Tamrons sp af17 50mm f28 xr di ii vc ld aspherical if is a high speed wide to moderate telephoto zoom lens designed for nikon dslr cameras with smaller sensors it covers the very popular 17 50mm focal length range equivalent to 26 78mm in the full frame 35mm format making it extremely versatile tamrons vibration compensation vc mechanism minimizes the effects of handheld camera shake up to 4 stops providing a means to great low light shooting the lens delivers impressive sharpn