The Sinar Tele-Xenar 180MM F/2.8 PQS Lens is best suited for rapid focusing in portraiture, fashion, and people photography.Using a wide aperture, this Xenar lens neutralizes the obtrusive background by selective focusingIt is compatible with most Sinar cameras and is suitable for low-light photographyThe focal length is 180 mm and the aperture range is 2.8-22