Neutral Density Half-Frame Filter K&F KF01.1540 55mm ND8 (Gray) Optical Glass

K&F 55mm ND8 half-frame neutral density filter KF01.1540 is an optical glass graduated filter that reduces incoming light by three stops in the darkened portion of the frame. It fits lenses with a 55mm front thread and provides a smooth transition between the darkened and clear areas. The filter is intended to help control exposure differences within a single scene, for example reducing bright skies while preserving details in darker foregrounds, and to support longer shutter speeds for motion blur effects.

Advantages

The ND8 half-frame filter uses optical glass to maintain image sharpness and colour fidelity while introducing neutral light attenuation in the upper part of the image. Its graduated design enables controlled exposure blending without vignetting typical of full-frame filters on wide-angle lenses. The 55mm screw mount provides a secure attachment to compatible lenses and allows stacking with other 55mm threaded accessories when required. The neutral density effect corresponds to a three-stop reduction, giving predictable control over exposure and shutter speed adjustments.

Suitable for

• Landscape photography where bright skies need to be balanced with darker foregrounds
• Long-exposure photography to create motion blur in water, clouds or traffic
• High dynamic range scenes to reduce highlight clipping in a single exposure
• On-location shooting with 55mm-thread lenses and compact filter kits

Key specifications

• Filter type: graduated (half-frame) neutral density
• Material: optical glass
• Light reduction: 3 stops (ND8) in the darkened area
• Mount diameter: 55 mm screw thread
• Transition: gradual between dark and clear zones

How to use

Screw the filter onto the front thread of a lens with a 55mm diameter, ensuring the darkened portion is aligned with the bright area of the scene (typically the sky). Compose the shot and adjust focus with the filter in place. Meter exposure based on the combined effect of the filter and scene brightness or use exposure compensation/manual exposure to account for the three-stop reduction in the filtered area. For long-exposure effects, use a tripod and remote release to minimise camera movement.

Usage recommendations

Position the graduated edge to match the horizon or the boundary between bright and dark areas for a natural transition. For scenes with irregular horizons, consider tilting the filter slightly or using multiple exposures combined in post-processing. Avoid excessive rotation when stacking filters to prevent light leaks and ensure secure mounting to maintain alignment during shooting.