The DCR-7900ZD 0.79x wide angle lens is a high definition conversion lens made to broaden the field of view when attached on the digital camera"s lens, and it"s fabricated with two of the high index optical glass elements, resulting in a high resolution power of 230 lines/mm at center (MTF30%) at center. It achieved the level of almost non-distortion, 0.92% rate. It creates an unusually fine and non-distorted wide angle image. It can be mounted directly onto the camera"s 58mm filter thread. For others than 58mm filter thread camera or holder, apply the appropriately sized adapter ring (sold separately). -0.9% Super Low-Distortion designredline 230L/mm High Resolution Powerredline f=28mm Wideangle lens compatibleredline 2-group 2-element High Index glassredline Specifications & Measurements Magnification: Nominal 0.79x, Actual 079x Diagonal, 0.79x Horizontal Lens construction: 2-group/2-element, Coated optical glass elements Image distortion: -0.9%(max.wideangle) Front Filter thread: 92mm Mounting thread: 58mm(Interchangeable) Dimension: 33mm x 95mm Weight: 293g(10.3oz) Accessories Lens case Lens caps Instruction manuals How to exchange the adapter ring to the ring of other than 58mm thread.The DCR-7900ZD lens comes with an adapter ring of 58mm thread as an original package. When using with the camera of other than 58mm thread mount, please exchange the original adapter ring with the Raynox recommended adapter ring (sold separately) made to fit the specific camera. First, remove the original ring by turning it anti-clockwise. Mount the recommended ring turning in clockwise.