The Digital Negative file format, or DNG, from Adobe Systems is a universal RAW format file created to address issues facing digital photographers.
The Standard Solution Need
Camera Manufacturers using proprietary formats present challenges for photographers. Each RAW file type works with contemporary software, until the Manufacturer introduces new technology. Legacy issues of how to work with older files is then relevant.
Legacy is addressed in the DNG design by ADOBE by providing one file type for future use. It contains version numbering, provisions for a manufacturer to embed special or proprietary information to let them retain a post processing ‘advantage’, and growth room. Having an open standard RAW file type means the advantage of revisiting older files with new RAW converters and other software will not disappear decades in the future.
Archival requirements of having less file types to recover or to search for in the future is important. There exist already RAW formats that newer data recovery software can only partially recover. Part of the ‘once in a lifetime photograph‘ is not acceptable.
Use of the DNG format as an added archival storage type along with original Camera RAW formats expands the future for each digital photograph.
The Digital Negative
Adobe defines RAW files as camera-produced files that “contains the actual pixel data, or linear data, captured by a camera sensor before it has undergone any processing”. What is stored in a Digital Negative includes the ‘undeveloped’ or ‘unprocessed’ sensor data, EXIF and other camera generated information, and meta-data needed to define how to render the image.
The lossless DNG storage method uses a schema based on TIFF-EP so it already conforms to an available standard. Thumbnails can be included in the DNG file for quick viewing. Technical details for the DNG format is available in a PDF at the DNG Negative Specification link. There is an extensive set of resources including a FAQ page available from Adobe’s web site.
Conclusion
The DNG specification appears to be an important element in Adobe’s current and future plans. The release of a Software Development Kit – SDK, free tools including DNG conversion, a Profile Editor, and increasing use in Adobe products are evidence that DNG will play a central role in the future of Digital Imagery. The Adobe DNG file format is with the tools and resources available currently – ‘The Other RAW File‘ choice for Digital Photographers.
by CD Price
Customization Tool from Adobe for Camera RAW Profiles
Adobe is currently offering a free DNG profile editor to enhance usage options in their Photoshop products (Photoshop, ACR, Bridge, Lightroom, PS/E). Screenshot below of the Color Table adjustment from the DNG Profile Editor. Use of this tools is recommend only for very advanced users. Windows and Mac OS versions are available through links on the Digital Negative Home Page below.
Related DNG Resources:
Digital Negative Home Page at www.adobe.com
Digital Negative Specification (PDF)
Digital Negative White Paper: An Introduction (PDF)
Frequently Asked Questions (FAQ) about DNG from ADOBE
Leave it to Adobe to try and proclaim the standard. One which, to be honest is about 10 years late in coming.
It’s similar to Microsoft trying to adopt web technology and then give it their own name and making it just slightly incompatible with everything else.
A One World file format would simplify things (esp for Adobe). However camera makers are like cell phone makers; if it’s easier for you to switch brands you might bale on them and go buy the other guys stuff. While it’s a nice thought, it’s about as likely to happen as both Canon and Nikon agreeing on a One World lens mount.
Ain’t gonna happen.
Al,
Thanks for taking the time to respond.
The DNG format has been around longer than it appears at first glance. It is approaching ten years in existence publicly, and ten or more internally when one looks at the design work that exists behind this file type.
Once, with film, there was a standard for archiving and reproduction built in to the product. The Camera makers weren’t part of that business and so may have a ways to go catch up to the curve in the digital realm. Few of them have really indicated that they are highly interested in providing all encompassing software solutions.
As far as support, Leica and Hasselblad, to name just two, are supporting DNG in their cameras and using it as an output option. Nikon is even supporting direct output from some of their high end DSLR’s in the TIFF format. TIFF is also a ADOBE file type.
Whether DNG survives or is rolled into a later standard, it does currently provide a base platform that eases the workflow for many photographers. Some who use multiple brands of cameras whether DSLR’s, Scanning, or MF backs, find that having a baseline common file type can be very efficient at certain stages in their workflow.
The archival elements of this cannot be simply dismissed, especially for those with a decade of images already accumulated. I don’t plan on abandoning Adobe post processing software anytime soon, so I feel comfortable in using DNG, at least as a second backup.
I don’t think that camera makers are good application software developers.
Which is why there’s a market for tools like Lightroom and ACR.
But I don’t see a need for yet another raw file format in DNG, where the manufacturers already have their own.
It doesn’t ease my workflow, it would just add another step.
But if I had a Leica or Hassy maybe I’d feel differently.
I’d abandon Adobe software (I’ve already abandoned Canon) in a heartbeat if something better comes along.
So for me support isn’t an issue, DNG format is really a red herring.
Because the camera manufacturers are probably going to be there a long time (recession permitting) I think the third party applications are gong to have to continue to support the disparate file formats that the cameras use.
So the longevity of Abobe in the post processing market is a non-issue for me. Every software developer has to support the multiple file formats.
It may be that eventually software developers are going to get fed up of manufacturers (like Canon) releasing a new, incompatible, raw format with every model release (it seems like it anyhow) and so having to play catch-up.
It could be that a standard eventually evolves that the manufacturers agree on, but I think that’ll be about the time that Nikon, Canon, Sony, Pentax and Olympus all agree on a common lens mount.
In the meantime I’ll continue not to convert my images, work in .CR2 raw format with Lightroom, and not worry about other file formats except for print output and agency uploads.
Thanks for the article, Carleton. I’ve been wanting to understand the DNG format and philosophy for a while. More importantly, I need to understand how DNG can be usefully incorporated into my workflow. And how I will benefit from it. This article suggests to the overall long-term benefits, but doesn’t really address how to use the DNG format right now. I think I just need to start working with it to find out.
As for whether Adobe or someone else should develop a universal format, I think that would be great for photographers. A few years ago I attended an open discussion on this subject at PMA. Some well-known photographers in the audience were very vocal about their desire for a universal format. It used to be that camera makers made cameras and the film companies determined the quality and look of the medium. Now camera makers do it all. And I think that sometimes they fall short on the software end of the equation. How many experienced photographers are willing to use the software supplied by the camera makers? Almost none. Adobe created the digital imaging software standards and I trust them to do a good job with a “digital negative” standard. It would be awesome if when I got a new camera, I wouldn’t be forced to use sub-par manufacturer-supplied software to process my RAW images.
Paul-
Didn’t you see the announcement about the new, universal lens standard?
Joking –
John,
You are welcome. I could have made this a small book easily. DNG for me is like other emerging and newer software in having the need to work with it in a real setting. I had that experience with Lightroom initially.
I attended a few discussions at various events regarding OPEN source imaging files. It was a real hot topic in the commercial printing equipment arena for a long time. Everybody thought they could use one format or another, and forgot that most of the files, were actually proprietary or licensed already. TIFF is the classic example as it too is owned by ADOBE. The ‘format wars’ over everything from GIF, to PNG, to even some JPEG implementations cost a lot of money. Adobe has at least stepped forward and said, here is an open standard, we support it, you can use it, and for now, the tools are included in our products or are free. I think it is equally balanced between being a backup archiving format and and application enhancement at this time. There are emerging uses.
DNG files do let a photographer transport/swap/exchange an image between DNG aware applications far more easily. Cross hardware between PC’s and Mac is a plus. Apple has a growing number of DNG aware applications that are not all Adobe products. As Adobe products are on both platforms, it is another tool.
I have made of DNG files when working with other photographers (such as on a big wedding or in an industrial setting) where two or more people need to make changes. This includes adding metadata or preparing different uses of the same file, such as for Web output or printing to different media.
DNG are exportable as a file with changes embedded in the file. The user does not have to worry about ‘sidecar’ files, the current ‘version’ or an external database of changes for non-destructive work. In addition, if you need the original back, it is still there and hitting RESET in the application restores it to its RAW starting point. Very handy when needed.
DNG has one other feature not widely recognized in terms of archiving; it can embed a complete copy of the original RAW file in its file structure. That does make for huge files sometimes!
If there is a notable drawback to DNG, it is that the DNG file without the embedded original, may loose some of the proprietary information included in the original. The most widely documented is Canon’s Dust Spot mapping for Sensors.
An interesting note is the Profile Editing facility that Adobe is starting to promote. It is similar to Picture Styles from Canon (or vice versa?) and can be applied to any camera format for post processing options. The latest ACR and LR have included all of Canon’s standard styles, and features for other systems. Canon’s documentation of Picture Styles makes extensive reference to Adobe technology as if there has been more cooperation than frequently noted. Adobe has already committed to at least a v1.0 Profile Editor to be provided free.
CORRECTION to my previous post – I cut and pasted most of this and somehow. the following was copied from the wrong version.
I have made of DNG files when working with other photographers (such as on a big wedding or in an industrial setting) where two or more people need to make changes. This includes adding metadata or preparing different uses of the same file, such as for Web output or printing to different media.
It should start:
” I have made USE of ” Caps for emphasis.
- C
I’ve used DNG for years, since Lightroom came along. As LR converts my NEFs during import, it’s not another step for me.
Why I use DNG?
- As Adobe is backing it, I trust it to be more future-proof archival format than a very specific NEF subset.
- Lightroom can write metadata into it, no need for a XMP sidecar file.
- Better compression than my original NEF.