All default scan options are stored in the scan driver configuration file, /etc/sane.d/lexmark_nscan.conf. Changing the values in the scan driver configuration file updates the default settings. The settings are reflected in the application.
XSane stores the most recently used scan settings in the ${HOME}/.sane/xsane directory. In order for XSane to reflect the changes you made in the scan driver configuration file:
From the menu bar, choose File Quit.
In the command line, type
.Restart XSane.