Wide-angle zoom designed for FX-format sensors, this 16-35mm lens can also be used with DX models where it provides a 24-52.5mm equivalent focal length range.. Constant f/4 maximum aperture offers consistent performance and light transmission throughout the zoom range.. Three aspherical elements are used to reduce spherical aberrations and distortion in order to realize sharp imagery with accurate rendering.. Two extra-low dispersion elements greatly reduce color fringing and chromatic aberrations in order to produce greater clarity and color accuracy.. A Nano Crystal Coat has been applied to individual elements to suppress internal reflections, flare, and ghosting for improved contrast and color accuracy when working in strong lighting conditions.