Variable ND Filter

The Lindsey Optics Brilliant 4 x 5.65″/138mm 1-Slot Variable Neutral Density Filter delivers smooth, adjustable light reduction in a single matte box stage. Designed to fit most 4 x 5.65″ matte boxes, it provides precise exposure control from 2 to 8 stops while maintaining excellent optical performance for professional cinema productions.

Variable Light Reduction

The filter offers adjustable neutral density from ND 0.6 (2 stops) to ND 2.4 (8 stops), allowing you to control exposure without changing filters. The calibrated thumb wheel uses reduction gearing, where one full 360° rotation produces 90° rotation of the main gear, providing approximate stop markings between 2 and 8 stops.

Fits in a Single Matte Box Stage

The Brilliant filter features a unique tray mount design that installs quickly into most 4 x 5.65″ matte boxes while occupying only one filter slot. Its 6mm thickness allows seamless integration into professional cinema workflows.

Built to Prevent Unwanted Polarization

The Variable ND uses two Lindsey Optics 138mm Brilliant Pol circular polarizers, with one rotating and one fixed. The quarter-wave retarders face outward to depolarize light on both sides of the filter. This design prevents accidental polarization in the scene and avoids cross polarization inside the camera and lens system. The filter can also be inserted into the matte box in either orientation.

Premium Optical Glass

The filter uses Schott B270 water white optical glass with a broadband multi-layer anti-reflection coating. This construction reduces flare, ghosting, stray light, and internal reflections while improving contrast and color saturation. The glass is ground and polished to remain exceptionally flat, preventing distortion and focus shifts, even when using long focal length lenses.

Large Clear Aperture

The integrated 138mm circular polarizers provide a large 5.1-inch clear aperture that supports wide-angle lenses and large zoom lenses without restricting the image.

Smooth Manual or Motorized Operation

You can adjust density manually using either thumb wheel or attach a motor using the integrated 1/4″-20 threaded handle. The all-aluminum main gear rides on Delrin™ rollers for smooth, slip-free rotation, while the 0.8 pitch gear teeth support motorized wireless remote systems. Synchronizing the motor with the lens aperture also enables creative variable depth-of-field effects.

Compatible with Lindsey Optics RotaPol

The Variable ND works together with the Lindsey Optics RotaPol Circular Polarizer when the RotaPol is positioned in front of the Variable ND. This setup allows independent motorized control of both polarization and neutral density using a wireless FIZ system.

Key Features

• Fits most 4 x 5.65″ matte boxes using a single filter stage
• Provides adjustable ND 0.6 to ND 2.4 (2 to 8 stops)
• Calibrated thumb wheel with reduction gearing for precise adjustment
• Constructed with two 138mm Brilliant Pol circular polarizers
• Prevents accidental scene polarization and internal camera cross polarization
• Schott B270 water white optical glass with multi-layer anti-reflection coating
• Large 5.1-inch clear aperture supports wide-angle and zoom lenses
• Supports manual or motorized operation with 0.8 pitch gears and 1/4″-20 motor mount