"Speed bump" problem: when previewing on the iPad, the first page of each new chapter or section sticks and loads slowly. How can I fix it?

Question

I am building a book with text and photographs in iBooks Author, basing the design on my publisher's layout for the hard copy version.  Whenever I introduce a new section or chapter, I hit a "speed bump" when previewing on the iPad.  As you read, the first page of the new chapter or section is very hard to turn and sticks as it loads.  Within each section the pages flow very easily, but when you reach the next section you hit another speed bump. I have experimented with many possible solutions to no avail.  It does not seem to matter whether the new section has images or just text; the speed bump occurs regardless.

Answer 1

Joel Pickford wrote:
However, I am finding that using fewer sections with more content in them minimizes the problem (i.e. fewer section-transions means fewer speed bumps).  This is contarary to the support page's suggestion of keeping chapters and sections smaller.  I am not having any problem within each section, even with lots of full page photos.
That recommendation was made, presumably, to reduce the length of the delay for each chapter. More content in the chapter means more delay when changing chapters. Of course, if you have lots of little chapters, the delay can still be annoying because, even if only four or five pages in a chapter, the delay is still noticable. Just pick something that works for your book and don't worry too much about the delay. Your readers will be familiar with it if they've seen more than one IBA book.
Will the choice of color space, s-rgb or Adobe rgb 1998, affect file size?
Should I try to compress them more- say, level 5 or level 4 in Save For Web?
Should I size the images for the iPad 2 instead of the iPad 3 retina display, since there are more 2s out there?
Which color space you use does not affect file size. Apple recommend to use sRGB, so I would stick with that. As to compression and sizing, only you can decide. Try and borrow an iPad 2 to make a judgement at what level of compression and resolution you think the images start too look bad. Your high-rez images for the new iPad will be down-sampled for display on the older models, which will introduce additional artifacts.
For my book, I simply used images at 1024 x 768 resolution. When viewed on a new iPad, they look just fine. The lower resolution is basically unnoticeable (at least for my purposes). You can view a sample of my book here: "Djembe Construction: A Comprehensive Guide". If you think the images there are good enough for your purposes, you could down-size your images to half their resolution, which will reduce file size about around a factor of three.
Michi.