Screen Shot--Windows Version of Filter Factor Calculator
This software is offered "as is" for you to try at your own risk.
The calculator will calculate the increase in f/stops needed for up to three filters. Most people seldom ever use two filters at the same time much less three unless a situation calls for stacking neutral density filters. The f/stop adjustment expressed in fractions is rounded to the nearest 1/4 f/stop.
I think most experienced photographers think of exposure as a range of possible f/stop and shutter speed combinations rather than just the one f/stop and shutter speed that might be indicated by your camera or light meter. So, in addition to showing how to adjust f/stops for filter use this might help new photographers that are not used to thinking in f/stops.
The OS X version of this calculator has not been tested on Intel chip versions but works fine on my Mac. Download is about 1 MB.
The Windows version will hopefully work OK, but I haven't had time to test it. I doubt it will work on Vista.
Mac OS X Download
Windows Download
