The company I send my books out to to scan never have that dirty edge.

Those dirty edges are noticeable and distracting when trying to read a PDF book.

I thought maybe the dirty line is caused by my old paper cutter....but even with a relatively new book ( I keep my books inside plastic zip lock bags to prevent dust, yellowing etc. ...the dirty edge is there when scanning but NOT there when look at the page with naked eye.

Ragged edges don't appear to be a problem but any amount of glue from the backing left on the pages and they don't feed properly causing a jam.

OR all the very edges on one side of the page has a dirty looking edge that looks horrible when the book pages are put together into one PDF file

I have to scan EACH book page and then INDIVIDUALLY upload EACH book page into PAINT and either erase that dirty edge or move the border inward to erase it.