t. Use the lead sheets to block off the surrounding regions.
u. Set the SID at 40 inches.
v. Set the control panel.
w. Make the exposure.
For three-phase machines, the mAs should be decreased by approximately
x. Process the film.
EVALUATION AND INTERPRETATION
a. Determine the "match" step in each region.
Use the densitometer.
(2) Find the point where the density in the left column most closely matches
the density in the right column.
b. Use the calibration chart provided by the manufacturer.
Read up the vertical axis of the chart to the appropriate step number.
(2) Draw a horizontal line from the appropriate step number. The line
intersects with the calibration curves on the chart.
There are two calibration curves. One is for a single phase, and the other is
for a three-phase machine.
Draw a vertical line.
Start the line from the point where the horizontal line intersects with
(b) Continue the line to the kVp readings at the bottom of the chart.
Compare the actual kVp reading with the indicated kVp reading.