AGFA CR 30-X - Possible Reasons for a Failed Shading Calibration; Appendix: Changes in the Shading Calibration Procedure if Full Leg; Full Spine Cassettes Are in Use

DD+DIS150
.06E
Repair and Service
Adjustments and Calibrations
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3.1.2 Possible Reasons for a failed Shading Calibration
There are mainly following reasons for a failed shading calibration:
 Dirt or dust in the optical path
 Cassette wrong exposed (too high / low dose)
 Cassette not exposed on its full surface (wrong collimation)
 PMT exposed to direct sunlight before calibration (in this case PMT has lower
sensitivity)
 PMI board carrier (with mounted PMT) misaligned
3.1.3 Appendix: Changes in the Shading Calibration Procedure if Full Leg / Full Spine
Cassettes are in Use
NOTE:
This section describes the changes in the shading calibration procedure, if a FLFS
cassette is used. See section 3.1.
Reason for different pro
ceeding: In opposite to Genrad (General Radiology)
cassettes, FLFS cassettes do not have the complete IP area covered with a
backscatter protection: The lead foil does not cover approximately 10 mm on the
upper and lower side of the cassette.
FLFS
FLFS
10 mm
10 mm
Backscatter
Protection
Genrad Cassette FLFS Cassette
Figure 45
Edition 1, Revision 3 CR 30-X Chapter 3.6 / 33
10-2009 Type 5175 / 100/110 Agfa Company Confidential