Polaroid SprintScan SS35, Руководство по ремонту

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Slide Scanner Repair Manual Diagnostics and Troubleshooting
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Left and Right Color Misalignment Windows
The graphical representation of color misalignment is shown on right side of the test panel.
This shows the misregistration data from the top to bottom left and right sides of the chevron
pattern that’s part of the GMT target used in this test.
What is actually shown is the variation in misalignment up and down the carriage movement. A
good carriage movement system has relatively small variations, a bad carriage system has
large variations that are usually in certain spots (example: a burr or dirt in one spot on the
leadscrew, within the ball slide, or on the guide rail). In practice, the point defect will be seen in
a scanned image as a color fringe that always shows up in the same spot on the image.
Our test result shows sinusoidal waveforms that are approximately centered around a zero (0)
point on both the right and left side. Leadscrew problems are fairly easy to spot using this
graphical method.
Mag and Tilt Adjustment Effects
Mag adjustments move the entire sinusoidal waveforms (both left and right sides shown on the
graphs) up or down together corresponding to vertical red to blue misalignment.
Tilt adjustments move the left side and right side waveforms in opposite directions depending
on the direction of the adjustment.