Sigma has introduced six lenses, five of which are compatible with the FourThirds mount.
The AP0 70-200mm f/2.8 EX DG Macro HSM lens can focus 100cm from the subject, providing a maximum magnification of 1:3:5.
Two Extraordinary Low Dispersion (ELD) and two Special Low Dispersion (SLD) elements are designed to rectify chromatic aberration, while multi-layer coating reduces the effects of flare.
The lens design means the length of the lens doesn?t change during focusing, and the Hyper Sonic Motor (HSM) ensures quiet and fast AF operation with manual focus override.
Sigma has yet to announce a price for the 70-200mm lens, which is compatible with optional 1.4x and 2x tele converters.
Sigma has also introduced the medium telephoto 105mm f/2.8 EX DG Macro lens with a FourThirds fitting. With a minimum focusing distance of 31.2cm and maximum magnification ratio of 1:1, the lightweight (450g) lens is suitable for macro photography.
A new lens coating is designed to reduce ghosting, while Sigma claims that the optical performance reduces lateral chromatic aberration and distortion.
Incorporated into the lens is a Focus Limiter Switch that limits the AF range, while the Dual Focus system ensures that the lens is comfortable to focus. The 105mm f/2.8mm lens retails for £339.99.
Retailing for £499.99 the new APO Macro 150mm f/2.8 EX DG HSM lens is compatible with the FourThirds mount. This compact and lightweight (895g) lens has a large aperture and can shoot 1:1 macro pictures.
Constructed from 16 elements in 12 groups, two SLD elements are designed to control chromatic aberrations. Meanwhile a floating lens system is used to move two different lens groups to different locations ? this is designed to compensate for astigmatic and spherical aberration.
Priced £369.99 the 18-50mm f.2.8 EX DC lens includes an SLD element and two aspherical lenses, which are designed to reduce chromatic aberration. Weighing 445g, the lightweight lens includes a Super Multi-Layer (SML) coating to reduce ghosting, and has a minimum focusing distance of 28cm.
The fifth lens launched is the 50-500mm f/4-3.6 EX DG/HSM lens, which includes four SLD elements to rectify chromatic aberration. Providing a 10x magnification, the lens employs a seven-group zoom system and, when used on a FourThirds camera, the focal length is 100-1000mm.
Retailing for £899.99, its other features include compatibility with 1.4x and 3x tele converters, Triple-cam Rear Focusing System and a zoom-lock switch.
Sigma?s final release also features a FourThirds fitting. Priced £319.99 and featuring a large aperture, the 30mm f/1.4 EX DC HSM includes two SLD elements to compensate for chromatic aberrations. Special coating reduces the effects of ghosting and flare and the HSM ensures fast AF performance.
To find out more about any of these products, visit www.sigma-imaging-uk.com or call 01707 329999.