Sigma 300-800mm f/5.6 EX DG APO IF HSM Digital AutoFocus Telephoto Zoom Lens for Olympus Four Thirds mount Digital SLR Cameras.

From 300mm telephoto to 800mm ultra-telephoto this new lens provides a constant fast maximum aperture and is optimized for digital SLR cameras.

This lens covers the telephoto range from 300mm to the ultra-telephoto range up to 800mm. By continuously varying the angle of view from 8.2° to 3.1°, the lens takes a lot of the footwork out of picture composition.

The new multi layer lens coating and lens design reduce flare and ghost, which is a common problem with digital cameras and also creates an optimum color balance.

Two ELD glass elements in the front lens elements reduce chromatic aberration to a minimum and also ensure sharp, quality images of high contrast.

The HSM models provide silent, high-speed and precise auto-focusing with full time manual focus override.

It also features a drop-in 46mm filter holder in the rear part of the lens barrel, which can be rotated to facilitate the use of filters, including a polarizing filter.

Since focusing and zooming do not change its overall length, this lens is easy to hold and use. In addition, since the front of the lens does not rotate, a circular polarizing filter can be easily attached and used.

When this lens is used with the 1.4x EX or 2x EX Apo Tele Converters (optional), it becomes a 420-1120mmF8 MF lens or a 600-1600mm F11 MF lens respectively.