Neutral Density
In photography and optics, a neutral density filter or ND filter is a filter that reduces or modifies the intensity of all wavelengths or colors of light equally, giving no changes in hue of color rendition. It can be a colorless (clear) or grey filter. The purpose of a standard photographic neutral density filter is to reduce the amount of light entering the lens. Doing so allows the photographer to select combinations of aperture, exposure time and sensor sensitivity which would otherwise produce overexposed pictures. This is done to achieve effects such as a shallower depth of field and/or motion blur of a subject in a wider range of situations and atmospheric conditions.
|
ND1number
|
ND.number
|
NDnumber
|
Optical density
|
f-stop
|
% transmittance
|
|
ND 101
|
ND 0.3
|
ND2
|
0.3
|
1
|
50 %
|
|
ND 102
|
ND 0.6
|
ND4
|
0.6
|
2
|
25 %
|
|
ND 103
|
ND 0.9
|
ND8
|
0.9
|
3
|
12.5 %
|
|
ND 104
|
ND 1.2
|
ND16
|
1.2
|
4
|
6.25 %
|
|
ND 105
|
ND 1.5
|
ND32
|
1.5
|
5
|
3.125 %
|
|
ND 106
|
ND 1.8
|
ND64
|
1.8
|
6
|
1.563 %
|
|
ND 107
|
ND 2.1
|
ND128
|
2.1
|
7
|
0.781 %
|
|
ND 108
|
ND 2.4
|
ND256
|
2.4
|
8
|
0.391 %
|
|
|
|
ND400
|
2.6
|
8 2/3
|
0.25 %
|
|
ND 109
|
ND 2.7
|
ND512
|
2.7
|
9
|
0.195 %
|
|
ND 110
|
ND 3.0
|
ND1024 (also calledND1000)
|
3
|
10
|
0.098 %
|
|
ND 111
|
ND 3.3
|
ND2048
|
3.3
|
11
|
0.049 %
|
|
ND 112
|
ND 3.6
|
ND4096
|
3.6
|
12
|
0.024 %
|
|
ND 113
|
ND 3.9
|
ND8192
|
3.9
|
13
|
0.012 %
|
