Problems in lit to epub conversion

[carpler]

I'm a newbie with ebooks and related, but there is something frustrating for me in conversion.
I've got a Nook STR and I've tried several times to convert some ebook to epub, but always with some issue.
The input format that I used was: pdf, rtf and lit, but never the epub outup had the same aspect as the original.
Why this?
Sometimes I've got pagebreak where is not, the images with used as initial letter is not alligned as the original, and so on.
Initially I thought about a pdf problem, but I did not expect the same problems for the lit format.
Why is so difficult convert files and obtain the same aspect?
Wich is the best input format to voncert in epub?
Ah: I use Calibre 0.8.17.
Many thanks for your attention

[user_none]

Due to differences in formats there is no way to produce an exact looking output from an arbitrary input with an automated conversion. If you're unhappy with the output of a conversion I recommend you either try it again with different options or use a tool like Sigil to edit the EPUB to your liking.

[jjabrams]

Originally Posted by carpler

Why is so difficult convert files and obtain the same aspect?
Wich is the best input format to convert in epub?

I've found that straight up html works well. If you don't have a lot of html know how, you can try uploading the book into "mobi pocket creator" to get a .prc book and then upload that to Calibre. There are still going to be a few issues if the html is not to Calibre's standards, but you may get better results.

Hope this helped a little

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