The Hoya 67mm Polariser Filter means that you can significantly reduce reflections & glare from non-metallic surfaces. A camera angle of 30 degrees from the reflecting surface (glass, water, etc.) is ideal for maximum effect. The Polariser Filter also enables colours to become more saturated & appear clearer with better contrast. This effect is often used to increase the contrast & saturation in blue skies & white clouds. Hoya's polarising filters do not affect the overall colour balance of a shot. Please note: this is a linear polariser & therefore not suitable for Auto Focus cameras. For these you require a circular polariser.