(From Sigma lens literature) Fast maximum aperture ƒ/2.8 300mm telephoto lens optimized for digital SLR cameras. The new multi layer lens coating reduces flare and ghost, which is a common problem with digital SLR cameras. ELD (Extraordinary Low Dispersion) glass elements reduce chromatic aberration to a minimum and also ensure sharp, quality images of high contrast. It creates an excellent image quality with 35mm film SLR cameras as well as digital SLR cameras.
This new lens has a special coating to reduce internal reflection and minimize flare and ghost, which is a common problem with digital cameras and also creates an optimum color balance.
This lens uses two ELD glass elements reduce chromatic aberration to a minimum and also ensure sharp, quality images of high contrast.
A drop-in 46mm filter holder in the rear part of the lens barrel can be rotated to facilitate the use of filters, including a polarizing filter.
The HSM models (Sigma, Nikon and Canon mounts) provide fast, silent AF function as well as full- time manual focus override.
It also incorporates inner focusing system, which enables responsive and fast auto focus speed. The overall length of the lens does not change during focusing, ensuring convenient handling and ease of use.
Simply adding an APO teleconverter (optional extra), means that this lens can be used as a 420mm ƒ/4 AF ultra-telephoto lens with a 1.4X EX teleconverter, or a 600mm ƒ/5.6 AF ultra-telephoto lens with a 2X teleconverter.