This B+W F-Pro Circular Polariser MRC Filter reduces reflections of non-metallic surfaces and increases colour saturation and contrast. The neutral grey colour and plane parallel polariser material guarantee optimal image results. High-quality optical glass ensures excellent image quality. The filter light-loss factor varies according to how the filter is positioned in relation to the sun. Filter factor is between 2.3 and 2.8.
The MRC Multi-Resistant Coating by B+W is not only an extraordinarily effective multiple layer coating, it is also harder than glass, so that it protects filters from scratches (for instance when cleaning the filters), and it is also water and dirt repellent, thus facilitating filter maintenance.
This filter uses the standard B+W F-Pro filter mount, which has a front accessory thread and is made of brass. The F-Pro mount can be used with wide angle lenses, including most 24mm focal lengths on a full frame body, without vignetting. Another advantage of the F-Pro mount is it's modified retaining ring, which is no longer threaded in from the front, but holds the filter glass in place from the back. When removing a filter or lens hood that has been screwed on too tight to the filter, the retaining ring is not at risk of loosening.