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You can adjust the scanner settings for the MF451 using the MF scan utility that installs onto the computer along with the drivers. You will find the Utility in your list of installed programs under Canon Utilities. Once you open the scan utility, you can click the settings option in the lower right to access the settings. You can adjust the settings for the scan utility and the scan options that are on the operation panel using the information found at the link HERE.
12/05/2023: New firmware updates are available.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.