K&F Adjustable Neutral Density Filter ND3–ND1000, 37 mm (KF01.2054)

The K&F Adjustable Neutral Density Filter ND3–ND1000, 37 mm is a variable-density optical filter designed to control light entering the lens. It fits lenses with a 37 mm front thread and provides smooth, continuous attenuation from approximately ND3 to ND1000. The filter lets photographers and videographers reduce exposure without changing aperture or shutter speed settings, enabling longer shutter speeds, motion blur effects, and wider apertures in bright conditions.

Advantages

The adjustable ND design replaces multiple fixed-density filters by offering a continuous range of light reduction, simplifying kit composition and on-location adjustments. Machined circular filter frame ensures reliable mounting on compatible 37 mm threads, while multi-coated optical glass reduces reflections and preserves color neutrality. The compact, lightweight construction makes it suitable for travel and handheld shooting, and the variable attenuation allows precise control over exposure and depth-of-field effects.

Suitable for

• Landscape photography requiring long exposures to smooth water and cloud movement
• Portraits or video where wider apertures are needed in bright light
• Motion blur techniques for subjects such as waterfalls, traffic, or moving crowds
• Time-lapse and cinematic video to control shutter angle and frame exposure

Key specifications

• Filter type: adjustable (variable) neutral density
• Light attenuation range: approximately ND3 to ND1000
• Mount size: 37 mm screw thread for front of lens
• Optical material: multi-coated glass (anti-reflection coatings)
• Construction: circular metal frame compatible with 37 mm lens threads
• Weight and dimensions: compact, lightweight design suitable for travel and handheld use

How to use

Screw the filter onto the lens front with the camera turned off or lens cap on to avoid accidental contact with the sensor or mirror. Rotate the adjustable ring to set the desired level of attenuation while observing the exposure indicators in the viewfinder or on the screen; small rotations produce smooth changes in density. When using very long exposures or strong attenuation, use a tripod to avoid camera shake and review histogram or exposure preview to confirm correct exposure. Remove or cover the filter when not needed to prevent additional reflections or vignetting on wide-angle lenses.

Usage recommendations

For best results, combine the filter with a tripod and remote release when creating long exposures. Verify that the chosen attenuation does not introduce color cast by checking white balance in-camera or in RAW processing. On wide-angle lenses, watch for potential vignetting at maximum density and adjust composition or reduce density if necessary.