Most jpeg images contain some called an EXIF header. This is information about the camera used to take the picture and exposure settings at the time. This EXIF information is used by our Fuji Frontiers to enhance images and to compensate for any underexposure on the camera. Generally, you will get brighter punchier prints if the EXIF information is still there.
Some older photo editing packages can strip out this EXIF information, meaning that our Frontiers can't enhance the image.
Also the act of editing an image at all in PhotoShop, even newer versions, causes the Frontier enhancement to be turned off. Fuji assume that the image has been edited to be how you want it printed and so won't change it any further.
If you are in doubt please upload your unedited images to get the best possible printed results.