ND Filter Calculator - Available on the Download Page
05th April 2012
This table works for all ND filters. ISO is not a factor.
Example 1
Set your preferred aperture and meter the scene. [f11]
Note the shutter speed required. [1/160th]
Read the Exposure Value [EV] for 1/160th at f11 [EV14.3].
Read up the f11 column
A 10 stop ND filter would be 14.3-10=EV4.3
Read across from 4.3 to get the shutter speed of 6 seconds
or
A 4 stop ND filter would be 14.3-4=EV10.3
Read across from 10.3 to get the shutter speed of 1/10 of a second
Switch to Manual mode on the camera and fit the ND filter
Shoot at the required settings
Example 2
Set your preferred aperture and meter the scene. [f4]
Note the shutter speed required. [1/6th]
Read the Exposure Value [EV] for 1/6th at f4 [EV6.7].
Read up the f4 column
A 10 stop ND filter would be 6.7-10=EV-3.3
Read across from -3.3 to get the shutter speed of 166 secs [2min 46sec]
or
A 4 stop ND filter would be 6.7-4=EV2.7
Read across from 2.7 to get the shutter speed of 2.5 seconds
Switch to Manual mode on the camera and fit the ND filter
Shoot at the required settings
Example 1
Set your preferred aperture and meter the scene. [f11]
Note the shutter speed required. [1/160th]
Read the Exposure Value [EV] for 1/160th at f11 [EV14.3].
Read up the f11 column
A 10 stop ND filter would be 14.3-10=EV4.3
Read across from 4.3 to get the shutter speed of 6 seconds
or
A 4 stop ND filter would be 14.3-4=EV10.3
Read across from 10.3 to get the shutter speed of 1/10 of a second
Switch to Manual mode on the camera and fit the ND filter
Shoot at the required settings
Example 2
Set your preferred aperture and meter the scene. [f4]
Note the shutter speed required. [1/6th]
Read the Exposure Value [EV] for 1/6th at f4 [EV6.7].
Read up the f4 column
A 10 stop ND filter would be 6.7-10=EV-3.3
Read across from -3.3 to get the shutter speed of 166 secs [2min 46sec]
or
A 4 stop ND filter would be 6.7-4=EV2.7
Read across from 2.7 to get the shutter speed of 2.5 seconds
Switch to Manual mode on the camera and fit the ND filter
Shoot at the required settings
