The Tiffen ND3.0 10 Stop ND Filter is the ultimate filter for Landscape Photographers. This filter reduces the amount of light passing through the camera lens by approximately 10 stops without changing the color of the scene. They are especially useful in bright light conditions to help prevent overexposure. Neutral Density filters also allow proper exposure at a wider lens opening for reduced depth-of-field to highlight a key subject by making the foreground and/or background out of focus. Tiffen filters are manufactured using their award-winning ColorCore™ technology, a process that entails permanently laminating the filter material in between two pieces of optical glass that are ground flat to tolerances of a ten-thousandth of an inch, then mounting them in precision metal rings. This allows us to control the color and density of Tiffen filters, and the characteristics of special effects filters with much greater accuracy than typical dyed-in-the-mass filters, which usually exhibit color and density variations. All Tiffen filters carry a 10 year warranty.