Font size difference between ePub & kepub

[JSWolf]

What is the difference between a font size in ePub and a font size in kepub with no font size set in CSS and the both sliders set exactly the same? If I want to read kepub, I have to adjust the font size and then adjust it back. If I know the size difference, I can leave the slider and set the font size in kepub to compensate. Thanks.

[jackie_w]

Are you already using the 'Modify CSS' option in the calibre driver with a kobo_extra.css file on your H2O? If so, I found the easiest way to apply the font-size change is by adding an extra line to the kobo_extra.css file so it automatically gets added on-the-fly during send-to-device:

body>div#book-columns>div#book-inner {font-size:1.5em}

This works well on my H2O (and GloHD) and I don't need to keep changing the slider when I switch between epub and kepub. Surprisingly the KA1 'just works' without needing to do any kind of font-size adjustment.

[rashkae]

Depends on the device. One of them, (I think it was the A1, but I'm not sure) has almost identical font size between Epub and Kepub... others vary wildly.

[JSWolf]

Would it not be easier to just put the font size in body for the kepub?

I'm thinking of giving kepub another go, but only if I don't have to keep switching the font size.

[jackie_w]

Originally Posted by JSWolf

Would it not be easier to just put the font size in body for the kepub?

Well that depends as only you can decide what is 'easier'.

Are you planning to:

• Convert your epub to kepub in calibre and store both formats in the library. You've always expressed a dislike for unnecessary conversions.
• Hand edit every kepub CSS. Neither calibre Editor nor 'Unpack book' will open .kepub so you'll have to use another method.
• Use calibre send-to-device for transfer.

The way I suggested was:

• Create/edit existing kobo_extra.css (in Kobo root dir) once then forget about it. The addition I suggested will not interfere with your standard epubs if you plan to read a mix of epub and kepub.
• Use KoboTouchExtended driver with both 'Modify CSS' and 'Enable Extended Kobo features' checked to format-shift epub to kepub and scale up the font-size during send-to-device. Your calibre library remains uncluttered with kepubs and your master epub remains suitable for both Kobo and any other epub reading app you use.

The choice is yours

[JSWolf]

I was thinking of giving a try to kepubify to see how it goes. I can add extra CSS with kepubify. So I can can try your CSS and see how it goes.

[davidfor]

Originally Posted by jackie_w

• Hand edit every kepub CSS. Neither calibre Editor nor 'Unpack book' will open .kepub so you'll have to use another method.

If you are running calibre from source, solving that is a two line change.

[jackie_w]

Originally Posted by davidfor

If you are running calibre from source, solving that is a two line change.

Good to know should I ever find a need to use either of them regularly for kepubs.

I don't think JSWolf runs from source, though.

[JSWolf]

Would it be possible to add this as an option in the KoboTouchExtendedDriver? Thanks.

[A random blob]

Originally Posted by jackie_w

Well that depends as only you can decide what is 'easier'.

Are you planning to:

• Convert your epub to kepub in calibre and store both formats in the library. You've always expressed a dislike for unnecessary conversions.
• Hand edit every kepub CSS. Neither calibre Editor nor 'Unpack book' will open .kepub so you'll have to use another method.
• Use calibre send-to-device for transfer.

The way I suggested was:

• Create/edit existing kobo_extra.css (in Kobo root dir) once then forget about it. The addition I suggested will not interfere with your standard epubs if you plan to read a mix of epub and kepub.
• Use KoboTouchExtended driver with both 'Modify CSS' and 'Enable Extended Kobo features' checked to format-shift epub to kepub and scale up the font-size during send-to-device. Your calibre library remains uncluttered with kepubs and your master epub remains suitable for both Kobo and any other epub reading app you use.

The choice is yours

Hi Jackie! Sorry for quoting you after 2 years. I spent quite some time browsing the forum and trying to figure it out on my own in Calibre or using Kepubify, but I keep failing.

I wanted to do the hand edit thing, I'm fine with that. But I can't figure out how. The reader in question is Kobo Glo HD.

Which part did you mean to be hand edited?

The issue is the same like OP's. My kepub books fonts are at least 40% smaller than epubs.

Thanks

[jackie_w]

Originally Posted by A random blob

Hi Jackie! Sorry for quoting you after 2 years. I spent quite some time browsing the forum and trying to figure it out on my own in Calibre or using Kepubify, but I keep failing.

I wanted to do the hand edit thing, I'm fine with that. But I can't figure out how. The reader in question is Kobo Glo HD.

Which part did you mean to be hand edited?

The issue is the same like OP's. My kepub books fonts are at least 40% smaller than epubs.

There are 3 ways to do what you want. In all honesty I'd say the hand editing option is the one most like hard work and certainly not the one I'd recommend for an easy life in 2020.

But, as this is the option you're asking about ... You need to edit the CSS file(s) in your kepubs using whatever method you normally use. Append the following style rule to each one.

div#book-inner {
    font-size: 1.5em;
}

If your kepub has been created with calibre (KoboTouchExtended plugin or Kepub Output plugin) this should work reliably. 99.99999% of standard epubs would ignore this very specific style.

The method mentioned in the second half of my post that you quoted is far less effort if you're a calibre user. There's more detail on using a kobo_extra.css file here. You'd just need to add the above CSS rule to your kobo_extra.css file. The above style would then be automatically added to every CSS file of every epub and kepub sent to the Kobo via calibre without you having to do any manual editing.

The 3rd method of equalising font-size in kepubs & epubs, but only if you're a kobopatch user (or willing to become one) is to enable the patch named 'ePub uniform font scale'. If you do this you won't need to do any editing of CSS files because the font scale mismatch will be "fixed" in the firmware.

[A random blob]

Originally Posted by jackie_w

There are 3 ways to do what you want. In all honesty I'd say the hand editing option is the one most like hard work and certainly not the one I'd recommend for an easy life in 2020.

But, as this is the option you're asking about ... You need to edit the CSS file(s) in your kepubs using whatever method you normally use. Append the following style rule to each one.

div#book-inner {
    font-size: 1.5em;
}

If your kepub has been created with calibre (KoboTouchExtended plugin or Kepub Output plugin) this should work reliably. 99.99999% of standard epubs would ignore this very specific style.

The method mentioned in the second half of my post that you quoted is far less effort if you're a calibre user. There's more detail on using a kobo_extra.css here. You'd just need to add the above CSS rule to your kobo_extra.css file.

The 3rd method of equalising font-size in kepubs & epubs, but only if you're a kobopatch user (or willing to become one) is to enable the patch named 'ePub uniform font scale'. If you do this you won't need to do any editing of CSS files because the scale mismatch will be "fixed" in the firmware.

Hi Jackie. Thanks a lot for replying. In the end, I agree with you. You're right about the 2020 thing. I just patched the Kobo, and it's really nice. It's much faster, even though I ran into an ugly yellow tint issue and the UI is really bad compared to the one from 2017.

Will write later more about that.

Thanks a lot for the write-up on manual work, I'll use it for my old version Kobo

[JSWolf]

Originally Posted by A random blob

Hi Jackie. Thanks a lot for replying. In the end, I agree with you. You're right about the 2020 thing. I just patched the Kobo, and it's really nice. It's much faster, even though I ran into an ugly yellow tint issue and the UI is really bad compared to the one from 2017.

Will write later more about that.

Thanks a lot for the write-up on manual work, I'll use it for my old version Kobo

I think the UI is better then the UI from 2017. There are a lot more useful features with the current UI.