I responded to your other post at
http://chdk.setepontos.com/index.php?topic=1390.msg119593#msg119593There are two separate issues:
1) The file format. This is controlled by the "DNG Format" checkbox in the DNG section of the raw menu. If it's checked, files will be saved in DNG format.
2) The file extension. You can save in DNG format but have a different extension like CRW. This may confuse some programs, but makes it easier to download the files over USB. If you check the "'DNG' file extension" in the DNG section, then the files will have a DNG extension. Otherwise, they will be saved with whatever extension is set in "RAW File Extension"
