With the Hoya PL-CIR SLIM polarization filter, you increase the contrast and the color intensity of your photos. The filter also counters glare and reflections. Using this filter, you can photograph the surface of the water and also experience depth. You can't do that without a polarization filter, because the water's reflection blocks your view. By turning the front ring, you can determine the desired effect. Because the Hoya PL-CIR SLIM has a slim rim, you can also use it on wide-angle lenses without the filter's rim ending up in the image.