Since starting to use Lightroom a number of years ago, I have just imported my Nikon/Canon/Olympus/Panasonic raw files into Lightroom as DNG and then deleted the raw files. The first time I thought about whether I should do that was when I first took HDR's. I kept the raw files in case I ever wanted to re-process them since I was importing the raw files directly into Photomatix. But my current understanding is that DNG is a lossless format. And since it's likely to be a viable format as long as any of the proprietary formats, it seems to me there may not be any compelling reason to save any raw files in addition to the DNG files. I haven't been able to find a lot of information about this. Am I thinking correctly that the DNG files are essentially the same as the RAW files in terms of the data they contain and the ability to process them? I don't want to sacrifice any future processing ability (as software improves which I'm sure it will) by keeping DNG instead of the original raw files. I also don't want to needlessly keep both. What do you do and what's your thinking behind it?