Understanding Neutron Radiography Reading V-Kodak Part 2 of 3

■ Example 2: Film X has a higher contrast at D = 2.0 than Film Z and also
has a finer grain. Suppose that, for these reasons, it is desired to make the
aforementioned radiograph on Film X with a density of 2.0 in the same region
of maximum interest. Superimpose the overlay on the characteristic curve so
that the horizontal line coincides with the horizontal line for a density of 2.0,
and position the overlay from left to right so that the curve for Film Z cuts the
line at the original exposure of 50 mA-min (Point C in Figure 52). Read the
new exposure of 97.5 mA-min at the point at which the curve for Film X cuts
the horizontal line (Point D in Figure 52).
Charlie Chong/ Fion Zhang
Radiography in Modern Industry. Rochester, NY: Eastman Kodak Co. 1980