· When you need to balance the light in one part of a scene with another, the use of a graduated neutral density filter is essential. · Graduated neutral density filters are gray toned in one half of the filter and are smoothly graduated into the clear portion. · B&W Graduated Neutral Density filters are available in 2 grades; #501 Light (approx. 1 stop density) and #502 Dark (approx. 2 stops density).