ND : Only acts to attenuate the light, but it does not have any effect on the color of the original object, so the contrast of the scene can be reproduced realistically.

CPL : Is great for removing unwanted reflections from non-metallic surfaces such as glass or water.

Graduated ND : Half color, half clear with a graduated density transition for a smooth blending of color

Red filters: The red filter is for color correction in blue or tropical water at the depth of 12 to 75 feet.

Purple filters: The magenta filter helps color correct in freshwater lakes and reservoirs that appears green at depth of 12 to 75 feet.