The round polarizing filter has been specifically designed for autofocus DSLR cameras and provides the same effects as the elongated polarizing filter. The COKIN round polarizing filter gives colors an ideal saturation, enhances contrasts, and imparts the sky with its characteristic blue hue. Additionally, the filter features a neutral density that reduces light by 2 stops. The COKIN round polarizing filter is surrounded by a notched ring and is inserted into the first guide slot of the COKIN filter holder, allowing it to be rotated. Depending on its position, it reduces or eliminates reflections on water, glass, painted and lacquered surfaces, stones, and other surfaces, except for metallic surfaces and mirrors. By checking your image settings in the viewfinder and rotating the filter, you will better appreciate the benefits of a photo without distracting reflections. The sky becomes bluer, the background clearer, shop windows more transparent, and objects stand out with even more relief.