ND Filter Exposure Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 27, 2026ND Filter Exposure Calculator
Adding a neutral density filter for long-exposure photography? This calculator converts your base exposure into the correct new shutter speed.
New Shutter Speed = Base Shutter Speed x 2^(ND Filter Stops)
Example
Base exposure of 1/60 sec, using a 10-stop ND filter:
New Shutter Speed = 0.0167 x 2^10 = ~17.1 seconds
Why Each Stop Doubles Exposure Time
Each additional stop of neutral density blocks half the remaining light, requiring exactly double the exposure time to compensate - a 10-stop filter (commonly labeled "ND1000" or "ND1.0") requires 2^10 = 1024 times longer exposure than the unfiltered reading.
Common Use: Smoothing Water and Clouds
Strong ND filters (typically 6-10 stops) are popular for daytime long-exposure photography of moving water or clouds, since they allow shutter speeds of several seconds or more even in bright daylight, which would otherwise require an impossibly small aperture or impossibly low ISO.