AGFA Drystar 5500, Reference Manual

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152
2900H EN 20071108 Advanced operation (Key-operator mode)
D
RYSTAR
5500/5503 R
EFERENCE MANUAL
Performing the Annual QC tests for general radiography applications
(DT 2 B and DT 2 C)
Geometric Consistency Test
To be able to notice fluctuations in image size and aspect ratio, you must
perform this procedure once a year.
1
First, perform the daily test.
2
Measure the distances A and B of the geometric square on the QC general
radiography test image. Refer to ‘Establishing the image geometry reference
values for general radiography applications (DT 2 B and DT 2 C)’ on page 146 .
3
Record these values as measured distances A and B on Chart 4 (‘Drystar 5500/
5503 Geometric Consistency Control Chart’). Refer to
‘Charts for general
radiography QC’ on page 242 .
4
Compare the measured A and B dimensions with the reference dimension
values, A
ref
and B
ref
on Chart 4 (‘Drystar 5500/5503 Geometric Consistency
Control Chart’). Refer to ‘Charts for general radiography QC’ on page 242 .
The differences between the measured dimensions of A and B and the reference
values A
ref
and B
ref
should be less than or equal to 1.0%.
5
Check for image distortion.
6
Calculate the aspect ratio by dividing A by B.
The result must be 1 +/- 0.01
Make sure to measure distance A from the left edge of the left line to the
right edge of the right line and distance B from the upper edge of the
upper line to the lower edge of the lower line.
We strongly recommend using a 30 cm (12 inch) machinist scale with
0.5 mm divisions (1/64 inch).
If the image size or distortion values exceed the limits, contact Agfa
service to resolve the problem.