What Does ND Stand for in Photography?

ND stands for neutral density and is used to describe a type of photographic filter that diminishes the amount of light transmission through a lens.  A neutral density filter is designed to be as close to color-neutral as possible, so the only effect that it should have is to cut down the amount of light that is hitting your camera’s sensor or film.

You might want to do this in order be able to use a wider aperture on a sunny day, to maintain a shallow depth of field, or you might do it to allow you to increase your shutter speed in order to blur clouds or moving water in a landscape photo.

For more details on neutral density filers, please see the entry “What is a neutral density filter in photography”.

Additional Reading

 

Neutral Density Filter Reference Table

F-Stop ReductionOptical DensityFilter Factor% transmittance
000100
10.3250
20.6425
30.9812.5
41.2166.25
51.5323.125
61.8641.5625
72.11280.78125
82.42560.390625
92.75120.1953125
103.01024 (sometimes called ND1000)0.09765625
113.320480.048828125
123.640960.0244140625
133.981920.01220703125
13 1/34.0100000.01
144.2163840.006103515625
154.5327680.003051757813
164.8655360.001525878906
16 2/35.01000000.001
175.11310720.0007629394531
185.42621440.0003814697266
195.75242880.0001907348633
20610485760.00009536743164

 

FREE Download – Long Exposure Chart PDF

long exposure charts

Lots of people rely on mobile apps these days to help them calculate their long exposure values, but this can be problematic in cold weather which can often cause mobile device batteries to shut down prematurely.  For this reason, I always recommend that you have a printed long exposure chart tucked away somewhere in your camera bag. This free downloadable long exposure chart PDF is split up into several sections so that you can print the ones that are relevant to you and your selection of ND filters.  You can either choose to have the full table with all ND values, or choose pages that only show specific, common ND filter sets used by many landscape photographers.

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