Circular Polarizing Filter (CPL) for Nikon AF-S NIKKOR 20mm f/1.8G ED

Built with an ultra-slim aluminum frame to prevent vignetting while preserving smooth rotation for level adjustment. The nonslip upper rim provides a secure grip for easy installation, rotation and removal. Optical surfaces feature double-sided, multi-layered coatings that are anti-oil, anti-dust, anti-soil, scratch & water resistant. This circular polarizing (CPL) filter removes unwanted reflections from non-metallic surfaces such as water and glass, while enhancing color and contrast. Commonly used to increase saturation and contrast in blue skies and white clouds, it also reduces haze in distant landscapes to produce more vivid colors. The CPL functions by arranging and filtering directionally polarized light perpendicular to reflected light so much of the reflection is absorbed; the effect is strongest when the filter is used at a 90° angle from the sun.