B+W 72mm Circular Polarizer S03 Filter - Schott Glass - Brass Ring - 65-062161
- 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 distant landscapes and provides more saturated, vivid colors. Strongest effect when used at a 90 from the sun.
- Circular polarizers are ideal for use with digital cameras and autofocus lenses where a linear polarizer will often disrupt auto exposure and focus features. Features a single anti-reflection coating per side to help prevent ghosting and reflections as well as increase light transmission from approximately 92% (uncoated glass) to over 98%.
- Constructed from high quality Schott glass for optical clarity. Brass filter ring helps to prevent jamming and provides additional strength.
- Plastic case included for storage and transport.
TheB+W 72mm Circular Polarizer S03 Filteris a highly efficient standard circular polarizing filter for all cameras with beam splitters in the light paths of their TTL exposure meter and with autofocus lenses. Circular polarization has the same pictorial effect as linear polarization, but allows for proper exposure metering and/or autofocus distance settings. B+W Polarizers increase color saturation and reduce reflections. The neutral gray color and plane parallel polarizer material guarantee optimal image results. High-quality optical glass ensures excellent pictorial quality. The filter factor varies according to how the filter is positioned in relation to the sun. Exposure compensation is about two f-stops. Linear and circular polarizers both consist of a linear polarizer foil but differ in their construction in the following way. Modern DSLR cameras have a beam-splitting prism that sends part of the incoming light to the meter and part to the viewfinder. The effect is that the light entering the meter is partially polarized by the beam-splitter. A linear polarizer placed on the lens of such a system will act as a second polarizer and block light to the meter by a degree dependent on the angle between the prism and the polarizer on the lens. The result is incorrect exposure/aperture values from the meter. The circular polarizer circumvents this problem through the addition of a 1/4-wave retarder, or delay foil. This ensures that the linearly polarized light is changed into a rotation that appears unpolarized to the meter, resulting in proper exposure/aperture readings. The glass of this filter is uncoated. This is common with special effects filters, where coating is either an impossibility or would work against the effect the filter is trying to attain. B+W filters are constructed from high quality Schott glass for increased optical clarity and color fidelity.