Ice 100 x 150mm Reverse-Graduated ND 0.9 Filter (3-Stop)

This Ice 100 x 150mm Reverse-Graduated ND 0.9 Filter is compatible with filter holders that can accommodate filters that are 100mm wide and 2mm thick. It can be applied to darken bright skies, specifically during a sunrise or sunset, while allowing for a normal, unaffected exposure in the other regions of the image.

This filter achieves its effect with a 0.9 band of density above its center region that provides up to a 3-stop reduction in light from entering a lens. This band extends in both vertical directions and tapers to approximately a 0.3 density and a 1-stop reduction in light at the edge above it. Directly below the 0.9 band of density, it tapers to clear, with a hard-edged line of transition before the clear area.

The placement of a 0.9 band of density with a clear area directly below allows the Ice 100 x 150mm Reverse-Graduated ND 0.9 Filter to match the positioning of the sun when it is at, or immediately above, the horizon. In such instances, the sun can appear closer to the center of an image as opposed to the upper edge, and an increase in brightness is created that is more prominent on both sides of the sun than above it. This pattern of brightness corresponds to the density pattern on the Ice 100 x 150mm Reverse-Graduated ND 0.9 Filter. The hard-edged line of transition in this reverse-graduated neutral density filter is useful for hard transitions between the sky and land, while the 3-stop to approximately 1-stop gradation is applicable to multiple regions of brightness within the sky.

This reverse-graduated ND filter is constructed from optical glass for clarity as well as color fidelity. A plastic case is included for storage and transport.