Why is the EPUB format so poorly implemented (on the desktop at least) ?

[Ortep]

Originally Posted by pdurrant

You would have thought so, wouldn't you? But that's not true. The different physical Kindles render Mobipocket files differently to each other, and Kindle for PC and Kindle for Mac render them differently again.

It's really very disappointing.

I don't care about small diffences. But if a mobi book is readable on my Kindle it is also readble on my wife's Bebook and our old Cybook.

That is not the case with ePub on the Bebook and the Cybook and my desktop. The horrible inplementations of ePub sometimes makes borders of 2 cm on one device and no borders at all on the other. Or one device has an indentation of one caracter at every paragraph while the other has something like half a line. Or an extra whilte line in between.

Or on one device everything looks OK while on the other al kinds of (inverted) ??? appear. Convert the file to mobi and most of your troubles are gone. Especially if you rip uit de CSS first.

I agrea that ePub is more sophisticated than Mobi. But everybody implements only 70% of the standard. And by preference an other 70% than the rest of the world.

The end result is that only 50% is common. That is why it looks often better if you rip out the CSS, then none of the fancy stuff that is rendered badly is available anymore.

Sigiel is only good for cutting a file in chapters, but that is something I have no need for unless the text of the file is OK.

Sometimes it works to convert the ePub with Calibre to RTF and edit all the fancy junk out with Word and the reconvert it.

[Toxaris]

If you say that Sigil is only good for cutting a file in chapters, you do it grave injustice. It has some flaws, sure. But in its right it is a very good tool to create epub's. And yes, without much problems your books look almost the same anywhere.

The examples you mention exactly proves my point. It is not the viewers that are at fault, but the creators of the epub's. They don't follow normal rules and you cannot expect that all viewers to adjust to all steps outside the format. Using pt or px instead of em for example.
Those things are quickly fixed. Much quicker than converting to mobi or RTF. I think it is funy that you remove 'junk' with Word and then reconvert it. There is even more junk in that way...

However, if it works for you.... But put the blame where it should be, the creators of the ePubs.

[DSpider]

You mean the creators/publishers don't put their ePubs through validators ? Because I think they do, and the files pass. Yet they still display differently on every system. Why is that ? Why can't they develop ONE, GOOD, reading engine and adapt it to multiple devices ? Or even use one already developed:

http://en.wikipedia.org/wiki/Gecko_%28layout_engine%29

Open source, cross platform... What are they, stupid ?

[theducks]

Originally Posted by DSpider

You mean the creators/publishers don't put their ePubs through validators ? Because I think they do, and the files pass. Yet they still display differently on every system. Why is that ? Why can't they develop ONE, GOOD, reading engine and adapt it to multiple devices ? Or even use one already developed:

http://en.wikipedia.org/wiki/Gecko_%28layout_engine%29

Open source, cross platform... What are they, stupid ?

A Valid Junk file just passed all the Syntax rules ..
Many have more bloat than a US Gov. budget
But all the i's have been dotted and t's crossed

The book can look like dog doo and pass the check

[Toxaris]

Indeed, validators only do so much. The engine you mention is not usable. The reason is simple. It is a browser engine, not an ePub engine.
Some specifications in the ePub format are not in a browser engine and vice versa.

They are not stupid, but just don't want to do it. Apparently it is not as simple as it seems.

I would not be surprised if some publishers do not use validators. Don't forget, most publishers are not that happy with e-books. It is an afterthought and the larger publishers would love to see it fail.
There are only two validators at present. The first one is epubcheck. Do a search on the forum. You can really pass garbage through that one without any comment.
The other one is FlightCrew. That one is better, but I can imagine that also through that one garbage can be validated.

If you create a 'normal' book, following the standards and best practices as can be found all around the forum, it will look almost the same on most readers. What do I mean with a 'normal' book? Simple: cover, TOC, headings, paragraphs (with or without indents), dropcaps perhaps, some images, simple formating, things like that. Should serve most books.
Where do problems arise? From what I have seen centering images, floats and more obscure options in CSS. By obscure I mean less used. The centering images is the most stupid one. That one happens on the i-devices and aldiko for sure.

As long as the reader supports CSS, it should look the same.

[Jellby]

Originally Posted by Toxaris

As long as the reader supports CSS, it should look the same.

Except that different readers may have different defaults, and support a different set of the standard CSS (some properties are "optional" in the spec, and it says that reading systems "may" do this or that).

[eping]

Originally Posted by DSpider

Yet they still display differently on every system. Why is that ? Why can't they develop ONE, GOOD, reading engine and adapt it to multiple devices ? Or even use one already developed:
http://en.wikipedia.org/wiki/Gecko_%28layout_engine%29
Open source, cross platform... What are they, stupid ?

I think the main reason is commercial.

1 Adobe fears ePub will encroach its benefit from PDF.
So they want to keep ePub only in the field of e-ink devices.

2 Microsoft continues their numbness on ebook market.
MS hasn't improved their CHM format for over ten years, actually
CHM is very similar to ePub.

3 ePub committee adopts XHTML instead of HTML.
This make desktop eReaders based on webbrowser meaningless.
For these Readers will show invalid XHTML as HTML correctly,
while such invalid XHTML in ePub will not show properly on eReader
devices.
It's not easy for desktop Readers to simulate the backwardness
of those ebook devices, especially ADE system.
So users will not accept a more robust epub reader on desktop.

4 Before Apple adopted ePub, ePub was unimpressive.
But Apple is not so influential on PC.

So ePub lacks a real leading giant till now.

[Toxaris]

Apple has not adopted ePub. They are trying to corrupt it. Instead of trying to change the format via the IDPF, the create their own version.
Sure, some changes are good, but there are also bad ones. Apple should call their version iPub or alike and should be forbidden to say they support/adopt ePub.

[Toxaris]

Originally Posted by Jellby

Except that different readers may have different defaults, and support a different set of the standard CSS (some properties are "optional" in the spec, and it says that reading systems "may" do this or that).

Agree, the specs are not perfect. However, the most used properties are implemented ok. The defaults, that is another question all together...