Thank you for your answer. Unfortunately, in addition of being slow (transfer one by one for each picture), it does not work perfectly... Or I can save the modified picture but very compressed, or if I try to view in full resolution, edits are lost....
It seems to be a problem of the native photo app of the iPad, because I succeeded to export modified versions of my pictures using upload of Picasa, but they were very reducesized also....
Next time I will use other application for modifying my pictures, and no longer the native of the iPad....
Did you have other comments on this from other people ?