Clara Standard books epub vs kepub and calibre

[Inquisitive_Ram]

I am thinking of switching from my paperwhite to a clara HD

I have a bunch of epubs in calibre

Standard ebooks say that for kobo one should use their kepub files rather than epub files because "[although] Kobos can open and read regular epub files like the compatible epubs we offer for download..... doing so triggers Kobo’s bad ebook renderer, which is based on A.D.E"

https://standardebooks.org/help/how-...books#kobo-faq

However, in calibre you can set it up so that epubs in calibre convert to kepub on sending to the Kobo reader.

So my question is whether there is much material difference between
a) sending a (well formatted) epub file to the Kobo via Calibre which converts to kepub)
b) reimporting the books as kepubs from standard books and then sending them to the Kobo (via calibre)

[Quoth]

No, I only read the regular epubs on my Kobo. I don't like kepubs. I do convert all imported epubs from Standard ebooks and Gutenberg to epub with some settings set.
Reading one right now.
Kepubs have advantage of able to zoom images. It's a matter of opinion if rendering is better. There are bugs in kepub renderer. An epub from docx looks like original (if on a small page size) in Wordprocessor, a kepub doesn't.

[JSWolf]

Standard Ebooks makes their ePub such that it breaks with RMSDK on Kobo. Do they have to do it this way? Nope. Do they have to make their ePub as complicated (code wise) as possible? Nope.

But they do. It's been pointed out to them what's wrong and how to fix it. Also, it's been shown to them that the same eBooks can be made with simple code. But they don't care and refuse to do it so there ePub works in more places.

So what I do is refuse to have anything to do with their eBooks. There should be no need to have to do a Calibre ePub > ePub conversion. They refuse to listen to reason, I refuse to recommend them to anyone.

[rashkae]

Originally Posted by Inquisitive_Ram

"doing so triggers Kobo’s bad ebook renderer, which is based on A.D.E"

As you've seen, calling Kobo's e-pub renderer 'bad' is a hot take. The two engines are different, each with their pros and cons and unique bag of bugs. Personally, I only use Kepub on my reader, but ironically, the general consensus is that ADE has better typography. In the end, this will be a matter of personal preference.

I don't think it's right to blame Standard E-books for the incompatibility, however. If their e-books are standard compliant, and it is Adobe/Kobo who refuse to fix bugs that causes the formatting to fail, it's clearly a fault with Adobe/Kobo.

So my question is whether there is much material difference between
a) sending a (well formatted) epub file to the Kobo via Calibre which converts to kepub)
b) reimporting the books as kepubs from standard books and then sending them to the Kobo (via calibre)

There really isn't much difference between epub and kepub. Only the addition of <span> elements within the text without any formatting changes. (The resulting Kepub is itself, a standard e-pub that can be properly and completely read with any epub reading software.)

That being said, it's possible that Standard E-books might be making more changes to accommodate the Kobo's quirks. For example, the Kepub engine can not properly render spacing or sizes in physical measurements, (ie, Inches, cm, or pt.) and only produces consistent results if using relative sizes, (em or %)

[issybird]

Originally Posted by JSWolf

So what I do is refuse to have anything to do with their eBooks. There should be no need to have to do a Calibre ePub > ePub conversion. They refuse to listen to reason, I refuse to recommend them to anyone.

That'll show 'em!

[Quoth]

Also many ebooks use pt, because Wordprocessors don't use em. All correctly rendering engines simply regard 12pt = 1em, thus everything is relative as intended. The purely Kobo proprietary kepub doesn't do this with pt, which is a bug. I've not figured out exactly what it was doing and kepub may treat pt on margins and font sizes differently, so I gave up and switched to epub for Kobo. All ebooks then have relative font sizes and margins as intended, no matter if pt or em.

However you have a choice. I now convert all ebooks added to Calibre anyway to automatically remove line-height and other stupidity. Sometimes I have to manually fix azw3, but only from the house of random penguins. So I have no problem with Standard eBooks epubs.

Calibre gives choice. It quick and trivial to have epub or automatically send kepub to a Kobo, so the same epub is sent as epub to Sony, Boyue, Apps, Y-ben, Binatone etc. I copy a load of PD ebooks to other family members. Not all have Kobos and some get azw3.

[JSWolf]

Originally Posted by Quoth

Also many ebooks use pt, because Wordprocessors don't use em. All correctly rendering engines simply regard 12pt = 1em, thus everything is relative as intended. The purely Kobo proprietary kepub doesn't do this with pt, which is a bug. I've not figured out exactly what it was doing and kepub may treat pt on margins and font sizes differently, so I gave up and switched to epub for Kobo. All ebooks then have relative font sizes and margins as intended, no matter if pt or em.

However you have a choice. I now convert all ebooks added to Calibre anyway to automatically remove line-height and other stupidity. Sometimes I have to manually fix azw3, but only from the house of random penguins. So I have no problem with Standard eBooks epubs.

Calibre gives choice. It quick and trivial to have epub or automatically send kepub to a Kobo, so the same epub is sent as epub to Sony, Boyue, Apps, Y-ben, Binatone etc. I copy a load of PD ebooks to other family members. Not all have Kobos and some get azw3.

The problem with Standard Ebooks and Kobo with ePub is that because of the way they do their ePub, the CSS is taken as having an error and the entire CSS is ignored.

[ZodWallop]

I download ePubs from StandardEbooks and use Calibre to send it as a kepub. I would have no problem downloading Standard's kepub, but since a kepub is just an ePub with extra spans, I like having the 'cleaner' ePub in my Calibre library.

[Inquisitive_Ram]

Thank you for comments everyone

I notice that when kepubs are imported into calibre, calibre regards them as epubs in terms of filetype

My calibre is setup to convert epubs to kepubs when sending to kobo

So when a kepub in calibre gets sent to Kobo, does calibre try and modify it again or does it recognise it is a kepub and then just pass it across? (I know I can always sideload the kepub to Kobo but I was just wondering)

[JSWolf]

Originally Posted by ZodWallop

I download ePubs from StandardEbooks and use Calibre to send it as a kepub. I would have no problem downloading Standard's kepub, but since a kepub is just an ePub with extra spans, I like having the 'cleaner' ePub in my Calibre library.

The ePub from Standard eBooks is very much not clean.

[ZodWallop]

Originally Posted by JSWolf

The ePub from Standard eBooks is very much not clean.

Thank you for your opinion.

[Cactus Chef]

As someone who was too young to have participated in the vim vs emacs wars of yesteryear, I am thrilled to be present to witness the EPUB vs KEPUB wars of today. Thank-you, internet!

Staying on topic, though:

Originally Posted by Inquisitive_Ram

So my question is whether there is much material difference between
a) sending a (well formatted) epub file to the Kobo via Calibre which converts to kepub)
b) reimporting the books as kepubs from standard books and then sending them to the Kobo (via calibre)

Having tried both, for the average user I really don't think there's much of a difference. I tend to stick with KEPUBs, but YMMV.

Also, unless you have a compelling reason to have SE books in your Calibre library, you could just download the books directly from SE onto your Kobo using the experimental browser. Since my Calibre library was meant to be a reflection of ebooks I had "bought" and stripped the DRM from, I stopped bothering to keep local copies of SE books.

[Sirtel]

Originally Posted by Cactus Chef

As someone who was too young to have participated in the vim vs emacs wars of yesteryear, I am thrilled to be present to witness the EPUB vs KEPUB wars of today. Thank-you, internet!

Yeah, this is history in the making. We live in exciting times indeed!

[Aleron Ives]

Originally Posted by ZodWallop

I would have no problem downloading Standard's kepub, but since a kepub is just an ePub with extra spans, I like having the 'cleaner' ePub in my Calibre library.

Are the pre-made KEPUB files the same as the ones you get with Calibre/kepubify, or does SE do extra processing on them?

[DNSB]

Originally Posted by Aleron Ives

Are the pre-made KEPUB files the same as the ones you get with Calibre/kepubify, or does SE do extra processing on them?

They are pretty much what you would get with the KTE driver or kepubify. They are intended for Kobo's epub3 Webkit based renderer so do not have a toc.ncx which will cause issues if you try reading on an epub2 renderer.