Images in Ebooks
There are two types of EPUB Ebooks: Standard Layout, that allow text to re-flow and Fixed Layout where the page layouts are fixed and text does NOT re-flow.
Standard Layout is used for books that are mostly text and they may have images embedded between paragraphs, or on separate pages. This is the format that is most widely used and is compatible with the widest range of Reading devices.
Fixed Layout is used when: you need to have a background colour or to wrap text around images; if your pages have aspect ratios that you don’t want to change or if you want to have horizontal orientation or columns of text.
For most fiction books and many non-fiction books the Standard Layout is fine and I will only address that format here.
Different Ebook retailers have different guidelines regarding images and you need to read these if you want your images to appear correctly. However, there are some general guidelines that will help you avoid some common pitfalls and avoid rejection of your file.
Save all your photos and graphics “.png” or “.jpg”. You also need to ensure that images use Images the ‘RGB” colour space, not CMYK. If you use Photoshop or some other image editor you will be able to check the file and make any change there.
Replace all spaces in the image filename with underlines, or eliminate the spaces completely. Spaces in the filename can cause rejection when using EpubCheck. The operating systems in E-readers are not consistent in how they read spaces and the spaces can affect how your book displays.
Example: instead of “photo 21.jpg” use “photo_21jpg” or “photo21.jpg.”
To make your images/pictures searchable, include that there is a text description of your picture below the image as well as above. The image may appear on a separate page and still needs to be identified for the reader.
Avoid wrapping text around images. Use in-line images with text above and below for best results.
Tables and Diagrams
You need to convert Tables, Pie charts, etc. into images but make sure to test your Ebook to make sure that the .jpg or .png files are large enough to be read but not too large. Remember that once converted to an image file the fonts in the table or diagram will not resize if the reader changes font size.
Originally all images were set to a resolution of 72ppi, the same resolution that is used for the majority of internet images. In recent years, the resolution of E-readers has increased and Ebooks are also being read on high resolution devices such as Tablets, Phones, and high resolution computer screens such as the Retina. Many web-photos are now set at 96 ppi instead of the older 72 ppi standard.
If you want your images to look good on a wider range of devices the best option today is to save them at 150ppi. This is compromise between quality and size because we still need to keep the size of the file as small as possible for a few important reasons.
- Smaller downloads are more friendly for your customer.
- You may have an additional charge from your E-retailer when your customer downloads a large file. Amazon charges per MB downloaded.
- Some E-retailers have limits on upload filesizes.
If you have a large number of colour photographs your file-size can be quite large. In this case you can always revert to 72ppi OR convert your original files to greyscale. Both of these will have a significant effect of file-size.
Most conversation software will give you an option for the Resolution of your images and you can see it there. If you are making your own conversion you can test higher or lower settings to see the file-size you get.
Adjusting and Resizing your images
Your images may come from a number of sources and are likely to come in different sizes and resolutions. If you want to get the best results in the final Ebook you need to do some work on the photos in Photoshop, or some other image editing software.
Whatever you do, DO NOT just drag or copy an image directly into Word and then resize it using the resize handles on the image. All this does is to change the apparent size. The image document dimensions DO NOT CHANGE! This can cause all sorts of problems when converting to Ebook if the original is too big.
Make all your image adjustments OUTSIDE of Word and then place the images in Word. Apart from avoiding size problems, will get a much better feel for how the reader will see the picture in the final book.
The best time to adjust resolution is also BEFORE placing them in your document. Make the changes when you are editing your photos. This gives you a chance to check that images do not have very high resolution. Sometimes scans are made at 600 or 1200 ppi and these need to be adjusted for size and resolution before placing. Make sure that none of the images are set to more than 300 ppi. Anything above that is just a waste of space for Ebooks.
A good guideline for full-page images is to keep them under 590 pixels wide (under 500 pixels for Smashwords) and under 750 pixels high. This will give them a better chance of being displayed properly on most devices. If you are planning to have an image displayed between paragraphs, so that you get a mix of text and image on the same page it is best to keep the height dimensions under 300 pixels so that there is still space for around half a page of text either above or below the image.
Ebooks will have page breaks wherever needed based on both the screen size and orientation and on the user settings for font size and spacing. Your images may appear where you don’t expect them, at the top or bottom of a page or isolated on a single page. The quality of the image will also depend on the specific device used. Keep this in mind when selecting your images. If very fine detail is important to your image it may be lost on a low resolution E-Ink screen. If some fine content is important use a zoomed-in photo to show it or describe it fully in the text.
Whatever word processor you use for writing beware of using “floating” images. If you do this the image is not anchored and may not appear where you want it to be. You need to Anchor images. To check if an image is “floating” click on the image and try to drag it. If it can be dragged to a new position it is floating.
To anchor images, right click on the image, then click “Format / Picture / Layout”, and select “In Line With Text”. When you have saved this setting you can then centre the image using your already prepared “Centred” style. When you do this, your photo will appear centred in the E-reader screen. If you leave it left-aligned it will look odd. This also avoids having an indent if the “Normal” style is applied. If the image is the full width of a reader and an indented is part of the applied paragraph style it may push the image off the page if it does not fit. If this happens your file may be rejected by the E-retailer.
Images on separate pages
If you want to have all your images displayed on a page of their own, some of the converters offer this as an option when converting. If not, you can force the issue by applying a heading style that has the “Page break Before” option ticked in the paragraph options.
Text in Images
If avoidable do not use text as part of an image. There is no guarantee that the reader will be able to read it properly on all devices. Put the explanatory text above or below the image so that the text can be re-sized to meet the customer’s needs.
Pricing your Book
In an earlier Post we talked about the impact of file size & download costs and the erosion of your profit margin when you have Witholding Tax, VAT/Sales Tax and distributor charges deducted from your sales revenue before you get YOUR cut. Clearly the whole issue of pricing is key to making your book a commercial success. If you have a book with a lot of images you need to make sure that you keep them small enough to stay within sensible limits. I am repeating a couple of paragraphs here to remind you of the issue.
If you distribute through Amazon you need to keep an eye on the final size of the file. This is not generally a problem with a narrative book but as soon as you start adding complex formatting and illustrations/images the file size will increase rapidly, especially with Kindle files.
There is a limit as to the size of the file you can upload to their site but you need to keep in mind that Amazon charges a delivery fee of $0.15 per MB. This is deducted after all other costs so basically comes from YOUR profit margin.
If you have a 10MB Ebook will cost you $1.50 per sale for your customer’s download.
If you have a complex book with lots of lovely photos and it has a size of, say, 50MB it will cost you $7.50 for every download. You really need to look at your pricing policy when you have a big book or you might end up owing them money for every Ebook you sell.
A final note
Narrative nonfiction with just few images can be a good DIY project. However, if you are planning anything more complex you can save a lot of time and trouble by getting some help. So, unless you’re an accomplished Ebook formatter, with all the software tools available hand to do the job completely, add the cost of some professional help to your overall cost analysis.
Useful Links to FREE Software
If you need a free e-book reader to use on your computer the following programs are good:
Kindle Previewer for .mobi files
Allows you to simulate different Kindle readers to see how the book will appear to a reader.
Important Note: If you use Calibre to view your EPUB file book it inserts an additional file inside the META-INF directory with the title “calibre_bookmarks.txt”. This may cause a problem during EPUB validation so if you are converting to EPUB don’t open the final file with Calibre before you upload.
Guidelines from Major aggregators:
Barnes & Noble Nook Press
Smashwords Style Guide
If you plan to go directly, using Apple iBooks Author, here is the link: http://www.apple.com/support/mac-apps/ibooksauthor/
If you just want guidelines about formatting for Apple try https://itunesconnect.apple.com/docs/iBooksAssetGuide5.1Revision2.pdf
Text Editor for PC
Notepad++ This is a free, open source, program. http://www.notepad-plus-plus.org/
Probably the best Notepad alternative for Windows PCs ‑ and much better if you ever want to edit the HTML in your Ebook.
Text Editors for MAC
Unfortunately Notepad++ is not available for Mac so here are a couple of decent alternatives that are also FREE – and these have versions that work on the PC and other OS’s too.
Tools to Crack open EPUB & MOBI files
eCanCrusher, from Rorohiko.com is designed to convert an EPUB folder into a compressed .epub file or vice versa. It needs no installation. To convert, you just drag/drop an EPUB folder or an .EPUB file onto the eCanCrusher application icon. There are versions for both Windows and MAC: http://www.docdataflow.com/ecancrusher/
Cracking open a Kindle file is more complex than working with an EPUB but if you need to do so you can use KindleUnpack (formerly MobiUnpack) to unpack and inspect the contents of DRM-free Kindle Books or MOBI files. You can then modify the content as needed and rebuild the original with Kindlegen.
The program is Open Source and you can get it here… http://www.mobileread.com/forums/attachment.php?attachmentid=130313&d=1414622013
And you can get more info here… http://wiki.mobileread.com/wiki/KindleUnpack
The Online EPUB Validator is available at: http://validator.idpf.org/ If you want to use the downloadable version from your computer you need to be sure that you have Java installed. If you are an Expert user you can download the core Epubcheck software from: https://github.com/idpf/epubcheck.
If you get an error message that is not readily understandable check on the EPubcheck website https://github.com/IDPF/epubcheck/wiki/Errors and see if they give more details before you start a wider web search.
You can download the Pagina checker from:
That’s it for now!
Once you have had a chance to read through all the posts, and try out some of the things we talked about, we would welcome your questions, comments and suggestions for other Ebook subjects that you would like to read about.
Next week there will be a Q&A running all week where we will ask you to post your questions in the comment sections of the posts so that everyone might benefit from the answers.
©DavidCronin 2015 The Ebook Doctor
Links for the previous 11 parts to the series
After over 30 years as a senior executive across the cable, telecommunications and cable television industries, David Cronin founded the Indie Publishing company Moyhill in 2004. Already involved with computers since the mid 1970s he quickly made the transition to book designer and publisher and the first book that Moyhill published in 2004, The Red Tailed Hawk, in Spanish won best digital print book in the UK that year.
Since then Moyhill has set up authors as their own publishers and has formatted several award winning novels and non-fiction titles. It is essentially a one-man operation and this enables a one-to-one relationship with authors throughout the entire process.
After this series has been completed next week David will be holding a Q&A session via the blog for those authors who have read the series but still have questions.
If after that you feel you need more assistance to give your book a final polished format then you can contact him direct on TheEbookDoctor@gmail.com