Polaroid SprintScan SS35 Repair Manual page 67

Slide Scanner Repair Manual
Magnification Adjustment
Note: To check magnification, measure the delta time between the single vertical lines between
each set of line pairs of the waveform signal. Use the dual time delay function of the
oscilloscope. See Figure 3-9.
There should be 1000 +/- 10 pixels between lines 2 & 5. The slide scanner
operates at 0.5 microseconds per pixel. The specified limit for magnification is 1.0%.
Example - To calculate magnification for 1005 pixels:
Magnification = Number of pixels times the slide scanner speed = 1005 x 0.5 usec = 502.5 usec
1. Loosen the two (2) screws that secures the optical block assembly (Figure 3-14) to the controller
PC board.
2. Loosen the two (2) screws that secures the lens block assembly to its bracket.
3. Slightly move the lens block assembly in or out.
4. Tighten the two (2) screws that secures the lens block assembly to its bracket.
5. Tighten the two (2) screws that secures the optical block assembly to the chassis
assembly.
6. Recheck focus as explained in the focus adjustment and then recheck magnification.
Note: Always recheck focus after each magnification adjustment.
7. Repeat steps 1 through 5 until magnification is equal to its specification:
Notes: • Actual time is a function of slight variations in lead screw pitch and clock
frequencies from unit lot-to-lot.
• LabVIEW Test will suggest relative correction in usec's for optimum
performance in it's test results. The result is listed as Best mag time change .
500 = +\- 5.0 usec
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Calibration and Adjustments