NUANCES C-PL are manufactured in a mineral Hi-resolution Glass Schott B270i and absorb 1 f.stop of light. In sunny weather – and even more during morning or evening hours – and if you respect a right angle (90°) between the shooting axis and the position of the sun, a polarizing filter will darken the blue of the sky throwing the clouds into stark relief. Polarizing filters significantly improve the saturation of colors. You will obtain greener greens, richer reds and ever more brilliant yellows. You will be surprised to see how certain colors, dull to the naked eye, become vibrant and dazzling with this filter. In all kinds of weather, polarizing filters reduce, eliminate, and deepen reflections on all non-metallic surfaces like water or windows. It brings transcendence to vegetation, transforms bodies of water, opens vistas. Note that with wide-angle lenses from 24mm and shorter (in 35mm photography terms) the side of the image which is farthest from the sun will be darker than the other. This is an inevitable optical phenomenon, independent of the polarizing filter.