Polaroid SprintScan SS35, Руководство по ремонту

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Slide Scanner Repair Manual Diagnostics and Troubleshooting
Calibration
The two (2) hexadecimal digits assigned to calibration type errors indicate a failure of the slide
scanner's self-test (calibration) diagnostics routine.
The first calibration is performed at the first requested scan. It is also performed when the slide
scanner detects a specified amount of drift in the lamp or front end during subsequent scans.
Note: SS35 PLUS calibrates fully before each scan.
The following types of adjustments occur during the first calibration:
• Base line integration time to ensure a minimum signal and mitigation of saturation
• Analog gain and offset for base line neutral settings
• Digital uniformity offset calibration
• Digital uniformity gain calibration
• Bad pixel identification
Subsequent scans may require additional analog gain and offset and/or integration time
adjustments to accommodate white points requested by the host or film tables, as a function of the
specific calibration algorithms.
A drift check is performed with each scan to verify the stability of the front end. Each calibration
that requires a significant change in the front end settings necessitates a recalculation of the
digital uniformity offset correction during the actual scan.
Causes of calibration failure are usually due to a defective lamp, obstructions in the optical path, a
defective sensor (CCD) PC board, a defective main controller PC board, defective filter, or
misaligned filter wheel (Only for original SS35 and SS35 ES up to serial no. B6xxxxxxD).
Refer to Table 5-4 for a list and definition of all calibration type error codes.
Before attempting to correct a calibration error check the video output signal (Figure 5-1) from
the provided test points on the main controller PC board to make sure no irregularities exist.
SS35/SS35 ES Test Points SS35 PLUS Test Points
J8, pin 2 - LSYNC LSYNC
J2, pin 8 - Video ADIN