The Heliopan 72mm 0.6 Neutral Density 4x Filter is an important tool for controlling light. This filter allows for the creative use of less depth of field under bright lighting, since the aperture has to be larger. In addition, long time exposures are possible with stronger ND filters in sunlight. With digital imaging over exposure can be avoided resulting in natural color reproduction. Heliopan ND gray filters are manufactured from color neutral Schott glass so they can be used for color imaging. The ND .3 filter has a filter factor of 4x.