Aura One rotating pages on its own when reading .cbz files

[Crane]

So I have a whole bunch of manga. Some pages are single pages, some are two-page spreads. I've rotated the two-page spreads so that they're in a portrait format, so that when I view them on my Kobo I can just turn the reader sideways, rather than having to rotate them there and then flip through three more rotations to get back to the right orientation for the next single page.

However, when viewed on the Aura One, some of these pages are rotated back to a landscape orientation and squished to fit the width of the display!

This doesn't happen with all of them however. Does anyone know what's up with this?

[Ripplinger]

It's possible that Kobo readers are touchy about the exif data for images. I don't read cbr or cbz on my readers, but it's a definite issue viewing images that are rotated say on your TV afterwards, etc. It's possible you simply need to get a program that will allow you to change the orientation in the exif info after you've rotated it, then zip it back up and see if that works.

An easy to use older one that still runs even on Windows 10 that I use is PhotoME.

Edit: Another one that's easy to use is Exif Pilot Editor.

[Crane]

Nice idea, but I just checked one of the affected images in Exif Pilot, and it's got an Orientation tag of "Rotate 90 CW" already, so I don't think that's it.
Besides, I rotated all of them the same way, just using the "Rotate" function in Windows, so that wouldn't explain why some work and some do not.

Could it be to do with resolution? Does it perhaps override rotation if the resolution on one axis is too close to the display resolution?

Edit: I'll be damned, it IS something to do with resolution. I ran the whole lot through a batch resize so they all fit within the display size, and now they display correctly. It seems like if the Kobo has to downscale the images to fit them on the screen it also fucks with the rotation. For some reason.