Libra 2 Kobo-newbie (more or less) and some font issues

[beedaddy]

After years using other eReaders (my last Kobo device was Kobo Glo) I received yesterday a Kobo Libra 2. The display is amazing – the best I've seen so far. But I quickly remembered one or two of the Kobo's shortcomings.

All my ebooks are epubs, but IIRC, the kepub-engine is a little bit more advanced and better maintained as the epub-engine (epub3?). And I like the per-chapter-infos which come with kepubs. So I prefer to kepubify the ebooks with calibre.

But, and now we come to my font problems: I have the impression that ligatures and kerning (still?) are a problem with kepubs, or is it just me? And fonts in gerneral seem to be problematic. I like the fonts Literata and Bookerly very much. But, with Literata I get very big line spaces and no kerning and no ligatures at all. With Bookery, I'm not sure about kerning/ligatures, but italic text is always displayed as bold-italic.

So, maybe you can bring me up to date:
- Are kerning and ligatures still not supported within the kepub-engine?

- Why is the line spacing (only) with Litarata so huge? I took the static fonts (Literata-Regular.ttf, Literata-Italic.ttf, Literata-BoldItalic.ttf, Literata-Bold.ttf) out from the font package. But there are other variants (Literata_18pt, Literata_24pt, Literata_36pt, …).

- Using Bookerly: Why is italic displayed as bold-italic? Am I doing something wrong with fonts import? I put the files Bookerly-Regular.ttf, Bookerly-Bold.ttf, Bookerly-BoldItalic.ttf and Bookerly-Italic.ttf in the fonts-directory. Is the naming wrong?

- I applied some patches ("My 10 line spacing values", "Set KePub hyphenation", "Unify font sizes"). Maybe I missed a useful patch that would help here?

I have attached two photos: One showing Bookery with (wrong) bold-italic text and one showing Literata with the big line space and no ligatures etc.

[beedaddy]

As I now found out, while digging more in the forum threads, adding this in the Kobo config file to the [Reading] section seems to add ligatures:

webkitTextRendering=optimizelegibility

This is a big improvement. I wonder why it's not a default.

[Sirtel]

Originally Posted by beedaddy

As I now found out, while digging more in the forum threads, adding this in the Kobo config file to the [Reading] section seems to add ligatures:

webkitTextRendering=optimizelegibility

This is a big improvement. I wonder why it's not a default.

Because it can cause problems with word spacing when you read fully justified text. I never enable it for this reason. Good word spacing is far more important to me than ligatures.

[beedaddy]

Originally Posted by Sirtel

Because it can cause problems with word spacing when you read fully justified text. I never enable it for this reason. Good word spacing is far more important to me than ligatures.

Yes, even worse it causes funny spacing within words (letter-to-letter).

webkitTextRendering=geometricPrecision

seems to be better (for me).

[JSWolf]

Originally Posted by Sirtel

Because it can cause problems with word spacing when you read fully justified text. I never enable it for this reason. Good word spacing is far more important to me than ligatures.

But you also get kerning. After reading some KePub set this way, most displayed without a problem. Only one of the three KePub I read had a problem and that was just in one paragraph.

[beedaddy]

Thanks for your comments. I think everything is now sufficiently ok with regard to kerning and ligatures. I am really relieved to these with kepub.

(Perhaps someone has an idea regarding Bookerly and Litarata issues I have?)

[jackie_w]

Originally Posted by beedaddy

Thanks for your comments. I think everything is now sufficiently ok with regard to kerning and ligatures. I am really relieved to these with kepub.

(Perhaps someone has an idea regarding Bookerly and Litarata issues I have?)

The problem you're seeing with Bookerly is quite common with sideloaded fonts. Kobos are quite picky about some of the internal font metrics, specifically the Panose weight setting. You can fix your Bookerly ttfs with a font editor. See posts #2 and post #9 in this thread for details. The example shown in that thread is for Amazon's Ember font but you can use the same method to fix Bookerly.

[beedaddy]

Originally Posted by jackie_w

The problem you're seeing with Bookerly is quite common with sideloaded fonts. Kobos are quite picky about some of the internal font metrics, specifically the Panose weight setting. You can fix your Bookerly ttfs with a font editor. See posts #2 and post #9 in this thread for details. The example shown in that thread is for Amazon's Ember font but you can use the same method to fix Bookerly.

Perfect, that's exactly the solution. Thanks a lot!

[Sirtel]

Originally Posted by JSWolf

But you also get kerning. After reading some KePub set this way, most displayed without a problem. Only one of the three KePub I read had a problem and that was just in one paragraph.

Well, you use hyphenation, I don't and so every one of my kepubs has problems when kerning and ligatures are enabled.

[trekk]

Originally Posted by beedaddy

Thanks for your comments. I think everything is now sufficiently ok with regard to kerning and ligatures. I am really relieved to these with kepub.

(Perhaps someone has an idea regarding Bookerly and Litarata issues I have?)

You can try Literata Book. IIRC, you can set a smaller line-height with it.

[JSWolf]

Originally Posted by Sirtel

Well, you use hyphenation, I don't and so every one of my kepubs has problems when kerning and ligatures are enabled.

Hyphenation has nothing to do with kerning and ligatures. You can use OptimizeLegibility with left justified and no hyphenation.

[JSWolf]

Originally Posted by beedaddy

Thanks for your comments. I think everything is now sufficiently ok with regard to kerning and ligatures. I am really relieved to these with kepub.

(Perhaps someone has an idea regarding Bookerly and Litarata issues I have?)

You can try ChareInk. It has a small line height, kerning, and ligatures. You can get it at the following link. I suggest you get the hinted no-weight version for your Kobo.
https://www.mobileread.com/forums/sh...d.php?t=184056

[Sirtel]

Originally Posted by JSWolf

Hyphenation has nothing to do with kerning and ligatures. You can use OptimizeLegibility with left justified and no hyphenation.

Hyphenation has everything to do with word spacing. That's what I meant by saying you may not have those issues when you use OptimizeLegibility, but I certainly do. And no, I don't want to read left justified.

[Manrico]

Originally Posted by beedaddy

- Using Bookerly: Why is italic displayed as bold-italic? Am I doing something wrong with fonts import? I put the files Bookerly-Regular.ttf, Bookerly-Bold.ttf, Bookerly-BoldItalic.ttf and Bookerly-Italic.ttf in the fonts-directory. Is the naming wrong?

A "quick and dirty" solution to this problem is to put only the other three font files and not Bookerly-BoldItalic.ttf in the fonts directory. On my Libra the normal italic is then used - both for epub and kepub.

[beedaddy]

Originally Posted by trekk

You can try Literata Book. IIRC, you can set a smaller line-height with it.

Mh, but Literata Book is v2 and I would prefer v3. But I can also live with it as it is now.