Slide Scanner Repair Manual Diagnostics and Troubleshooting
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Motion Problem Examples
Example 1 - Figure 5-13 shows an example with a problem leadscrew.
Two things stand out in this example. One is the large peak swing graphically illustrated at
approximately line #1200. This large swing indicates a point defect with the leadscrew or the
guide rail. A second item of interest is the large Peak swing misalignment of 2.33 pixels.
When 2.33 is compared to the Peak misalignment limit of 1.10 it is more than twice as large.
The result means that mag or tilt adjustments alone will not fix this problem. You must deal with
carriage movement problem before any other adjustments can be made.
Note: A Mag time change of -2.3 microseconds is suggested by the test to eliminate
the .29 pixel vertical misalignment.
As you now realize, if you did the adjustment the peak misalignment would go to 1.50 pixels
(1.21 now + .29 suggested adjustment). Since the large point defect is still present, the
scanner will still not pass the motion test.
Figure 5-13. Leadscrew problem