Canon MX450 series Online Manual page 23

When Short edge is Selected for Binding Side in Document Scan Orientation
Settings...
Place the documents without changing the orientation of the output documents.
9. Click OK.
Scanning starts.
Note
Click Cancel to cancel the scan.
Scanned images are saved in the folder set for Save in in the corresponding Settings dialog
displayed by clicking Settings.... In each Settings dialog, you can also make advanced scan settings.