It's a pain!
Another downside of Win8.
From what I understand, you can't change it in Win8, as it reads the tag from the original image file, which determines the aspect.
You need to load the images into image software, manipulate it to how you want it, then save.
There's a lot of image/photo software available.
One is Photo Gallery, which is part of Windows Essentials.
Photoshop, etc.
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