Even if you place originals in the ADF or on the exposure glass correctly, margins of a few millimeters on all four sides of the original might not be copied.
Missing Image Area
Leading edge: 3 mm (0.2 inches)
Trailing edge: 2 mm (0.1 inches)
Left edge: 2 mm (0.1 inches)
Right edge: 2 mm (0.1 inches)