Epson 836XL - Expression - Flatbed Scanner User Manual page 19

If the squares are centered, click Ok. You see the MonacoSCAN main
window. See Calibrating and Evaluating the Results to complete the
calibration steps.
If any white squares lie outside any image squares, deselect Show
grids and click the Revert button. Then repeat steps 2 through 5 to
crop the image again.
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