The Tiffen 6.6 x 6.6" 3 Straw Hard-Edge Graduated Filter helps to specifically add a warm, golden yellow coloration to skies and other bright areas of an image while allowing a portion of the image to remain neutrally colored. The filter's coloring is densest at the edge and tapers to clear by the middle, with a hard-edged transition between the density and clear areas. The 3 color density provides more straw coloration than the 2 density filter.