The Hoya 49mm alpha Circular Polarizer Filter helps to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface. The light from the sun naturally becomes partially polarized due to reflecting off electrons in air molecules, causing the light to scatter into what appears as haze. A polarizing filter arranges and filters, this directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of this light. This results in a noticeable reduction of glare and reflections from non-metallic surfaces and an increase in the saturation of skies and foliage. A circular polarizer only differs from a linear polarizer in that it contains a quarter wave plane in addition to the linear polarizing filter. The addition of this quarter wave plane is to circularly polarize the linearly polarized light for the use of auto focus and exposure functions. Due to how the light is broken down and filtered with a linear polarizer, auto focus and exposure accuracy become skewed during use. When the light becomes circularly polarized, it permits the use of these functions. Helps to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface. Polarizing filters arrange and filter, directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of the light. Clears up haze in dista

Package Weight: 0.023 kg. Package Quantity: 1. Product Type: Camera Lens Filters. Package Dimensions: 1.524 cms (L) x 7.112 cms (W) x 1.524 cms (H).

Water Resistance Level: Not Water Resistant. Photo Filter Effect Type: Polarizer. Coating Description: Multi Coating. Photo Filter Thread Size: 49 Millimeters. Material: Plastic. Brand: Hoya. Manufacturer: Hoya. Date First Available: September 28, 2012. Is Discontinued By Manufacturer: No. Best Sellers Rank: #35 in Camera Lens Polarizing Filters. Customer Reviews: 4.5 out of 5 stars 102 ratings 4.5 out of 5 stars. Item model number: ALP49CRPL. : B009IV32AM. Item Weight: 0.8 ounces. Product Dimensions: 1.5 x 1.5 x 0.3 inches.