Even if you place originals in the ADF or on the exposure glass correctly, margin of a few millimeters on all four sides of the original might not be copied.
Missing Image Area
Leading edge: 3 ± 2 mm (0.12 ± 0.08 inches)
Trailing edge: 2 ± 2 mm (0.08 ± 0.08 inches)
Left edge: 2 ± 1.5 mm (0.08 ± 0.06 inches)
Right edge: 2 + 2.5/-1.5 mm (0.08 + 0.1/-0.06 inches)