Use this app with any spot meter that reads EV. Enter the EV from the meter,
set the Zone you wish to place the reading in. Adjust the ISO, and Aperture and
the shutter speed will be displayed, as simple as that.
Since large format shutters have full stop shutter speeds, the aperture will
need to be adjusted sometimes. The Adjustment button shows how much adjustment
is needed. You can click on the button and the aperture will be adjusted for
you, ot you can do a manual adjustment. Give it a try, it is fun!