Haida 100 x 150mm Red Diamond Hard-Edge Reverse-Graduated Neutral Density 0.9 to 0.3 Filter (3- to 1-Stop)

This 100 x 150mm Red Diamond Hard-Edge Reverse-Graduated Neutral Density 0.9 to 0.3 Filter from Haida is compatible with the Haida 100 or 100-Pro Filter Holder. 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 across its center region that provides a 3-stop reduction in light from entering a lens. This band extends approximately 15mm in both vertical directions. With a soft-edged line of transition, it tapers to a 0.3 density that provides 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 that tapers to a density of 0.3 above it with a clear area directly below, allows the Haida 100 x 150mm Red Diamond Hard-Edge Reverse-Graduated Neutral Density 0.9 to 0.3 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 Haida 100 x 150mm Red Diamond Hard-Edge Reverse-Graduated Neutral Density 0.9 to 0.3 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 1-stop gradation with a soft-edged line of transition is applicable to multiple regions of brightness within the sky.

Haida Red Diamond filters are constructed from shock-resistant optical glass. To prevent internal ghosting and reflections, while further enhancing clarity and color fidelity, each glass surface includes 10 layers of anti-reflective nano coatings. An additional 10 scratch-resistant hydrophobic coatings further protect the filter's substrate and result in an improved beading effect when its surfaces come in contact with water or oil, allowing for more efficient cleaning. Additionally, Haida Red Diamond filters feature rounded edges for easier placement within a compatible filter holder slot.

A metallic case for storage and transport is included, as well as a light-blocking gasket. This gasket forms a seal that is intended to prevent stray light, which could have unwanted effects on exposure, from coming in between the filter and the lens behind it.