Neutral Density filters have several uses and offer the possibility of achieving otherwise impossible results. ND filters appear gray and reduce the amount of light reaching the film. ND filters also do not have an effect on color balance.
This ND filter reduce the amount of light entering the lens so wider apertures can be selected, which is perfect for portraiture to reduce depth of field.And this make your camera can be used in conditions of extreme light intensity. Subject appears crisp and clear while the background becomes a soft blur. Its also widely used for photographs of waterfalls and other nature scenes to emphasize movement for it enables the slower shutter speedto be used.