I'm stumped. I thought this would be obvious and easy, but no luck. I'd like to extract the full size jpeg preview from a DNG. Ultimately I'd like to batch/automate this process, but right now I'd be happy to find a solution. I have found that Photo Mechanic from Camera Bits will do it, but surely there must be more. I need a Mac solution, but a Mac and Windows solution would be very helpful. I downloaded ExifTool, which I thought would do it (and maybe does, but the command line stuff is beyond me). Any help would be greatly appreciated, Lee

Hi,

Adobe DNG Converter (and Lightroom, AFAIK) can create DNG file which can contain medium or full size preview (but not both in single file). Before extracting preview, you should know which size DNG contain.

To extract medium preview, use:
exiftool -b -PreviewImage FileName.dng>MediumPreview.jpg

To extract preview image from DNG which has embedded full preview, use:
exiftool -b -JpgFromRaw FileName.dng>FullPreview.jpg

So, for example, using -JpgFromRaw with dng which has embedded Medium size preview, will give you nothing.
I hope that will help you... Greetings,
Bogdan

Sorry, I'm not familiar with Mac usage at all. But, I'm quite sure, using ExifTool, everything is possible.
Anway, if you're serious abour metadata, it really is worth to spend some time with ExifTool docs and tryout some (at least) basic things -to get the feeling "how stuff works" :-)

Greetings,
Bogdan