As longtime followers of this blog know, I think cover images are A Big Freaking Deal with eBooks. I like seeing the book covers – both when I first start reading a book… and as a preview. When you load (or sideload) an eBook and just get the default cover, it looks… unprofessional. Doesn’t matter who made it, it just looks cheap.
And, to my chagrin, I’ve been doing it wrong.
Luckily, the fix is a simple tweak to content.opf. Previously, I told you to do this:
Yeah, no. Change it to this instead:
and then when you’re declaring your images, make sure you declare it as cover-image, like so:
I’ve updated my helper script to do this automagically – if you’re on a Mac or *nix, you can use it. And if you want to see the whole content.opf, my default style.css, and (and my other eBook utilities), swing on by this GitHub repository.
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Is this what was causing the error you mentioned in an earlier post, the one about cover displaying differently in different versions of Kindle?
Unfortunately, I don't think so. I'm pretty sure that's just a resolution issue – or more accurately, an aspect ratio issue.