Circular Polarizing (CPL) Filter — Compatible with Sigma 18-200mm f/3.5-6.3 DC K

Compatible with Sigma 18-200mm f/3.5-6.3 DC K lenses, this Circular Polarizing (CPL) filter is built to improve color, contrast and clarity in outdoor photography. The ultra-slim aluminum frame avoids vignetting while maintaining rotation capabilities for adjusting levels, and a nonslip upper rim helps install, rotate and remove easily. It incorporates double sided, multi-layered coatings, anti-oil, anti-dust, anti-soil, scratch & water resistant for durable, reliable performance. Circular CPL filters allow you to remove unwanted reflections from non-metallic surfaces such as water, glass, etc., and can also enhance color and contrast — often used to boost saturation in blue skies and white clouds. CPL filters arrange and filter directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of the light. The result is reduced haze in distant landscapes and richer, more vivid colors, with the strongest effect achieved when shooting at a 90° angle from the sun.