Sirui 100 x 150 mm 4-stop reverse GND filter

100 × 150 mm Reverse GND Filter

The Sirui rectangular graduated neutral-density filter measures 100 by 150 mm and delivers a 4-stop reverse transition. It is built for landscape and seascape photographers who need balanced exposure when the brightest band of light sits at the horizon during sunrise or sunset. The 2 mm thick Schott B270 glass is precision-ground and polished for optical flatness, then coated with multiple nano layers to suppress reflections and glare.

Four-Stop Light Reduction and Horizon Control

The 4-stop density smoothly darkens the sky while leaving the foreground untouched, handling the extreme contrast typical of dawn and dusk. Because the transition is reversed, the densest portion aligns with the horizon line rather than the top of the frame, so the filter runs out of usefulness when the brightest area moves far above or below that line. It is not suited for scenes where the transition zone must fall in the upper third of the composition.

2 mm Schott Glass and 100 mm Holder Compatibility

The filter fits Sirui’s NDH-001 holder and other standard 100 mm systems, accepting lenses as wide as 16 mm on full-frame bodies with filter threads up to 82 mm without vignetting. The hardened 2 mm substrate resists scratches in the field, while the nano coating repels water and oil for easier cleaning. Photographers using filter threads larger than 82 mm or holders narrower than 100 mm will need a different solution.