Canon 3749B002 On-Screen Manual page 827

If it is difficult to pick the best pattern, pick the setting that produces the least noticeable
horizontal white streaks.
(C) Less noticeable horizontal white streaks
(D) More noticeable horizontal white streaks
11.
Confirm the displayed message and press the
The second pattern is printed.
Important
Do not open the Scanning Unit (Cover) while printing is in progress.
12.
Check the printed patterns, and use the
pattern in column H that has the least noticeable vertical streaks.
Note
If it is difficult to pick the best pattern, pick the setting that produces the least noticeable vertical
white streaks.
(E) Less noticeable vertical white streaks
(F) More noticeable vertical white streaks
button.
OK
button to input the number of the