Canon imagePRESS C800 Series Troubleshooting Manual page 33

Chapter 1
2-5) Place the output second test page face down on the platen glass with the black strip to the rear and then press "Start Scanning".
[Reference]
Make sure to place the last output if the multiple third test pages are output. To perform more precise full adjustment, you can increase the number of sheets for test
pages in "Number of Sheets to Output for Test Page". In this case, multiple third test pages are output.
2-6) Remove the second test page from the platen glass > press "Start Printing". Third test page is output.
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