Check on different systems
When checking a new ebook (especially one from a new contractor), we always recommend using at least two different platforms (also referred to as systems or engines). For instance, Digital Editions on a PC, the EPUBReader addon in Firefox, and iBooks on an iPhone all have different epub-rendering engines, and will give you a sense of the range of reading experiences users will have. (For example, Adobe Digital Editions has poor support for styled capitalization, where iBooks ignores many of the designer’s sans-serif font preferences.)
It’s good also to check on a smartphone to see how the text behaves on a small screen. Small and large screens will show up different problems:
- A device with a small screen (less than, say, 5” diagonal) can help detect various formatting problems, such as hard-coded word breaks or headings with font sizes that are too big.
- A device with a large screen (above, say, 19”) can help detect low-res covers and missing page breaks.
Also see our suggestions for choosing epub-reading software.
If you’ve outsourced your epub creation, there is usually some discussion or decision-making to be done, as an ongoing conversation, about house styles and other issues, such as how copyright pages are handled.
Common problems to look for
In the short to medium term, it is still necessary that every ebook conversion is visually checked by a person, preferably one familiar with the book (e.g. the editor). In particular, watch for:
- clear covers that display neatly across ereading systems (e.g. some covers display nicely in one system and badly in another; sometimes a compromise is necessary)
- missing text, especially in elements like captions, sidebars and footnotes
- missing, incomplete or inaccurate metadata (e.g. ISBN or author name, stored in the ebook and displayed differently in each ereading system)
- broken and/or incomplete navigation (e.g. in clickable tables of contents; in early epubs many toc.ncx files included invalid characters that broke the TOC off)
- missing page breaks and important spacing between paragraphs (e.g. the distinction between a paragraph break and a line space is very important in narrative prose)
- problems around non-breaking spaces (e.g. in ’10 000′) and special characters (e.g. > becomes > or >). This can signal a problem with character encoding.
- problems with characters available only in complete fonts, such as ff, fi, fl, ffi, ffl ligatures (try a quick search for any of these letter combinations and see what you find)
- broken hyperlinks (when there are many clickable links, often only a spot check is possible)
- low-res images
- font size and font family inconsistencies (especially where fonts have been embedded)
- bad breaks around images, especially where images are very large
- spelling and capitalisation errors in the navigation/clickable table of contents (these are often retyped during conversion, or inherit capitalisation problems from sloppy print-typesetting practices)
If you’re creating epub ebooks, or want to run some technical checks on epubs from contractors, also see our epub-specific testing suggestions.