Accessories-Filters
Nikon filters are made of optical glass, ground and polished so that both surfaces are optically flat and parallel.
Nikkor lenses and Nikon filters are made for each other. For best results, use Nikon filters on Nikkor lenses. Nikon filters are available in both
Since filters cut down on the light passing through the lens, some increase in exposure time or in lens opening is necessary to compensate for the loss of light. This increase is expressed as a filter factor. For example, if the filter factor is 2, double the exposure time or open up the lens one full stop. Filter factors depend on the light source and type of film. The chart at right shows the filter factors.
No exposure compensation is necessary with the Photomic FTN finder. The
Color film
Type
Light
Yellow Medium
Deep
Orange
Red
Green 
Light Deep
Ultraviolet
Polarizing
Neutral Density
Skylight
Amber 
Light Deep
Light
Amber Medium
Deep
Designation
Y44
Y48
Y52
O56
R60
X0
X1
L37
L39
Polar
ND 4X
ND 8X
ND 100X
ND 400X
L1A
A2
A12
B2
B8
B12
Esposure factor
Daylight |
| Tungsten |
|
|
| ||
| light |
| |
|
|
| |
|
|
|
|
1.51
1.71.2
2 | 1.4 |
|
|
3.5 | 2 |
|
|
6 | 5 |
|
|
2 | 1.7 |
5 | 3.5 |
|
|
1
2.4
4
8
10
400
1
1.2
2
1.2
1.6
2.2