Binzel Method - Reference Field

By measuring several stars in a reference field with known magnitudes in a given
filter, you can use this reduction method to find the average difference between the
measured instrumental magnitude and the catalog value. In a perfect world, this value
would be a constant since there should be a 1:1 magnitude correspondence, i.e., a star one
magnitude fainter in the catalog should have an instrumental magnitude that is exactly one
magnitude fainter. However, that requires that your system exactly match that of the
standard. This is not likely and is a good reason that you should use reference and
comparison stars that are similar in color to the target.
This reduction method computes the "Ref. Offset" shown in the Reductions
Values for above.