The Manfrotto Professional Circular Polarising filter 77mm improves the overall image quality in a couple of ways. Firstly it increases colour contrast and saturation, for instance increases the contrast of blue skies. Secondly, it reduces reflections that are often seen when photographing water, glass and similar reflective surfaces. Manfrotto Professional Circular Polarising filter ensures uniform light distribution; therefore maintain the sharpness and colour balance in images. The Professional CPL filter is water repellent, scratch and oil resistant and has a unique antistatic coating. It includes 12 layers of coating and allows 90% light transmission.