Nikon BC-7 Instructions Manual page 16

1 6
HOW TO USE THE EXPOSURE CALCULATOR
The calculator provided on the flash unit BC-7 is primarily designed
to facilitate the use of a flash bulb for foca l-plane shutter.
Set the film speed (ASA) graduated on the upper revolving dial to
the shutter speed graduated on the inside fixed dial, and the correct
exposure will be obtained by reading the lens aperture on t he fixed
dial or the subject distance on the revolving dial, either being brought
into coincidence with each other.