ATW ND Filter Calculator

ATW ND Filter Calculator will assist you in determining the correct shutter speed when using photographic filters.
Be it an astronomical filter or your favorite neutral density filter, ATW ND Filter Calculator comes to the rescue.

Listening to the demands of many users, we developed a nifty, yet powerful tool:
- Select the shutter speed your camera indicates
- Select the type of filter
and the app will immediately display the required shutter speed.

ATW ND Filter Calculator gives you the opportunity to calculate up until 20 stops,
that's a filter factor of over 1 million!
Those stops are divided in steps of 1, 1/2, 1/3 or 1/4 stop.
Base shutter speeds are ranging from 1/16000 to 1 hour, calculated shutter speeds up to one month.

Are you stacking your filters?
With ATW ND Filter Calculator you can stack all the filters you want.

No need to remember your last used settings, the app will do that for you.

We've thrown in a night view mode, to preserve your night vision when you're active in astrophotography.

Last, but not least, ATW ND Filter Calculator offers you a timer mode, which will sound or vibrate after the calculated shutter speed expires.

Remember, ATW ND Filter Calculator is NOT an exposure calculator.
Your camera will tell you a certain exposure and the app will show you the corrected shutter speed using one or more specific filters.
No need to enter F/Stop or ISO, that's up to your camera.