The FotodioX 186mm Slim Circular Polarizer Filter is compatible with FotodioX WonderPana FreeArc XL holder systems. It helps to reduce reflections as well as 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.
The FotodioX 186mm Slim Circular Polarizer Filter is constructed from optical glass for clarity as well as color fidelity and features lightweight, slim, aluminum-alloy filter rings. A rear filter ring connects to a compatible filter holder while the front filter ring allows the filter glass to be easily rotated. This provides the ability to achieve the desired degree of polarization.
A separately-available FotodioX 186mm Center-Pinch Snap-On Lens Cap can be used to protect the front of a FotodioX 186mm Slim Circular Polarizer Filter that is placed in front of a lens.