The NiSi Close Up Lens Kit NC 58mm is an excellent adapter for achieving a closer minimal focusing distance. Magnification Depending on the focal length of the lens you use the magnification will vary with longer focal lengths giving higher magnification. The diopter is a +5 lens that is constructed using double optical corrective glass with a muti-nano coating and apochromatic design. This provides advanced quality with a natural colour and minimal purple or green fringing for in-focus areas and blur. Compatibility At a focal length of 120mm the magnification is 1:1. Designed to work with a range of lenses the NC 58 close up kit has zero vignetting at 35mm on a full frame sensor and even down to 24mm on an APS-C camera sensor. The adapter will fit directly onto lenses with a 58mm filter thread. It has been designed to suit prime, zoom and macro lenses between 24-250mm on APS-C; or 35-250mm on full frame. It will work with macro lenses with a 58mm thread with a focal length of over 50mm. It will also attach to lenses with 49mm and 52mm threads using the included adapters. A 62mm adapter is also sold separately. A general working distance of between 9 and 22cm is recommended for most non-macro lenses with macro lenses allowing closer focus.