Hey Archie,

A couple of ideas, but you may have already thought of them:

First, look to see if your scanner has contrast and brightness switches/dials on the actual device somewhere. My old Epson all-in-one has one, but it's not obvious what it is or does by looking at it. If so, play with those until you get white to look white in scans.

The other idea is to look on Canon's website for updated drivers.

Bryan