If you are ever planning to shoot photography outside — whether it be a vibrant cityscape or gorgeous landscape — you will want to use a neutral density filter (or ND filter). An ND filter essentially blocks light coming into the lens without altering any colors you’re seeing (hence the “neutral” part of the name). Some newer photographers are not sure when to use an ND filter since it’s often said that light is good to have….

Check out the original article: [Slashgear]What Are ND Camera Filters?