Superscript problems with Kindle/Kindle DX

[iain robinson]

Hi all

I'm having problems with a job which requires ePUB and mobi files - the superscript elements (endnote markers) are causing larger than normal gaps between the lines in Kindle Previewer when viewing as Kindle or Kindle DX devices. Other Kindle devices and the ePUB is fine.

Initially I was making text superscript by using a span tag (class="superscript") and using the usual CSS declarations which I use successfully for ePUB to make it superscript. This didn't work for the old Kindle devices so I tried the <sup> tag, with and without CSS to try and solve the problem but without success.

Does anyone have some magic CSS which will solve the problem for old Kindle devices? I've looked around the web a lot and seen lots of discussion of this issue but no solutions.

If it is not possible I will just have to have the endnote markers non-superscript (eg, [1], [2] etc) but would be happier with superscript ones.

thanks,
Iain

[Jellby]

Originally Posted by iain robinson

Does anyone have some magic CSS which will solve the problem for old Kindle devices? I've looked around the web a lot and seen lots of discussion of this issue but no solutions.

I guess there's no such thing, because old mobi format (the one used by Kindles) does know nothing about CSS. All the CSS support you can see is in the converter, which takes your input file and transforms it into mobi HTML-like code. As far as I know there's nothing in mobi code that allows you to control line spacing, so what you see is just normal and expected behaviour (it's usually the same in ePub and HTML+CSS, unless you change the default settings). The solution, as you say, is either not using superscripts or just living with that.

[iain robinson]

Thanks Jellby - I thought that was probably the case but I just thought I'd check with the experts before I decided for sure.

cheers,
Iain

[dgatwood]

I would have expected that reducing the font size of the text inside the superscript element would be sufficient, but it does not appear to be. Perhaps KindleGen is enforcing a minimum font size percentage or something....

[iain robinson]

I did play around with that but I still ended up with bad line spacing. I've given up - I'm just putting them in square brackets (not superscript), which is a shame but I can't spend any more time trying to get it to work.

[DiapDealer]

No need to spend a single second trying to "get it to work". You simply can't do anything about it with the older mobi format. Superscript = increased line spacing. Period. Same thing with raised (large) caps. Nothing to be done.

[Doitsu]

Since the Kindle system fonts cover all Unicode superscript numerals (⁰ ¹ ² ³ ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ *), which don't affect line spacing, it'd would be theoretically possible to replace regular superscript numerals with their superscript Unicode equivalents. However, since the glyphs for 1-4 and 5-9 are apparently provided by different system fonts, this would only work for single digit footnotes or maybe multiple asterisk footnotes.

IMHO, this would be overkill since the number of non-KF8 compatible Kindles is most likely negligible and there are far worse compatibility issues.

(The test file was compiled with Kindlegen 1.1; the source files are embedded.)

[iain robinson]

Thanks. That's interesting to know, but a bit of a faff. This job has a lot of notes.