m. Subtract the speed-reading from the higher reading. The difference between
the two readings is the "contrast." For example, the density at step 9 is 1.82, and the
density at step 5 is 1.0. The difference is .82, which represents the contrast.
n. Plot this reading on the appropriate area of the chart.
o. Chart the temperature of the developer.
Section II. AUTOMATIC PROCESSOR ACCURACY TEST--DAILY MAINTENANCE
7-6.
PURPOSE
The automatic processor accuracy test - daily maintenance assures that the daily
operation of the processor is at an optimum level for consistent quality radiographs.
7-7.
EQUIPMENT
a. Sensitometer.
b. Densitometer.
c. Digital thermometer of metal stem.
d. Control film used for densitometer or sensitometer strip.
7-8.
PROCEDURE
a. Follow the start-up procedures recommended by the manufacturer.
b. Assure that the processor's chemicals are stabilized.
c. Run several clean up films through to check the processor's operation. Do
not use the control film.
d. Expose proper number of sensitometric strips. Expose only enough for one
day.
e. Wait at least 30 minutes (to stabilize) but no longer than four hours (so film
won't deteriorate).
7-9.
EVALUATION AND INTERPRETATION
a. Zero and calibrate the densitometer.
b. Read the sensitometric strips for speed, contrast, and base-to-fog using the
same step on the strip used in establishing the norms.
MD0062
7-9