Helping to balance the overall exposure within a high-contrast scene, this Graduated ND Filter from Cavision neutralizes the exposure between a dark foreground and a bright sky. Half of this filter has a three-stop, 0.9 neutral density area and the other half is clear, with a medium-soft-edged transition between the two for a natural appearance when photographing uneven or undulating horizon lines. By reducing the exposure in selective areas, you can balance the overall exposure of the scene in order to gain detail in both bright and dark areas.