I don't know because I don't post often to this website, but in my work on HistoricBridges.org sometimes when I am working with my photos I find that photos are not rotated properly. I discovered this is because some cameras embed code to tell programs to rotate a photo (different from actually rotating a photo in an editor). Its called an EXIF code, and it defines a rotation. It is a HUGE pain in the butt because some programs recognize it and others don't. For example, the built-in windows viewer does not but Google Picasa does. Worse, sometimes the camera records it wrong. I downloaded a program that automatically wipes the EXIF rotation, which has been working for me.
Lame when somebody posts a bunch of pics here and can't even bother to orientate them properly!
I just viewed this bridge yesterday (2/12/2016). This bridge is now closed.