Can I convert Epub 3.0 to 2.0?

[DiapDealer]

Originally Posted by JSWolf

These eBooks do not need any ePub 3 specific features. Making them ePub 3 is silly. It just causes code bloat. i prefer to have the simplest code possible to do the job.

Not really true at all. The "do not need any epub3 features" mantra that epub3 haters cling to isn't really relevant. There's no only books that have audio/video/javascript should be epub3s rule. There's nothing inherently "silly" about a non-multimedia epub3. And non-multimedia epub3s are no more or less inherently "bloated" than their epub2 counterparts. In fact, there are many ways an epub3's code/css can be more efficient and simplistic than an epub2's

You don't have to like epub3, Jon. You just have to stop spreading untruths about it here. Your dogmatic dismissal of all things epub3 is what's getting silly (and very tiring). Take it somewhere else, please. Sigil supports the creation and editing of epub3. Deal with it.

[DiapDealer]

Originally Posted by stumped

It's been a while but I am pretty sure it would not let me delete a specific xhtml file from the left hand list, while in epub3, and the error message was something about operation not allowed.

Ah yes. That would be the nav document. It's required in an epub3. As such, it cannot be deleted (any more than the content.opf can be deleted). The nav document is identified by manifest properties in the opf. It could have any kind of name whatsoever in the Book Browser.

When using Sigil's ToC editing tools, it's the ncx being modified when in an epub2. But those same tools modify the nav document when editing an epub3.

[stumped]

Originally Posted by DiapDealer

Ah yes. That would be the nav document. It's required in an epub3. As such, it cannot be deleted (any more than the content.opf can be deleted). The nav document is identified by manifest properties in the opf. It could have any kind of name whatsoever in the Book Browser.

When using Sigil's ToC editing tools, it's the ncx being modified when in an epub2. But those same tools modify the nav document when editing an epub3.

ok - mark it down to my lack of epub3 knowledge then. I just assume that anything toc-looking near the top of the xhtml list is some inline version of the real toc so I habitually zap all such & tell sigil to generate a "proper" one if necessary
as for Js converting TO epub3 is silly comment, one reason I have seen posted (maybe by you) is that it facilitates use of the Bookari epub3 reader

[DiapDealer]

Originally Posted by stumped

as for Js converting TO epub3 is silly comment, one reason I have seen posted (maybe by you) is that it facilitates use of the Bookari epub3 reader

Quite possibly me. I know I've mentioned it before. I'm a convert. I read and archive my library in epub3 these days. I see no good reason not to. All my favorite software natively supports it.

[Toxaris]

The foot-/endnote method from ePUB3 is not really compatible with ePUB2. For me that would be a no-go.

[Doitsu]

Originally Posted by Toxaris

The foot-/endnote method from ePUB3 is not really compatible with ePUB2. For me that would be a no-go.

Theoretically, epub2 apps should ignore epub3-specific footnote attributes.

Did you encounter any specific problems with the epub3 footnote syntax with epub2 apps?

BTW, some time ago a created an epub3 test file with several different footnote flavors that worked fine even with ADE 1.7.

[jackie_w]

Originally Posted by DiapDealer

I prefer the EPUB3 renderer in the Bookari reading app...

I'd be interested to hear your opinions about the benefits of the Bookari EPUB3 renderer. I did try it when it was first announced but the app crashed with the first book I tried so I've avoided it ever since. I'd hate to be missing out on Good Stuff

[stumped]

I am also curious. If I make the effort to learn how to change epub 2 to 3 then open with bookari epub 3 renderer , what benefits can I expect. For reading a typical novel, not a fancy footnoted academic work .?

[DiapDealer]

There's nothing really mind-blowing about the benefits of the EPUB3 renderer in Bookari. It's a combination of things, actually.

For one thing, the EPUB3 renderer has more finely graduated font sizes--unlike the EPUB2 renderer where I invariably get to the point where one size is way too small and the next step is way too big, and there's no in between.

Another reason I've switched to primarily EPUB3 is the subject of this very thread. Converting my purchased EPUB3s (and I'm getting more and more EPUB3s when I buy books) is a pain in the butt, and takes time that could be better used reading. So is maintaining two themes (one for reading EPUB2s and one for EPUB3s). Never mind that sometimes I just want to download the ADE-encrypted EPUB3 books and read them immediately without tweaking them. Bookari allows me to do this.

Long story short: I want to read (and archive) one or the other standard (so I don't have to keep multiple setups and switch between them to read my books). And converting EPUB2s to EPUB3 is vastly easier (and quicker) than the other way round.

Only one standard being archived in my library + one theme/app to read them all with + finer font-size granularity + more time spent reading as opposed to converting/tweaking = EPUB3 for me. Making sure everything is EPUB3 is easier and takes less time than making sure everything is EPUB2 ever did. I wised up.

[SigilBear]

Originally Posted by stumped

I did it simply by running an epub to epub conversion in calibre.
epub3 IN, epub2 OUT, easy peasy, all on default settings
{ because I could not perform some sigil edit in an epub 3 source, I tried the above & it worked 1st time. I was able to edit the output file which sigil reported as being epub 2 }

Great tip; I was just going to ask about converting 2.0 to 3.0. I would think it would be easier than the other way around, because 2.0 probably doesn't have anything 3.0 can't handle.

[SigilBear]

Wow, informative thread. Now that I've changed my project to Epub 2.0, DiapDealer has almost talked me into switching back to 3.0.

I would assume Epub 3.0 is increasing in popularity and will probably become the default epub in the next few years, right? Or is Epub 3.0 so bad that some people are simply skipping it, waiting for Epub 4.0?

[Toxaris]

Originally Posted by SigilBear

Wow, informative thread. Now that I've changed my project to Epub 2.0, DiapDealer has almost talked me into switching back to 3.0.

I would assume Epub 3.0 is increasing in popularity and will probably become the default epub in the next few years, right? Or is Epub 3.0 so bad that some people are simply skipping it, waiting for Epub 4.0?

Well, I will personally skip ePUB3 for now still. For me it has no benefit at all, my reader does not support it. There are several flaws in the specifications of ePUB3 and they solve a lot of them in the new proposed format. However, that means that several things introduced in ePUB3 are thrown out again. This will lead to another non-compatible format.

[DiapDealer]

For the record: I'm not trying to get anyone to follow my lead. I don't really care if people ever fully embrace EPUB3 or not, to be perfectly frank. I just get tired of some of the "EPUB3 is the devil! It has no place in our eWorld!" attitudes expressed every time the topic comes up (I don't mean you @Tox). And I tire of the spread of unnecessary FUD surrounding EPUB3 as well.

The fact is: commercial EPUB3s are being sold by Kobo, B&N, Google Play Books, iBooks; and EPUB3s are being used as source for Kindlebooks. So there's no lack of device/app support for EPUB3. It's being "embraced" already. Maybe all the multi-media bells and whistles and features provided by html5/css3 aren't being supported, but who cares? They don't have to be utilized. It's not like every feature the standard allows needs to be used in every ebook in order to justify the standard's existence. Most ebooks don't leverage all that EPUB2 has to offer, either.

Use what you use/make what you make. At this point, open standards are just being turned into source code for other proprietary formats anyway.

[JustinThought]

Originally Posted by DiapDealer

Actually, no they're not "correct". A fairly decent chunk of the commercial epubs i buy and read these days are epub3.

//snip!//

There seems to be a big difference of opinion here. Some love 3.0, others seem to be...ummm, let's just say, a little less enthusiastic.

Is there any real advantage to using 3.0? I create all my epubs in 2.0, and don't seem to have any problems--even with those epubs I use with audio and even sometimes video files--although it does give both epubcheck and flightcrew a bit of a nervous moment. The files still work fine on my tablet with Moon+ reader, and my computer with Calibre. And since they're only for my own use, and won't be published, I don't see any conflict here.

Still, if my broadening my horizons and jumping headfirst into the 3.0 world would be beneficial, I'm willing to give it a shot. What say ye?

[DiapDealer]

Originally Posted by JustinThought

Is there any real advantage to using 3.0? I create all my epubs in 2.0, and don't seem to have any problems--even with those epubs I use with audio and even sometimes video files--although it does give both epubcheck and flightcrew a bit of a nervous moment. The files still work fine on my tablet with Moon+ reader, and my computer with Calibre. And since they're only for my own use, and won't be published, I don't see any conflict here.

Still, if my broadening my horizons and jumping headfirst into the 3.0 world would be beneficial, I'm willing to give it a shot. What say ye?

There's no advantage other than preference in my opinion (especially with your given scenario). In my situation, however, it's more a matter of; "my preferred ebook retailer offers this in EPUB3 and I don't really want to shop somewhere else -- and I don't want to perform a tedious EPUB3ectomy on it before I read it." And since I prefer to archive my library in a single format. I choose the one that requires less effort/time for me to purchase, read and archive. That's EPUB3 for me. Hands down.