Avision AD250F - Manual (Page 103)

User’s Manual
4-67
Notes to print the patch codes:

Use blank white paper.

Set the scaling to 100%. The sheet is not recognized
correctly when printed in a size smaller than the original.

Do not use toner saving mode. The sheet is not recognized
correctly when the print is too light.

Do not use thin paper in order to avoid bleed-through from
the back.

When you copy a patch code sheet that you printed out,
make sure to copy by the same size and brightness as the
original copy.

Use the same sheet repeatedly may decrease the
recognition accuracy due to accumulated dirt on the sheets.
If the sheet is not recognized correctly or gets smudged,
replace it with a new sheet.