azw3 versus epub question

[rjwse@aol.com]

I have been using epub format exclusively in the tag editor. When uploading an epub file to Amazon's application Kindle Previewer the epub file is converted to their proprietary format so you can read it on the Kindle Previewer application.
However, calibre has a converter which will convert epub to azw3. The resulting file is called kf8. I would have thought that the purpose of the file being converted from epub to azw3 would be to let you load this file into the Kindle Previewer application so that it does not require conversion from epub to the proprietary format. But, Kindle Previewer does not accept uploading of the calibre-converted azw3, while it will accept the calibre epub file. Am I missing something? Best regards, Pop

[jhowell]

The main purpose of conversion to KF8 (AZW3) format in calibre is so that the resulting file can be sideloaded to Kindle devices for reading. KF8 is a good format for that purpose because it is more functional than the older MOBI format and is supported by almost all Kindle apps and devices.

The Kindle Previewer is a tool for publishers. Its primary purpose to to convert from the primary e-book intake format (EPUB) to Amazon's latest format used by newer Kindles (KFX) and display the results so that problems can be found and corrected.

[Quoth]

And real eink Kindles preview azw3 better than Kindle Previewer. So we never use it now.
We convert the epub to mobi and azw3 in Calibre and check on 3 models of Kindle when the epub file has been checked and viewed. The epub gets uploaded to Amazon.

We might verify newly used styles by downloading published ebook to 3 Kindle models, which automatically gives mobi or azw3 on Download for USB and KFX only via Whispernet and only on one model Kindle. Amazon's KDP to arbitary Kindle model conversion of epub isn't the same as the Previer. You ought to be able to pick any model of Kindle in the Previewer and get an accurate simulation; you can't so it's useless even if you have no real kindles, because it's only similar.

[rjwse@aol.com]

Thanks to you both (Quoth and Howell) for reply and explanation. I am, in fact, uploading to KDP's 'Book Preview' then 'Launch Previewer'. Doing so is tedious, so I downloaded their self-sufficient app, but am hampered that I use Linux. I did download it and used it in Windows to evaluate epubs in progress. Bit by bit I chip away at it. Now I'm stuck on a few things here and there: 3em dash shows up as little square, meaning (I suppose) that it won't take unicode or something. Thanks again, Pop

[Quoth]

Only use regular hyphen for something like fish-like. Or it might be instead of to such as: 1851 - 1873
USA and other places have two schemes for dashes using asides instead of round brackets or commas.
1. USA em dash—with no spaces
2. Many other places use en dash – with spaces
In both cases they only come in pairs, except if the aside is at the end of a sentence. Same rule as commas used as ( and ), except you always have a closing bracket even at the end of a sentence.
Both USA and elsewhere use em dash for both broken off speech (no spaces) “Watch out for mar—” He fell down the stairs after stepping on a marble.
Both USA and elsewhere use an em dash for attribution.

—Rudyard Kipling

Often but not always as above, but may be on same line —Quoth

Other sorts of dash exist, like the minus (only used in formula). Any other sort of dash should only be on paper or PDF and only specialist use (though I can't think of it).

There are two problems with less used unicode characters:
1) The default app or ereader font may not support it.
2) A user might not select an embedded font, also some apps and mobi don't support embedded fonts at all.

Summary
Never use special em dashes. Only —

Similarly special widths of spaces are recommended on paper between figures and units such as 5 lbs or 9 kg, but just use only a regular space in ebooks.
Also turn off hyphenation on source wordpocessor for ebook source and only have hypenation on version for PDF. Don't add soft hyphens. Let the user/eReader do hyphenation or not.

[Quoth]

I switched from Windows to Linux entirely in Jan 2017, so now only have a Windows VM I never use. Since neither the KDP preview download, nor Kindle Previewer are "reliable" or "accurate", it's no loss. I earlier described the more reliable ways of checking.

[rjwse@aol.com]

Thanks for input. I was under the (apparently false) impression that Amazon's downloadable tester was a good final arbiter of epub composition for their own physical ebook readers. I am breaking rules using 3em for other things such as

<div style="text-align:center; font-weight:bold ;">⸻ scene ⸻</div>

I also use it for parts of long arrows.
Best regards, Pop

[Quoth]

>———<
Three regular em dashes.

I was under the (apparently false) impression that Amazon's downloadable tester was a good final arbiter of epub composition for their own physical ebook readers.

They suggest that but long time formatters of ebooks don't believe it and test on physical eink and if trying something new they double check by downloading the published version from Amazon (no need to download published versions from Smashwords/D2D who forward epubs also to Apple, Kobo, Barnes&Noble etc) or from Google's playstore.
Of course some epub apps are rubbish. We do test on ones that respect CSS.

That example won't work on lots of ereaders.

[nabsltd]

Originally Posted by Quoth

And real eink Kindles preview azw3 better than Kindle Previewer.

I haven't found any way at all to get Kindle Previewer to not show the KFX version. Every ePub I drag and drop shows that "Enhanced Typesetting" is enabled.

The docs for KP say that only KFX, MOBI, and AZK (for older iOS devices) are supported as output formats. But, since it also claims that AZW3 is supported as an input format, when it isn't unless the AZW3 contains a proper mobi7 folder, the docs may not be 100% accurate.

I'd love to have a way to access Amazon-supplied code for ePub to KF8 on my local machine.

[nabsltd]

Originally Posted by Quoth

Only use regular hyphen for something like fish-like. Or it might be instead of to such as: 1851 - 1873

Other sorts of dash exist, like the minus (only used in formula). Any other sort of dash should only be on paper or PDF and only specialist use (though I can't think of it).

A figure dash (‒) is the proper way to separate any sort of range (numbers, months, days of the week, etc.). So, your example would be:

1851-1873 (hyphen)
1851 - 1873 (hyphen with spaces)
1851‒1873 (figure dash)

In many fonts, a figure dash is slightly longer than an en-dash, but in some it is the same, or at least close enough that you can't see any difference.

[jhowell]

Originally Posted by nabsltd

I haven't found any way at all to get Kindle Previewer to not show the KFX version. Every ePub I drag and drop shows that "Enhanced Typesetting" is enabled.

You can use an older version of Kindle Previewer that predates KFX. That will show how KF8 and MOBI render on older Kindle devices very accurately.

I use version 2.94 from December 2014. It can be installed without impacting an already installed 3.x version. It can be downloaded from the Internet Archive: Windows or Mac.

Originally Posted by nabsltd

The docs for KP say that only KFX, MOBI, and AZK (for older iOS devices) are supported as output formats.

Kindle Previewer 3 can export multiple formats. When you use File, Export it defaults to exporting in KPF format but you can change the file type to MOBI or AZK instead in the dialog.

Originally Posted by nabsltd

I'd love to have a way to access Amazon-supplied code for ePub to KF8 on my local machine.

The Kindle Previewer can export a Master MOBI that contains KF8. That will work fine if you don't mind a bit of wasted storage.

The Previewer also includes the kindlegen program that you can run from the command line to create MOBI files.

[Quoth]

Originally Posted by nabsltd

A figure dash (‒) is the proper way to separate any sort of range (numbers, months, days of the week, etc.).

On PDFs for paper. Don't use it on ebooks.