. It has a maximum aperture of F2.8. Four SLD glass elements are used for maximum correction of chromatic aberrations. The super multi-layer lens coating reduce flare and ghosting and ensure sharp images throughout the entire zoom range. The lens design incorporates an inner focusing and inner zooming system. As the overall length of the lens does not change during focusing and zooming, convenient handling is ensured. The HSM (Hyper Sonic Motor) system allows quiet and high-speed auto focusing with full time manual focus override by just rotating the focusing ring. The addition of the optional 1.4x EX DG APO or 2x EX DG APO Tele Converters produce a 70-210mm F4 AF tele-zoom lens and a 100-300mm F5.6 AF ultra-telephoto zoom lens respectively.

* Vignetting will occur if the lens is used with digital cameras with image sensors larger than APS-C size or 35mm SLR cameras.

Sigma 50-150mm Press release.