Strange Explorer behaviour with thumbnails

[Glenis]

I got a bunch of photos (JPGs)in a folder from my daughter.
If I use Windows XP Explorer to view them (using Thumbnail or Filmstrip
view) many of them are rotated 90 degrees CW. This is not unusual -
she's taken Portrait shots.
However, the strange thing is that when I open them in a Graphics
package (such as Photoshop or Paint Shop Pro or Picassa) they are
magically rotated to the correct orientation!!!
What on earth...?

 

[Glenis]

I got a bunch of photos (JPGs)in a folder from my daughter.
If I use Windows XP Explorer to view them (using Thumbnail or Filmstrip
view) many of them are rotated 90 degrees CW. This is not unusual -
she's taken Portrait shots.
However, the strange thing is that when I open them in a Graphics
package (such as Photoshop or Paint Shop Pro or Picassa) they are
magically rotated to the correct orientation!!!
What on earth...?

Aha! It's the EXIF data added by the camera that's rotating them