JPG

I am always reading about jpg artifact issues, and how the computer compresses the data each time the file is saved.  Being the curious creature that I am, I thought I would see how this works.  I took a standard image in my collection, a flower I shot at a rest stop last summer, and saved it 50 times with a new name.  I closed the file and opened the new one each time.  I saved the first image as daisy. (I don't know if it is a daisy) then closed it and opened it again, saving it as daisy1, and so on till I reached daisy50.  Here is the original and daisy50.

Original image

Image after 50 Saves

Here are closeups of each.

Original

Daisy 50

The differences are so slight to the eye, I am no longer worried about jpg artifact, nor do I see any reason to take up all the data space working in RAW.  But that's just me, you do what you want.