AGFA Drystar 4500 Reference Manual page 141

Verifying Acceptable Spatial Resolution, Artifact Levels and Low
Contrast Visibility
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.
To verify acceptable spatial resolution, artifact levels and low contrast
visibility, proceed as follows:
Print the QC Test image or use the previously printed QC Test image used to
1
establish the daily operating density levels.
Visually check the QC test image for artifacts: no significant disturbing artifacts
2
should be visible.
Check the spatial resolution in each of the three ovals. Within each oval there
3
are three groups, each having five dots. All five dots of each group must be
visible with a magnifying glass. The smallest cluster of 5 dots is only visible if
the viewing conditions are good.
Check the Low Contrast Visibility at both the high (100 / 95%) and low end
4
(0 / 5%) of the density scale. You should be able to see the circle in the square
(refer to item 1 on the
item 2 on the 'QC test image'
Record these values at the top of the Drystar 4500 Chart 3 (Drystar 4500
5
Artifacts and Spatial Resolution Control Chart). Refer to
on page 207.
These charts will be used for the weekly quality test. For more information,
6
refer to 'Performing the Weekly QC tests'
In case of significant artifacts or insufficient spatial resolution, the cause
must be found and the problem solved before any further clinical films can
be printed.
Refer to
page 191
local Agfa service organization.
2800E EN 20050215
'QC test image'
on page 139).
'Maintaining image quality and resolving image quality problems'
and ''Preventive maintenance schedule'
on page 139) and the upper circle (refer to
on page 144.
on page 168, or call your
Advanced operation (key-operator mode)
D 4500 R
RYSTAR EFERENCE MANUAL
'Quality Control Charts'
on
141