Case 17: Dose Irregularities (I.e., Bad Correspondence Of Mas And S Values, Etc.); Case 18: Image Disparity; Case 19: White Blotches; Case 20: Black Blotches - Konica Minolta REGIUS 190 Service Manual

4.3.18 Case 17: Dose irregularities (i.e., bad correspondence of mAs and S values, etc.)

Phenomena
Incorrect sensitivity calibration.
1
The log-log curve created by measuring the val-
2
ues for "mAs" and "mR" is not linear. (check the
linearity for each of 1mAs, 10mAs, 100mAs
against mR)

4.3.19 Case 18: Image disparity

Remedy
Check the bulb dose (i.e., measure the mR value and confirm whether the dose is correct)
1
Confirm the exposure settings. (Refer to the recommended value in the medical ledger)
2

4.3.20 Case 19: White blotches

Remedy
Clean any dust from the plate and then check the solid image.
1
If the blotches remain, there is a possibility of plate defects and the plate should be replaced.
2

4.3.21 Case 20: Black blotches

Remedy
1 Erase the plate and re-expose.
4.3.22 Case 21: Monitor display problems (OK with film)
Remedy
Brightness between the viewer and the monitor does not match. Regenerate the display's LUT.
1
Cause/Remedy
Repeat the sensitivity calibration.
Request the X-ray tube manufacturer for remedies.
REGIUS MODEL 190 Service Manual Ver.1.00 2004.11.01
4.3 Troubleshooting for Image Quality
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