a. Place the wire-mesh test tool pattern and the cassette to be tested on the
radiographic table with the long axis of the cassette perpendicular to the anode-cathode
axis of the x-ray tube.
b. Position the x-ray tube to the center of the cassette.
c. Adjust the focal film distance to 40 inches.
d. Collimate the x-ray beam to the cassette (see figure 9-3).
Figure 9-3. Wire mesh patterns that are interchangeable
for 8- x 10-, 10- x 12 and 11- x 14-inch cassettes.
e. Place the screen-film test pattern on the cassette.
If using paper clips, place the paper clips on the cassette front surface, evenly
distributed (see figure 9-4).
f. Use machine factors to produce optical density between 2.5 - 3.8 (60 kVp,
small focal spot and approximately 5 mAs) for the radiograph wire mesh.
g. Repeat the above procedure on all cassettes to be tested.