Vivitar NDX Filters, Adjustable From ND2 - ND1000...
• Vivitar Filters are manufactured from high-quality solid optical materials. Each individual filter is heat-treated to avoid any rare movement or distortion.
• This Variable Neutral Density filter reduces intensity of all wavelengths or colors of light equally, giving no changes in hue or color rendition.
• The purpose of standard photographic neutral density filters is to allow the photographer greater flexibility to change the aperture, exposure time and/or blur of subject in different situations and atmospheric conditions.
• Instead of reducing the aperture to limit light, the photographer can add a ND filter to limit light, and can then set the shutter speed according to the particular motion desired and the aperture set as needed.