Here's a question for all you highly technical digital photogs. My understanding is that, if you shoot in RAW, you end up with a file that cannot in and of itself be changed. What I mean is that you can edit the file, but you cannot save your changes without creating a new file (so if you shoot in RAW, it is impossible to edit the image, save your edits, and end up with only one file). Is my understanding correct? For bonus points, can you direct me to any technical documents (or I guess any reliable and cite-able documents) that state my understanding? You can get even more bonus points if your document explains why RAW files work this way and/or explicitly state that the underlying RAW file cannot be altered. Any guidance in any of these directions would be awesome. Thanks!