Epub Multiple Images

It's all about the reflowable part. There are no pages in that format; there is only the screen by screen height, or virtual page. While that's usually about 1.5:1 or so in most readers, and variable in desktop readers, there's no assurance and no guarantee how any one reader will choose to display any given series of elements.

Yes, you can force a page break; yes, you can anchor 1-n elements to that break point; yup, within reason, most readers will display the same group of elements on a common page size. But just as many factors will mean the second or third item is broken to a page of its own, and unless each of your page groups is very short — more or less square or a bit less than square, relative to height — the reader's rules will break content (or, if you've tried hard enough, just plain break the content) when it thinks there's not enough room.

The very basic process, of page break + anchored item + second anchored item, should work some most of the time as long as you keep the total height under about 1.25:1 or so... but if any of that is text, and the user sets the font or spacing high... break.

You can make the content one element, by making it all one image, but that means an over-tall image will either be scaled smaller and thus might have readability or resolution problems, or... might even break the image itself across pages, depending on how the reader is configured. As with most other issues in EPUB, you don't have any way to control what reader a user might use, so you can only optimize for one of the basic ones and leave any variations to user choices.

It's best to 'respect the medium' and make the content appealing, useful and readable even if it comes one "element" at a time.