The procedure involves creating a well-formatted Kindle book first, and then converting it to epub using the free Calibre software.
First, you need to edit your HTML file (from the procedure above) to make some adjustments to the .epub format. Create a separate file folder for the Nook book and copy and paste all your .mobi book files (NCX, OPF, HTML, JPEG and all other files). I recommend creating this Nook book folder in the same location where your MobiPocket book directory is located and giving it the same name plus N at the end. Now you need to edit the new mpb_toc.html file (using Notepad) to correct the name of the directory in all HTML links (keep in mind that in HTML
references, %20 means a space, %5C a backward slash, and %3A is the code for the colon symbol “:”). If you used my HTML template for your Kindle book, you need to delete all extra line breaks after each heading in the HTML file of your prospective Nook book. In Microsoft Word, you can do this easily using the “Replace” feature, which can be found on the right-hand side of the “Home” ribbon in Word 2007 and 2010 or in the “Edit” menu (Word 2003 and earlier). How to use Word to edit your HTML file was described in detail above. In the “Replace” dialog box, type </h1><br> in the “Find what” field and </h1> in the “Replace with” field. Click “Replace all.” Do the same for the h2 tags. This operation is necessary because epub-converting software creates extra line breaks after each heading and you already have those in my HTML template. In a similar fashion, replace all occurrences of “color: windowtext” (without quotes) with “color: #084B8A” (without quotes). I also recommend replacing all occurrences of </p><br> with </p><br><br> because epub-converting software deletes all spaces between paragraphs if you have them in your book.
If you have internal links (cross-references) inside your book (aside from the Table of contents links) you may want to insert a friendly warning at the beginning of the book along the lines of: “Because currently there is no “go back” button in Nook reading applications, please remember your current page number before clicking on any link inside this ebook.” Strangely enough, Nook reading applications are not link-friendly at the time of this writing, although this may change in the future.
Now build the new .mobi file using KindleGen and your Nook files and select no compression (use the new file folder name and -c0 instead of -c1 in the command line).
Download and install the free Calibre software. Start the “Calibre – E-book management” application and press the “Add books” button. Navigate to the new version of the .mobi file in your Nook book directory and click “Open.” Calibre will import your ebook and add it to the Calibre library. After that, select your ebook in Calibre (single left-click) and press the “Convert books” button. By default Calibre will convert your book to the .epub format, exactly what you need for the Nook eReader. In the “Convert” dialog window, click the “Page Setup” tab and select “Nook” as your output format and “MobiPocket books” as your input format. Do not change any other settings. Click “OK.” Calibre will convert your .mobi book and place the .epub file (the finished NookBook file) in the same directory as your imported ebook files (depending on where you chose to place the “Calibre library” directory when you installed the software). The whole process can take several minutes depending on the size and complexity of your ebook. As soon as “Jobs: 1” changes to “Jobs: 0” in the lower right-hand corner of Calibre main window, you can go to the “Calibre library” folder and check out your .epub file. There are several things
you need to know about this conversion process:
1) Calibre automatically creates the NCX table of contents and you do not have to do anything yourself. This is good news. The bad news is that this NCX is based on and identical to the regular table of contents that you created in MobiPocket Creator awhile back. To be precise, the Calibre NCX contains navpoints corresponding exactly to all of the items in the mbp_toc.html file. If you created a custom NCX file that is different from your regular table of contents, this custom NCX will disappear from your .epub book file.
2) Be sure to check what your ebook looks like in the Nook for PC application. To do this, start “Nook for PC,” click on “My library” -> “My Stuff” -> “Add new item.” Then navigate to your .epub file in the dialog box. Now you can browse your book and check the formatting. Most likely you will have to edit your HTML file and rebuild the book many times until you achieve a nice format. If you close the Nook for PC application while your book file is open, it may produce an error message; this is normal and should not be a cause for concern (any software contains bugs). To delete this ebook from “My Stuff,” go to the “My Documents” folder on your PC, open the folder “My Barnes & Noble Books,” and delete the .epub file manually.
3) You can also check the formatting of your book in the Calibre eReader by pressing the “View” button in Calibre. The Calibre eReader contains a few bugs at the time of this writing and it does not match the appearance of your ebook on the Nook eReader exactly. You can also preview your book in some other software or by means of the “Preview” function on the Barnes & Noble self-publishing website after you upload your ebook for publication.
4) If you have a lot of internal links inside your book, make sure all of them work properly because Calibre may screw them up. (The nice thing about Calibre is that it is free; thank you, Kovid Goyal! But free software, in my view, tends to have more bugs than paid software.) Calibre breaks up your HTML file into many small HTML files, mostly using your page breaks for this purpose and also making sure that all files are less than 260KB. If you have h1 or h2 tags (headings) that are associated with named anchors (internal links), and if these headings are not preceded by a page break, then Calibre will create separate HTML files for the portions of the book corresponding to these headings and your anchors and headings may end up in different files. To prevent this problem, make sure that all headings and subheadings in your main HTML file are preceded by a page break (and make sure that a named anchor and its associated heading are not separated by a page break).
5) If a named anchor is located at the very end of a chapter (i.e., at the very end of a separate small HTML file created by Calibre), then the link associated with this anchor will not work well and will be pointing to a location several lines of text upstream of your anchor. To prevent this problem, you can insert approximately 30 line breaks (<br> tags) before each page break.
6) Calibre does not handle ordered and unordered lists well (the ol and ul tags in your HTML code). If you use a small font size for the HTML lists, Calibre will convert it to the normal size. Calibre also makes all lists left-aligned. You can either ignore these minor problems or you can do some tinkering with the conversion options and/or your HTML code.
7) The quality of the cover image created by Calibre is rather low and the dimensions are down-sized to 530x706 pixels. You can open the .epub file using the free 7-Zip software and replace the file with a good-quality image using the following approach. Resize your original JPEG cover image to the 600x730 pixel dimensions in your graphics editor (according to B&N, these are pixel dimensions of the Nook screen and the optimal cover size) and save it with good or best quality options (compression to 96-97% JPEG quality will produce an image about 250KB versus the Calibre cover at approximately 80KB). The size of your image file should be less than 260KB because some .epub reading software cannot handle large files. Change the name of your cover image file to “cover.jpeg” to match the name and extension of the .epub cover file. Delete the cover image from the .epub file while it is open in 7-Zip and then drag and drop your good-quality cover image to replace the deleted file.
8) The double conversion process (from .html to .mobi and then from .mobi to .epub) will significantly reduce quality of the images inside your book, if you have any. For example, if you started with a JPEG file at 35KB before creating a .mobi file, you may find that the final image file inside the .epub file is only about 5KB (!). If you open your .epub file in 7-Zip, all of your interior images are located inside the “images” folder. They are named consecutively 00001.jpg, 00002.jpg, and so on. You can extract those images to your desktop to see which file is which image and you can replace them all with good-quality images as described above for the cover image (making sure that file names and extensions exactly match the image files you are replacing inside the .epub file).
You are all set. After your .epub book is ready, you can go to the PubIt! website, create an account (if you do not have a Barnes & Noble account) and then set up your NookBook for sale on the Barnes & Noble website. You will see most of the same options as you have on the Amazon’s KDP website. For example, you can select digital rights management (DRM-protection) for your book and enter book description, list price, select a category, etc. The PubIt! platform requires you to enter the name of the publisher, and you can either use your own name or simply enter “PubIt.” After you fill out all fields, upload and preview your book, you can click the “Put on sale” button, and your ebook will appear on the Barnes & Noble website within one to two weeks. Although the description states that the publication process takes 24-72 hours, in reality it often takes longer, and you shouldn’t get worried if the web page of your ebook does not appear on the B&N website after 3 days.
Be advised that if you enter editorial reviews on the detail page of your NookBook, the field “Where Review Was Published” does not work and whatever you put in there will not be shown on the web page of your NookBook. On the other hand, the first and last name of the reviewer will be displayed successfully. If this is the very first time you are entering an editorial review for your NookBook, you can enter both the first and last name of the reviewer in the field “First Name” and the name of the source (e.g., “The Library Journal”) in the field “Last Name.” This way, both the reviewer’s name and where the review was published will be displayed successfully. If the editorial reviews have already been published on the B&N web page of your ebook and the review source is not displayed (because you used the field “Where Review Was Published”), then there is nothing you can do, aside from trying to contact email@example.com asking them for help.