Working on the PDF
Note: You need a good PDF editor to do this. Most designers and typesetters have Acrobat Pro. If you don’t, you can try other PDF editors like Foxit Phantom 2.0, PDF Studio or Proview. We’ve not tested these options extensively.
- Create one PDF. If you’re working from separate PDFs, assemble them into one PDF of the book interior. (You can do the cover later.)
- Crop the pages. If you’re working from a print PDF, use your PDF editor to remove crop marks. Check whether the PDF uses different crop positions for left and right (odd and even) pages.
- Downsample images and optimise. Downsample the images from a high print-based DPI to something better for ebooks, around 150dpi. In Acrobat Pro, use the Advanced Optimisation tool for this, and downsample all images over 225ppi to 150ppi. At the same time in the Advanced Optimisation dialogue, here are our recommended options, which you can enter and save as a preset for your future use:
- Do not discard or change Fonts or Transparency.
- In ‘Discard Objects’, check only ‘Discard all alternate images’.
- In ‘Discard User Data’, check only ‘Discard all comments…’ and ‘Discard private data…’.
- In ‘Clean Up’, check everything except ‘Discard unreferenced named destinations’.
- Create and add the covers. Repeat this process for the front and back cover PDFs. You should create one page of the front cover cropped to the same page size as your interior, and one for the back cover similarly. Then add those as pages to your main PDF. For a PDF ebook, your first page must be your front cover. You can add the back cover as the last page in the PDF.
- Fix page labels. When designing a document for print, your first page is usually page 1 of the document, not your cover (and, if you’ve used them for content, inside front cover, back cover, and inside back cover). Now you must relabel the covers so that page numbers as numbered by your PDF editor (in the page X/X box that you can type into to jump to a given page) are the same as the visible page numbers (folios) on your actual pages. If necessary, renumber the opening pages (e.g. cover, inside front cover) in alphabetic letters (a, b, c) or roman numerals, so that your document’s first page is page ‘1’ in Acrobat’s own numbering. Acrobat and other PDF editors call these numbers ‘Page Labels’.
- Add bookmarks. This is the bookmarks-panel navigation that ereaders show to users for clicking to various places in the ebook. Look to the visible Table of Contents for hints on what to include, if the book has a TOC. In your PDF editor, show the Bookmarks panel, and create a Bookmark for the cover (With the Bookmarks panel and cover page showing, click ‘New Bookmark’ and call it ‘Cover’). And then one by one add bookmarks for any other pages that need entries in the bookmarks/nav panel.
- Add hyperlinks. If necessary (e.g. if pages contain paid advertising), add hyperlinks to make pages or page areas clickable to web pages.
- Add metadata. Add basic metadata, including a copyright notice and description in the Document Properties dialogue box by going to File > Properties > Advanced Metadata. The more metadata you include, the better. In the Document Properties, include at least the title and author.
- Set the PDF’s Initial View. You also need to set the PDF’s Initial View in your PDF editor to something suitable for ereaders. In Acrobat Pro and Foxit Phantom, go to the Document Properties dialogue box, and the Initial View tab. The Initial View should specify:
- Show ‘Bookmarks Panel and Page’;
- Display: ‘Single page’ (or ‘Two-up (cover page)’ if spreads are important, in which case you may need a blank page after the cover to retain the correct verso/recto layout);
- Zoom: ‘Fit page’;
- Show ‘Document Title’; (not ‘File name’;)
- Check the initial view. Save and close the PDF, and open it again. It should now open with the Bookmarks panel showing, the document title (not file name) showing in the bar at the top of the PDF editor, and the whole of the first page fitted to the viewing area.
- Check the bookmarks. Click on the Bookmarks to see that they work (i.e. they go to the correct places when clicked), and that all pages are there and in the right order. If you have the time, make sure everything works by checking every page. (E.g. sometimes PDFs don’t display transparency correctly, and you won’t know unless you check.)
Troubleshooting
Images not displaying
On some PDF readers, like Adobe Digital Editions, some images might not display. ADE is a common e-reading application for PDF ebooks, and its engine is the same Adobe-based one that powers many other ereaders. Sadly, it has problems, including the fact that (at least in earlier versions) it will not show images saved with JPG2000 compression (and perhaps other image formats too). If your PDF contains any such images, they won’t display in ADE. So, check your ebook in ADE looking for missing images. (Tip: In ADE, check the book’s ‘Item Info’ and see whether there’s a ‘Document uses unsupported PDF feature’ warning. If there is, you’ve probably got an image compression problem.) If your PDF has this problem, regenerate the PDF from the source files trying any setting that avoids JPG2000 compression. If your source file is a PDF, try printing it to PDF using a PDF print driver (such as the Adobe PDF printer, which should come with Creative Suite), or export to PostScript and then open the .ps file with Adobe Distiller to generate a new PDF. You’ll probably lose any bookmarks and interactive features by doing this, unfortunately, and will need to recreate them in the resulting PDF.