DNG versus RAW


Today’s Question: What do you lose by using the Adobe DNG Converter to convert RAW to DNG and then import into Lightroom? I am on version 5.7 of Lightroom and recently got a camera that is not supported in that release (primarily used for video but occasionally stills). I am reluctant to upgrade Lightroom, and have been editing the files in Lightroom in the DNG format. What am I missing in terms of the particular camera profiles or anything else by not being on the Adobe supported profile for this camera?

Tim’s Quick Answer: For all practical purposes, most photographers would not be giving up anything at all by converting their original RAW captures to the Adobe DNG format. This is a common approach to working around the lack of support for newer RAW capture formats in older versions of Adobe software applications.

More Detail: There is the potential to lose access to certain “private” metadata that your camera may have included in the RAW capture, and that the Adobe DNG Converter doesn’t know about. However, the actual original capture data and the standard metadata (such as color temperature settings, for example) would be preserved.

The only other disadvantage from a workflow standpoint relates to the fact that with the Adobe DNG format all metadata is added to the DNG file rather than to an XMP “sidecar” file. I prefer to enable the option in Lightroom to write metadata updates to my original captures (found on the Metadata tab of the Catalog Settings dialog). This provides a real-time backup, and also ensures compatibility across different applications that might show the metadata for my images.

My preferred backup solution involves synchronizing my source drive to a backup drive. With RAW captures if I make a change to an image, only the XMP file on my hard drive is actually updated, with the RAW file remaining unaltered. That XMP file is very small compared to the original RAW capture, so my synchronization backup requires very little time. By contrast, the same update for a DNG file would cause the entire DNG file to be updated, resulting in more data needing to be synchronized during backup.

But in terms of the actual contents of your photo, there is really no significant reason to avoid the conversion to Adobe DNG if you prefer not to upgrade to the latest version of Lightroom (or Photoshop). All of the original pixel data will be preserved when the Adobe DNG Converter processes your captures. That said, my personal preference would be to preserve a copy of the original RAW capture files, just in case those ever prove useful in the future.