The 72mm alpha II Circular Polarizer Filter from Hoya has a slimmer frame and better glass than the original alpha CPL. Leaving out premium features like multi-coating, optical glass, and a hardened, waterproof top layer, the alpha series is designed as an entry-level CPL filter for those starting out in photography.
The alpha II CPL gives scenic photography more punch by darkening blue skies so that white clouds and foliage stand out. Light rays become polarized when traveling through moisture and pollution, as well as when they reflect off non-metallic surfaces such as glass or bodies of water. A polarizing filter absorbs polarized light and helps remove unwanted reflections from non-metallic surfaces. By removing these reflections, this filter also increases color saturation, especially in leaves and foliage.