Sunglasses for your camera lenses

Neutral density filters, also known as ND or gray filters, are darkened glass lenses used for the camera lens to reduce light intensity. The lenses are evenly grayed and, as a result, the light intensity that hits the sensor after passing through the filter and the lens is reduced. A gray filter allows you to choose opt for longer exposure times or a bigger camera aperture without affecting the color or the contrast. Gray filters are “sunglasses for camera lenses”.

A neutral density filter is essential if you’d like to create time exposures during the daytime. When you don’t use a filter, the light is too intense.

These filters are defined according to their optical density. The higher the optical density, the lower the transmission. They are also used to separate a subject matter from the background. In other words, the depth of field is reduced.

To name but a few examples, extremely intense image situations occur during welding processes, during laser applications, during the combustion process in e.g. engines, when viewing light sources and during melting processes in blast furnaces.

Mount & Size Options:

  • Threaded mount sizes: M22.5 to M105
  • C/CS mount, slip mount for lenses without filter threads, step-up/step-down adapter
  • Custom shapes and sizes; mounted and unmounted versions available

ND serie: VIS-area

Art. no.DescriptionTransmissionFilter curve


Neutral Density Filter - Absorptive 50% Transmission; optical density: 0.3425-675 nmCurve


Neutral Density Filter - Absorptive 25% Transmission; optical density: 0.6425-675 nmCurve


Neutral Density Filter - Absorptive 12.5% Transmission; optical density: 0.9425-675 nmCurve


Neutral Density Filter - Absorptive 6.25% Transmission; optical density: 1.2425-675 nmCurve


Neutral Density Filter - Absorptive 1.0% Transmission; optical density: 2.0425-675 nmCurve


Neutral Density Filter - Absorptive 0.1% Transmission; optical density: 3.0425-675 nmCurve


Neutral Density Filter - Absorptive 0.01% Transmission; optical density: 4.0425-675 nmCurve


Ni-series: VIS/NIR area

Art. no.DescriptionTransmissionFilter curve


Neutral Density Filter - Low Reflectivity 50% Transmission; optical density: 0.3400-1100 nmCurve


Neutral Density Filter - Low Reflectivity 25% Transmission; optical density: 0.6400-1100nmCurve


Neutral Density Filter - Low Reflectivity 12.5% Transmission; optical density: 0.9400-1100nmCurve


Neutral Density Filter - Low Reflectivity 6.25% Transmission; optical density: 1.2400-1100nmCurve


Neutral Density Filter – Reflectivity 1% Transmission; optical density: 2400-2000 nmCurve


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