The Circular Polarizing F-Pro filter reduces and can eliminate reflections on glass, plastic and water surfaces. Polarizing filters give you the control over how much reflection you wish to remain because the light reflected at an angle of about 40° to 70° by these surfaces is strongly polarized. Its transmission can be reduces, blocked or even enhanced in relation to the remaining un-polarized light, depending on the rotation of the filter.
The standard filter mount F-Pro can be used on most wide-angle lenses without the danger of vignetting. As a guide this filter mount can be used without vignetting on 35mm camera lenses (approx 63° diagonal angle of view). Also, most wide-angle lenses with 28mm (approx 75° angle of view) and in many cases even with 24mm (approx 84° angle of view) can be combined with the F-Pro mount without the risk of vignetting. Another advantage of the new F-Pro filter mount is that the glass is no longer held in place from the front, but from the back by the retaining ring. This prevents the retaining ring from being accidentally loosened during the removal of an additional filter or a lens hood which has been screwed in too tightly.