White thick line while scanning

White thick line while scanning

Hello Therese.

Does the white line run vertically through your scanned image?  Here are some possible reasons for the white line:

1.  Bad pixels on the CCD.  The CCD is the sensor that actually "sees" the images and converts it to electrical signals for processing.  If there are defective pixels in the CCD, it will manifest as white lines on the scanned image.  Think of it as a sort of blind spot.  If this is the error then you may have to bring your scanner in for repairs or replacement.

2.  Error in calibration.  Scanners usually perform white calibration.  If there is anything that blocks the CCD while it is calibrating, then the scanner might mistake that blockage as a problem with underexposure.  It will then try to compensate by increasing the brightness.  It is possible that the white line you see is actually just a very bright portion due to the calibration error.  Check the scanned image to determine if it is really white or just a very bright image of the original.  Try cleaning the glass of the scanner bed especially on the portion that corresponds to the white line and perform white calibration again.  Consult your scanner's manual on how to re-calibrate.