(If this already has a thread or article or page or anything covering this topic, please feel free to direct me to it--I wasn't able to find anything in my searching.)
Hello! (I'm not a regular poster, but I do lurk and read things sometimes
Okay, so I'm working on a physical-book-to-ebook-conversion project. Most things are going well.
One issue is that the physical book has a big landscape chart which is sideways in the book--no big deal, turn the book sideways and read it. However, when you put the chart image into the epub with the same orientation, certain readers will just rotate along with you (iPad, Kindle Fire, basically anything with an accelerometer).
To be clear, imagine that your device is in portrait and you're reading along. You hit a chart that is sideways, the next at 90 degrees to the rest of what you've been reading. You rotate your device 90 degrees to see it properly, and the content then rotates again so that it's still 90 degrees off.
So, here's my inital reaction, since I'm an iPad user and used to rotating the device based on the content: rotate the chart 90 degrees so that it's properly oriented to the rest of the text. Then, if you're reading along in portrait, you can rotate your device into landscape to get a good view of the thing. Then you can go back to portrait. To my knowledge this will work on a Kindle (though I don't own one, I have tried several models out). Even if the landscape chart is "squashed" in portrait, when you click on the chart it goes "fullscreen" and rotates to whatever orientation best matches the dimensions of the picture.
On the other hand, if the chart could somehow be "locked" so that it doesn't rotate at all, that might be preferable. (I think you could have two versions of the image and do some CSS hacks or something. I've seen something like this done on the Fire.) Here's potential problems with the above scenario that would make locking seem like agood idea:
1) When you first view the page (in portrait) the chart will be squashed.
2) The user will have to know to rotate his device/click on the image.
Anyway, in spite of the above 2 points, my gut (and several years using devices that change orientation) tells me that we should just "straighten" the chart and force the user to view it in landscape if he wants a good view. But I can't find anything to back this up--any articles on best design practices, ebook UX, stuff like that. I also don't read ebooks on all available devices, so I may not be factoring in some certain reader's behavior--and we want to make files that are maximally compatible with everything.
So I'd like to see if anyone can weigh in! I know there's a lot of knowledgeable people on this forum, with years of experience in both reading and creating ebooks, so I'd like to hear some opinions. Also, if anyone can point me to any articles or wikis or anything that specifically cover this topic, I'd appreciate it.