Circular Polarizer (CPL) for Pentax-D FA 645 55mm f/2.8 AL[IF] SDM AW Lens — Ultra-Slim Aluminum Frame

Designed for the Pentax-D FA 645 55mm f/2.8 AL[IF] SDM AW lens, this circular polarizing (CPL) filter reduces glare and boosts color and contrast. Its ultra-slim aluminum frame prevents vignetting while preserving full rotation to set the polarization level, and a nonslip upper rim makes mounting, turning and removal simple. The glass features double sided, multi-layered coatings and is anti-oil, anti-dust, anti-soil, scratch & water resistant. Use the CPL to cut reflections from non‑metallic surfaces like water and glass, deepen blue skies and white clouds, and clear atmospheric haze in distant landscapes. The filter works by arranging and filtering directionally polarized light perpendicular to reflected light, absorbing much of the unwanted reflection — with the strongest effect when the subject is about 90° from the sun.