Originally Posted by mrmikel
If you must start with a PDF, as they said the very worst source, use mobipocket creator to convert the PDF to HTML, then load that HTML into sigil to fix the inevitable errors and finish it up without all the extra junk added by calibre. If you do that, break it into sections for each chapter to make sure it loads and plays well in devices.
It doesn't really matter all that much what software is used to convert the PDF. Because 100% of the time you will NEED to do a full A/B compare of the PDF to converted file. It's the only way to find all of the errors. Even Adobe Acrobat cannot export without errors. But starting with PDF as the source is the dumbest thing one can do when making an eBook.