[pschlute]

Perhaps neither of you know this, but were I to do my adjustments to a jpeg image, every time I saved it it would get littler and littler and lose progressively more data from the original jpeg version. That is the data loss I am avoiding by exporting the original jpeg to a large uncompressed file format. OF COURSE, I don't gain back any data lost in the in-camera jpeg creation. But the OP's question had to do with a camera that doesn't shoot a RAW image like I can, one that only shoots jpegs.

I get the point you make that JPEG is lossy whereas TIFF is not. But you would have to to do many adjustments and many saves for that loss to become apparent. If you were doing that kind of work on a file you would be better off starting out working on a 16 bit TIFF created directly from the raw file.