K&F 49mm Ultra-Low Reflection Variable ND Lens Filter, ND2-400

Nano-X — variable ND filter 49 mm, changes the amount of light steplessly as you turn it.

• 28 anti-reflective layers, reflectance 0.1 %
• Screws onto a lens with a 49 mm thread.
• The surface repels water and grease and resists scratches

A variable ND replaces a whole set of fixed grey filters — turning the front ring changes how much light gets through, steplessly. While filming the shutter stays at 1/50 s even as the sun goes behind a cloud and comes back, with no need to stop the take or swap a filter.

The glass carries 28 anti-reflective layers and reflects only 0.1 % of the light, so no ghosting or veiling appears against the light.

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.