My first job out of college was scanning books for the Internet Archive down in the basement of the Library of Congress. Their scanning machines used a foot pedal to raise and lower the glass Platen, so I'd use one hand to flip the page and wiggle the cradle to get things nice and flat and the other would snap the photo. You can get pretty fast after a while, but boy is it mindless. Older books that had been rebound a couple times already were the hardest to work with as you have the least amount of margin. There's a bunch of different sized dowels that we would put under the spine in the cradle so the glass could gain a couple millimeters of margin, just enough to avoid cutting off text. Worst case scenario the book had to be unbound in order to capture. I did get to flip through a lot of cool old illustrated catalogues like this: https://archive.org/details/illustratedcatal00keil/page/14/m...