K&F ND32&PL, lens HD, one side coated with anti-reflection green film, waterproof and anti-scratch,

Neutral density filter, takes light away so you can lengthen the exposure or open the aperture.

• 28 anti-reflective layers
• The surface repels water and grease and resists scratches

A neutral density filter takes light away without touching the colours. In daylight it lets you shoot wide open with a blurred background, film at 1/50 s by the cine rule, or lengthen the exposure until water melts into mist and people vanish from the frame.

The surface repels water and grease, so drops run off and fingerprints wipe away without smears; the coating also stands up to cleaning in the field.

The filter is made to fit DJI Mini 4 Pro; it will not fit another device.

The glass does two jobs at once: it takes five stops like an ND32 and polarises at the same time, so the reflection off water or a wet road disappears and the sky darkens. Two pieces of glass in a row are no longer needed and only one layer sits in front of the lens.

The frames are kept light, so a fitted filter does not throw the gimbal out of calibration and the flight stays steady.