NORMI 13 (T42023)
Operating Manual - Constancy Test
D703.131.00/03 en
25
3.4.8 Coincidence of the light field
and the radiation field
The deviations referred to the image receptor
plane shall not exceed 2% of the distance (r)
between focus and image receptor in each case.
and
Magnitude of the horizontal devia-
tions between light field and radia-
tion field
and
Magnitude of the vertical devia-
tions between light field and radia-
tion field
V
Imaging scale according to DIN
6868-150 that was defined and
documented during the accep-
tance test as a criterion for the
constancy test
3.4.9 Artifacts
The X-ray image must be free from structures
whose size, shape, edge sharpness, and differ-
ence in optical density or luminance relative to the
surrounding area could affect the diagnosis.
3.5
Constancy Test Report
The test report shall include the following mini-
mum information:
– Indication that the test was performed accord-
ing to DIN 6868-13
– Operator of the X-ray installation
– Tested installation
– Imaging system (image receptor type, analysis
software)
– Test equipment
– Exposure parameters (e. g., distance between
focus and image receptor, distance between
focus and test object, tube voltage)
– Reference values, maximum deviations and
current parameter readings
– Date and name of the person performing the
test
We recommend using a standardized protocol
where the test results can be entered in tabular
form. This makes it easier to compare them to the
initial values. The standard DIN 6868-13 provides
a model form sheet.
