User Manual

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2831A EN 20041201 Advanced operation (key-operator mode)
DRYSTAR 5302 USER MANUAL
Performing the Weekly QC tests
Spatial Resolution, Artifact Test and Low Contrast Visibility
To identify artifacts and verify spatial resolution you must perform the
following test weekly or as needed for troubleshooting image quality
problems.
1 Check the QC test image visually for artifacts: no significant disturbing artifacts
should be visible.
2 Check the spatial resolution.
The test film also shows three squares which each contains an oval. These 3 ovals
contain 3 groups, each having 5 dots. All five dots of each group must be visible with a
magnifying glass. The smallest cluster of 5 dots are only visible if the viewing
conditions are good.
3 Check the Low Contrast Visibility at both the high (100 / 95%) and low end
(0 / 5%) of the density scale. You should be able to see the circle in the square
(refer to item 1 on the ‘QC test image’ on page 52) and the upper circle (refer to
item 2 on the ‘QC test image’ on page 52).
4 Record these values on the Drystar 5302 Chart 3 (Drystar 5302 Artifacts and
Spatial Resolution Control Chart).
Good viewing conditions are important for the correct interpretation of
both diagnostic and test images. Make sure that the lightbox intensity
(luminance) is between 2000 and 4000 cd/m² (4500 and 6500 °K). Use a
magnifying glass and use shutters to collimate. Make sure the ambient
light is low.
In case of significant artifacts, insufficient spatial resolution or failure of
any other recommended QC tests, the cause of the problem must be
identified, and corrective action must be taken before the Drystar 5302
can be used for any further clinical imaging.
Refer to‘Preventive maintenance schedule’ on page 59 and ‘Maintaining image
quality and resolving image quality problems’ on page 173 of the Drystar 5302
Reference manual, or call your local Agfa service organization for
assistance.