Use this page to calculate the exposure difference in stops/EVs between two images by inputting the shutter speed, aperture, ISO and ND filter reduction (if any).
1/4000for 1/4000th of a second, or
30for 30 seconds.
8for F/8, or
3, or a 12-stop filter (AKA "ND4096") type
12. If no filter was used, leave it blank or type