Canon imagePROGRAF TA-20 MFP 24" Large Format Printer with L24ei Scanner and Stand Kit - Manual (Page 732)

Borders appear in borderless printing
Check the items below if white streaks or border appears on the edge of the paper in borderless printing.
Check 1 Did you try adjusting the position of the Print head?
Adjusting the position of the Print head improves the printing accuracy.
Adjusting the Print Head
Check 2 If printing full-scale borderless, is the selected paper wider than the source
size?
For borderless printing at actual size, use roll paper that has the same width as the actual page size.
Printing Full-Size without Margins (Windows)
Printing Full-Size without Margins (macOS)
Check 3 Does the source file have margins?
Check that the printing image data does not have any objects like crop marks and transparent objects.
Check 4 Is a margin set in application software?
Check that no margins are configured in the application software you are using.
Check 5 Is the setting of Extension for borderless printing in the touch screen menu
small?
Increase the setting of Extension for borderless printing in the touch screen menu to more than the current
setting. (Select a larger number than the current setting.)
Menu Structure
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