Quote Originally Posted by Ron Kruger
Why are you saving images in DNG, instead of TIFF or even JPEG?
This is an accronym I've only seen a few times. What is DNG best suited for?
The reason not to save in Jpeg is obvious. It's only an 8 bit file format, and it has lossy compression. Tiff can save in 16 bit, but it throws away all the data the camera records, such as white balance and exposure. (Just did a little research, and apparently, TIFF is capable of storing metadata, but isn't often set up to do so).

DNG was created by Adobe as a universal RAW format. (It is apparently TIFF format with standardized places for storing camera metadata). The problem with RAW is that it's not a universal format. Every manufacturer saves RAW data in it's on unique file format that can vary even model to model. In theory when you convert to DNG it saves all the camera's RAW data without being make/model specific. This allows software makers to concentrate on tweaking their software rather than writing new RAW compatibility modules every time a camera is introduced. So you only need one converter for each new RAW format. You convert RAW to DNG then any software that supports DNG can use it.

I posed the original question when I noticed that the DNG files were smaller (by just a bit- the original files were always 15 megs, the new ones between 11-14 megs) than the original CRW (RAW) files. It appears that Adobe has used a lossless compression. (It would have been idiotic to use a lossy compression like Jpeg). I was just trying to confirm this. I just did a little more poking around the web and think I've confirmed this. Here's a good source-

http://www.barrypearson.co.uk/articles/dng/benefits.htm

which led me here-

http://www.digitalpreservation.gov/f...ferences.shtml