If your original is a jpeg and you open with PS and you do a 'save as' (so the edited version is saved as a seperate file) and close the orginal (with no saving), does that degrade the original file?
Essentially the original file would have been opened & closed in PS unless just opening and viewing a jpeg file degrades it?
If you do not change the file name or do not "save as" to a different folder, the modified file replaces the original file, even when using "save as". What I mean is clicking "save as" and then clicking "save" is the same as just clicking "save" from the file drop down.