Focal Length & Maximum Aperture of 100mm 1:2.8Lens Construction is made up of 15 elements in 12 groups.Diagonal Angle of View of 23.4°Inner focusing system with USM.Full-time manual focus available.Closest Focusing Distance 0.99 ft./0.3m (maximum close-up magnification: 1x).* World’s First* Medium Telephoto Macro Lens with a Maximum Magnification of 1.4x.* High Image Quality and Bright, fixed f/2.8 Aperture Telephoto Macro RF Lens* Optical Image Stabilizer with up to 5 Stops of Shake Correction**.* Hybrid IS Compensates for Angular and Shift Camera Shake during Macro Shooting.* Spherical Aberration (SA) Control Ring Allows Adjustments to Shape and Character of Foreground/Background Bokeh