The Tamron SP 85mm F/1.8 is the world’s first* 85mm fast-aperture lens with image stabilization. Its delivers edge-to-edge viewfinder brightness for ease of composition and superior low-light performance. The fast aperture of the F/1.8 also offers the perfect balance of subject sharpness and bokeh, that dreamy blur which separates your portrait subject from the background. The 85mm focal length is ideal for producing a pleasing image with true-to-life facial features in accurate proportion. The SP 85mm F/1.8 uses LD (Low Dispersion) and XLD (Extra Low Dispersion) glass elements in the optical design to minimize color fringing and to achieve sharp and clear image quality with high color fidelity The SP 85mm F/1.8 is the world’s first* lens with a fixed focal length of 85mm and a fast aperture of F/1.8 that’s equipped with the VC system. This technology makes it possible to take photographs handheld in dim light and to make optimal use of slower shutter speeds and increased depth-of-field without extreme increase of the camera’s sensor sensitivity (ISO equivalent). Areas of possible ingress surrounding switches and the boundary between the focus ring and the lens barrel are protected by special seals. This provides deterrence against the intrusion of water droplets. Technical Specifications: Focal Length 85mm Maximum Aperture F/1.8 Angle of View (diagonal) 28 Degree33' for full-frame format 18 Degree39' for APS-C format Optical Construction 13 elements in 9groups Minimum Object Distance 0.8m (31.5 in) Maximum Magnification Ratio 1:7.2 Filter Size φ67mm Maximum Diameter φ84.8mm Length* 91.3mm （3.6 in) Canon 88.8mm (3.5 in) Nikon Weight 700g (24.7 oz.) Aperture Blades 9 (circular diaphragm**) Minimum Aperture F/16 Image Stabilization Performance 3.5 Stops (CIPA Standards Compliant) * Among 85mm F/1.8 interchangeable lenses for full-frame DSLR cameras as of January 2016. Data source: Tamron