I have seen a video footage of a machine used by a library (sorry, I did not record the details), which opened the book about 120 degrees. One arm took the next page down to horizontal level, a horizontal glass sheet was put on the page to make sure the page was truly horizontal, the flash light was activated and the class sheet was removed and the sequence restarted.
The sequence took about 2-3 seconds. Apparently some auto-focus was used, since the distance between the lens and the paper changed each time a new page was added.
The odd pages could be processed in one run and a separate run would be required to process the even pages (including flipping the page and inverting the picture order).
Put a heavy glass sheet on the page you are photographing, this will flatten out the page and you will get equal focus across the page.
If you do the trouble of carrying the manuals to the print shop, why not let them scan the pages ?
In a law abiding print shops you may have to prove that you have the copyright to make your own copies.
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Then there is the question how to store the scanned pages and also how to distribute the (web) pages in a bandwidth efficient way.
I previously thought that storing and displaying the scanned pages as simply bilevel (1 bit/pixel) bitmaps (typically run length encoded as in faxes) would be sufficient, however, such page pictures look horrible and the OCR software does not reliably make sense of the text.
1 bit/pixel is really too little and 8 bits/pixel would be excessive. How many bits/pixel would be sufficient for pleasant visual rendering or required by OCR software ?