Pros and Cons of DNG Photography Files
In this post I will talk about the benefits and concerns about of Adobe’s open source digital negative format. This post is intended to highlight what DNG (Digital NeGative) format is and why it works for me.
The DNG format was introduced in 2004 and is open source. I’ve been converting my RAW files to DNGs since 2010.
The Number One Rule: Do what works best for YOUR workflow: research, experiment and evaluate.
Benefits of DNGs:
- Considered a universal RAW file
- Metadata is written to the file without a separate sidecar file
- Includes checksum information in the file to detect and prevent file corruption
- About 20% smaller than a typical RAW file
- As long as Adobe exists, DNG will exist
Because it’s a universal file, you can combine any RAW format to DNG. For me this is a big plus because if I ever use a different brand of camera or switch brands, I can still maintain one RAW format. This makes a lot of sense for organization and consistency.
Furthermore, for the sake of organization and consistency, removing the side car files and including metadata and RAW images in single files is simpler.
For archival reasons, it’s good to be to have assurances against file corruption. Native RAW formats do not offer this, whereas DNGs do.
Another big plus is DNGs are about 20% smaller. Hard drive space is pretty cheap but the more you can save the better.
Concerns about DNGs:
- Not as compatible with non-Adobe image-processing software
- Additional time to convert
- Possible increase of corruption
- Strips out some of the unrecognized metadata (such as Active D-Lighting and Picture Control)
One reason to to not convert is if you use or think you will use non-Adobe products such as Canon’s Digital Photo Professional. This is proprietary software that won’t recognize DNGs.
It takes time to convert and if you are editing thousands of files at a time, this could represent a significant addition to your workload. I’m not dealing with that kind of volume, so converting as I go for each project doesn’t affect my workload significantly.
You can change the metadata in the DNG itself, which creates an increased chance of corruption. To avoid this you would have to back up your file before making changes.
I have read that the conversion process does remove some of the metadata listed above, but it’s not something I’ve been concerned with.
Why I use DNGs:
I don’t utilize proprietary software and I don’t mind the extra conversion time to get the benefits of a smaller universal RAW file that is compatible with Photoshop, Bridge and Lightroom (the standards I use for processing). You do have the option to embed the original RAW file in the DNG if you want to experiment with the format, but I wouldn’t recommend doing it as a permanent practice because it defeats the purpose of converting. I don’t see Adobe going anywhere soon, so I feel confident in having all my RAW files as DNGs.
There are a few ways to convert to DNG. One way is to download the free DNG Converter from Adobe:
Feel free to ask questions or comment!