PDF to MOBI and EPUB to MOBI

bob-e-reader · 06-07-2015, 05:15 PM

Hello,

Description of the problem:

Convert a PDF file (<6MB) to MOBI, size of MOBY converted is about 80MB
Delete the PDF file from Calibre (so I know the newt conversion will be made from the MOBI file)
Convert the converted MOBI file to EPUB, size of the EPUB is about 25MB
Delete the MOBI file from Calibre (so I know the newt conversion will be made from the EPUB file)
Convert the EPUB into a MOBI file, size of the MOBI is about 25MB.

Questions:

1) Is that normal that a small PDF file will become 40 bigger when converted to MOBI?
2) Why is there such a difference between PDF-->MOBI and MOBI-->EPUB-->MOBI conversions?

3) As I explained in the description, I delete files so I'm sure the conversion is made from a determined base file (MOBI instead of PDF for exemple).
Is there a way telling Calibre what file format to use when converting from, and having more formats of the same file?

Thanks

Notjohn · 06-08-2015, 05:30 AM

Working from PDF is always a bear. Is there no way you can go to a Word doc? Failing that, I'd prefer the nuclear option and render it as plain text, then reformat.

The entire text of A la recherche du temps perdu is available in a Kindle edition for less than 5MB. That's seven books, most of them on the long side, some so long they were originally published in two volumes. I think it's generally considered to be a million words in length.

(And before we despair of the quality of the American mind, note that the Scott Moncrieff translation is #9,489 Paid in Kindle Store!)

darryl · 06-08-2015, 05:47 AM

1. Yes. Anything can happen with a pdf. The results of conversion are usually far from satisfactory unless you are prepared to spend substantial time on editing.

2. There can be many factors that contribute to this. The three formats are very different. In the particular case you describe it may well be because of some peculiarity of the original pdf which does not convert well to mobi.

3. In the top left corner of the conversion screen there is a drop-down menu which lets you select the source format to convert from.

06-07-2015, 05:15 PM	#1
bob-e-reader Junior Member Posts: 1 Karma: 10 Join Date: Jun 2015 Device: Kindle 3	PDF to MOBI and EPUB to MOBI Hello, Description of the problem: Convert a PDF file (<6MB) to MOBI, size of MOBY converted is about 80MB Delete the PDF file from Calibre (so I know the newt conversion will be made from the MOBI file) Convert the converted MOBI file to EPUB, size of the EPUB is about 25MB Delete the MOBI file from Calibre (so I know the newt conversion will be made from the EPUB file) Convert the EPUB into a MOBI file, size of the MOBI is about 25MB. Questions: 1) Is that normal that a small PDF file will become 40 bigger when converted to MOBI? 2) Why is there such a difference between PDF-->MOBI and MOBI-->EPUB-->MOBI conversions? 3) As I explained in the description, I delete files so I'm sure the conversion is made from a determined base file (MOBI instead of PDF for exemple). Is there a way telling Calibre what file format to use when converting from, and having more formats of the same file? Thanks

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06-08-2015, 05:30 AM	#2
Notjohn mostly an observer Posts: 1,515 Karma: 987654 Join Date: Dec 2012 Device: Kindle	Working from PDF is always a bear. Is there no way you can go to a Word doc? Failing that, I'd prefer the nuclear option and render it as plain text, then reformat. The entire text of A la recherche du temps perdu is available in a Kindle edition for less than 5MB. That's seven books, most of them on the long side, some so long they were originally published in two volumes. I think it's generally considered to be a million words in length. (And before we despair of the quality of the American mind, note that the Scott Moncrieff translation is #9,489 Paid in Kindle Store!)

06-08-2015, 05:47 AM	#3
darryl Wizard Posts: 3,108 Karma: 60231510 Join Date: Nov 2011 Location: Australia Device: Kobo Aura H2O, Kindle Oasis, Huwei Ascend Mate 7	1. Yes. Anything can happen with a pdf. The results of conversion are usually far from satisfactory unless you are prepared to spend substantial time on editing. 2. There can be many factors that contribute to this. The three formats are very different. In the particular case you describe it may well be because of some peculiarity of the original pdf which does not convert well to mobi. 3. In the top left corner of the conversion screen there is a drop-down menu which lets you select the source format to convert from.

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