Sigma 180mm f/3.5 EX IF HSM Macro Lens for Nikon SLR Cameras Dedicated to Nikon AF SLR cameras Takes life-size, 1:1 images, without the use of accessories Uses the silent HSM (Hyper Sonic Motor) Apochromatic design, 2 SLD (Special Low Dispersion) glass elements, floating inner focus system Chromatic, spherical aberrations, and astigmatism virtually eliminated