Canon mp280 series On-Screen Manual page 592

When you have entered all the necessary values, click OK.
Note
If it is difficult to pick the best pattern, pick the setting that produces the least noticeable vertical
white streaks.
(A) Less noticeable vertical white streaks
(B) More noticeable vertical white streaks
11.
Confirm the displayed message and click OK
The third pattern is printed.
Important
Do not open the Scanning Unit (Cover) while printing is in progress.
12.
Check the printed pattern
Enter the numbers of the patterns with the least noticeable horizontal stripes in the associated
boxes.
Clicking the patterns with the least noticeable horizontal stripes in the preview window, will
automatically set their numbers in the associated boxes.