Photos won't appear full screen

Weird issue. My photos (regardless if I view them in metro or a desktop folder) won't fill the entire screen. Instead there is a black bar on the left and right of the photo. How do I make images take up the entire screen? I have a Vaio Tap 20 inch all in one with the latest version of windows 8.

Thanks

I have never been able to get my pictures to be full screen or getting a full screen slideshow on my 8.1 laptop. I have Adobe Photoshop Elements 12. Hopefully you will get some positive replies. I have a Sony Vaio touchscreen.