UPDATE 010314: I wrote this article before I did any real research into Calibre. Considering the vast number of hits this blog post is generating, I knew there was a call for information about how to convert a Word file to MOBI in Calibre. I found a fix and I wrote a series of posts about it. Part 1 (Styling in Word), Part 2 (the HTML file) and Part 3 (Conversion in Calibre). It’s not a quick fix (or magical), but it’s not difficult either.
Don’t get me wrong. I like Calibre. It’s quick, it’s handy, and it has an attractive screen display that I far prefer over Adobe Digital Editions or the Kindle Previewer. Since I don’t have a device capable of reading EPUB files, it’s also useful for checking the formatting on files I create for others.
What it’s not good for? Converting EPUB files into MOBI files for commercial purposes.
Having seen some horrendously broken ebooks that had been converted through Calibre, I have long suspected that Calibre was the wrong tool for the job. I assumed it was user error, a problem with the source file and/or the html, and if the formatter did a really good job with the initial file, Calibre wouldn’t muck it up.
I was wrong. The problem is with Calibre.
I converted an EPUB file to a MOBI file with Calibre. I then took the exact same file and converted it with KindleGen via the Kindle Previewer. The above screenshots are the results. Same page, same settings, same device (Kindle Paperwhite).
In the recent ebook formatting contest, I saw squishy line spacing in every single ebook that had been converted via Calibre.
So maybe the problem lies in the subtle differences between the html coding for EPUB and MOBI. I ran a file I had made specifically for Kindle through Calibre. Squishy lines. I took that Calibre-generated file and ran it through KindleGen. Squishy lines.
Could Amazon be taking care of the problem? I downloaded samples from the contest entries. Squishy lines.
Why does Calibre do this? I have no idea. It just does.
Why is it a problem? Because for many readers, myself included, Kindles (and other ereaders) make reading comfortable again. My eyes are old, plus I spend all day in front of a computer. My eyes are tired. With the Kindle I can change the font, adjust the font size and change the line spacing for optimal comfort. Squishy line spacing is hard on my eyes. When I try to read an ebook that I can’t adjust for my comfort, I get irked. When I’m irked, that author/publisher ends up on my Don’t Bother list. (Your future sales, folks)
There are alternatives to Calibre. If you are converting a Word or html file, use MobiPocket Creator. If you have a simply formatted file, it will generate a prc file you can upload to Amazon and it will work. If you have an EPUB or html file, you can use the Kindle Previewer (converts with KindleGen). A warning about the Kindle Previewer–what you see is not always what you get. Trust but verify and test your files on an actual device if you can.