A neutral density filter darkens the light reaching your sensor by a set number of stops, which lets you use much longer shutter speeds in daylight for silky water, blurred clouds, and empty streets. Each stop of ND doubles the required exposure time, so the math grows fast. This calculator takes your base shutter speed without a filter and the strength of your ND filter and returns the correct new shutter speed. Choose a common filter such as a 6 stop or 10 stop, or type any number of stops, and it also accepts the ND number notation like ND1000. When the result runs past thirty seconds it reminds you to switch to bulb mode with a timer or remote. This removes the guesswork and the risk of a ruined long exposure. All the math happens in your browser, so nothing you enter is sent anywhere.
A neutral density filter darkens the light reaching your sensor by a set number of stops, which lets you use much longer shutter speeds in daylight for silky water, blurred clouds, and empty streets. Each stop of ND doubles the required exposure time, so the math grows fast.
Yes. ND Filter Calculator is completely free, with no sign-up and no usage limits.
Yes. ND Filter Calculator runs in any modern web browser. There is nothing to download or install.
Yes. ND Filter Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.