Why can't Calibre preserve ISBN-10 numbers?

[MelBr]

This has been bugging me for a white: Calibre removes/destroys ISBN-10 numbers for some reason after you download metadata.

For example, input an ISBN and as ISBN-10 and then fetch metadata. It will be replaced by ISBN-13 number and ISBN-10 will disappear forever. Why is that? Why can't Calibre preserve what the user has entered before? It's preserving all kinds of crap inside the IDs filed (URI, all kinds of useless URLs etc) but is erasing ISBNs.

Why doesn't it recognize ISBN-10 and ISBN-13 as fields since those are used on almost every book site out there (Amazon, B&N, iTunes etc)? It only recognizes "isbn:" field and fills it in with ISBN-13 numbers.

Anyone have some solutions to this problem?

[unboggling]

My first solution was to convert all ISBN10s to ISBN13s, for the sake of consistency.

A couple years later I realized I didn't care about ISBNs at all, and I stopped making sure I have good ISBNs. After initial metadata download having an ISBN is useless to me. ISBN10s, ISBN13s, no ISBN: why worry about it at all?

[JSWolf]

ISBN numbers are important for one reason... to make sure you have the correct version of the book. For example, on Goodreads, using the ISBN to search for the book you are reading is a good thing to do then you know you have the same version in your list as you are reading.

[At_Libitum]

Originally Posted by JSWolf

ISBN numbers are important for one reason... to make sure you have the correct version of the book. For example, on Goodreads, using the ISBN to search for the book you are reading is a good thing to do then you know you have the same version in your list as you are reading.

Since I concentrate mostly on the public domain most all of my epubs originate from sites as Archive.org, Gutenberg, Feedbooks, and the odd website. I've been wondering the same thing actually.

What _is_ the correct version?

I realize that when multiple editions exists there may be more than subtle differences between editions. But since my version is an electronic one, the only reason I add an isbn if I happen to find one is so I have a link to an online source of info about the story, which hardcover version that may be linked to is moot for me, so for me the value to link to a specific edition is mostly nill...

That the version I link to may not be the same version as I am reading is for me of less importance because the story is still the same one, be it packed in a different medium

[BetterRed]

What happens if one nominates an edition (publisher, pubdate) published prior to 2007 - ideally the ISDN-10 should take precedence because ISDN-13 didn't exist before Jan 1 2007.

BR

[MelBr]

Originally Posted by unboggling

My first solution was to convert all ISBN10s to ISBN13s, for the sake of consistency.

A couple years later I realized I didn't care about ISBNs at all, and I stopped making sure I have good ISBNs. After initial metadata download having an ISBN is useless to me. ISBN10s, ISBN13s, no ISBN: why worry about it at all?

Older books don't have ISBN-13 numbers even though Calibre manages to find them somehow since they were added to some books by publishers.

Problem is that if you open an older book, there is no ISBN-13 in it… only ISBN-10.

And I have problem with Calibre replacing data arbitrarily and not supporting ISO standard which specifies both ISBN-10 and ISBN-13 as standards.

[theducks]

Originally Posted by MelBr

Older books don't have ISBN-13 numbers even though Calibre manages to find them somehow since they were added to some books by publishers.

Problem is that if you open an older book, there is no ISBN-13 in it… only ISBN-10.

And I have problem with Calibre replacing data arbitrarily and not supporting ISO standard which specifies both ISBN-10 and ISBN-13 as standards.

In many cases ISBN 13 is just the Bookland code version
( http://en.wikipedia.org/wiki/Bookland ) of ISBN <-note it is just ISBN back then

ISBN 13 is just the representation of ISBN(10) for UPC/EAN scanning

[unboggling]

Originally Posted by MelBr

Older books don't have ISBN-13 numbers even though Calibre manages to find them somehow since they were added to some books by publishers.

Problem is that if you open an older book, there is no ISBN-13 in it… only ISBN-10.

And I have problem with Calibre replacing data arbitrarily and not supporting ISO standard which specifies both ISBN-10 and ISBN-13 as standards.

Regarding ISBN disappearing after metadata download, when that happened in the past I would Extract ISBN (optional plugin) from the book or copy/paste a good ISBN13 from a site such as ISFDB. For old classics or other public domain books without an ISBN I'd usually not worry about an ISBN.

[unboggling]

Originally Posted by BetterRed

What happens if one nominates an edition (publisher, pubdate) published prior to 2007 - ideally the ISDN-10 should take precedence because ISDN-13 didn't exist before Jan 1 2007.

BR

I preferred 13s anyway.
ISBN Converter at http://pcn.loc.gov/isbncnvt.html