Is anything lost converting to DNG?

[Tompas]

I have configured my Pentax cameras to use the DNG format instead of Pentax own raw format since I got my first digital camera.

Why?

I think it's a no-brainer. When I have the choice between a proprietary file format and a well documented, open, free to use format -- why should I risk potential trouble in the future?

Compatibility is also better. Every imaging software supports DNG files. Not all of them may support every proprietary format.

Problems so far? None, as expected. YMMV, of course.

 

[Ranchu]

Don't do it! It's a huge mistake! Keep your original files!

🙂

 

[benmacphoto]

Speaking from my own experience.
My main editing program is Adobe CS3, and current raw formats are not supported by it.
I convert newer raw files to DNG to use in CS3.
So I'm not sure where the idea comes from that it's locking users into future paying schemes, when I'm using software from 2007.
I have never noticed a loss in image quality from converting to DNG.
However, I do not delete the raw files in exchange for the DNG files.
Hard drive space is cheap.

 

[Bill Clark]

RAW works for me.

I have to remember to use sun screen!

Seriously, I used to back up my raw files with DNG but quit doing it. For backup I use the raw files only.

 

[willie_901]

...When I have the choice between a proprietary file format and a well documented, open, free to use format -- why should I risk potential trouble in the future?

Except DNG is not proprietary in any way. It is a patented file format.

DNG 1.4.0.0 Specification (October 2012)

"Download the specification, which describes a nonproprietary file format for storing camera raw files that can be used by a wide range of hardware and software vendors."


Grant of rights

"Subject to the terms below and solely to permit the reading and writing of image files that comply with the DNG Specification, Adobe hereby grants all individuals and organizations the worldwide, royalty-free, nontransferable, nonexclusive right under all Essential Claims to make, have made, use, sell, import, and distribute Compliant Implementations.

“Compliant Implementation” means a portion of a software or hardware product that reads or writes computer files compliant with the DNG Specification.

“DNG Specification” means any version of the Adobe DNG Specification made publicly available by Adobe (for example, version 1.0.0.0 dated September 2004)."

Adobe can on revoke usage rights under two specific circumstances: if you sue Adobe for a patent violation related to DNG or if you refuse to acknowledge DNG is used in your software product (application). Otherwise there are no usage limitations.

Revocation

"Adobe may revoke the rights granted above to any individual or organizational licensee in the event that such licensee or its affiliates brings any patent action against Adobe or its affiliates related to the reading or writing of files that comply with the DNG Specification.

Any Compliant Implementation distributed under this license must include the following notice displayed in a prominent manner within its source code and documentation: "This product includes DNG technology under license by Adobe Systems Incorporated.”


Given the facts, I can not see how using DNG represents any threat to long-term data access. Converting DNG to future file formats is technically simple and legal.

If one want's to store post-production rendering parameters with the raw data, one will use more storage space than just storing the raw data alone. The decision: is will the data be stored with the raw data or separately? Each has advantages and disadvantages.

Finally, storing the original raw files independently of DNG conversions is just one way to back up original data. I do this and think of the raws as as sleeves of negatives. I never use them, but I then rarely used negatives after they were printed or scanned.

 

[mdarnton]

I would think that if one were opposed to proprietary formats then the one to avoid would be the camera manufacturer's own. Lots of bad thinking in this thread.

Does anyone have any REAL reason to avoid DNG?

 

[Godfrey]

I would think that if one were opposed to proprietary formats then the one to avoid would be the camera manufacturer's own. Lots of bad thinking in this thread.

Does anyone have any REAL reason to avoid DNG?

Yes, it seems that there are several contributors to this thread who are both misinformed about DNG and have a lot of rancor towards Adobe. The emotional tone of their responses obscures any objective content in their criticism.

The only real reason to avoid DNG format is that you might prefer to use software which does not work with it. Most third party software works with DNG format very nicely, in my experience, even though some only partially implement the full DNG spec and are thus incompatible with some types of DNG files or DNG files made from raws of some cameras.

For example, if you like using the dedicated image processing software from Nikon, Canon, or Olympus, stick with the native raw files. The camera manufacturers' image processing software is generally speaking the only way to obtain results from raw files that matches perfectly the in-camera settings with the advantage of greater control finesse than the camera's controls can offer, if that's what you are after.

There are a couple of advantages to working with DNG files for some purposes, and with some software. For most purposes, however, it's pretty much a toss-up as to whether a native raw or a DNG file provides any advantages.

G

 

[Ranchu]

I would think that if one were opposed to proprietary formats then the one to avoid would be the camera manufacturer's own. Lots of bad thinking in this thread.

Does anyone have any REAL reason to avoid DNG?

I never said I was against a 'proprietary format', that's adobe's framing that YOU have internalized. gavinlg and jarski gave you real reasons, and so have I, you're just trying to pretend it didn't happen. You can't just put your fingers in your ears and wait for an explanation you can tolerate. Well, I guess you can. At the end of the day, there's no reason to use it, and some good reasons not to, and good reason not to trust adobe with your files.

 

[Godfrey]

Don't do it! I thought it would be a great idea to convert all the files from my 5d mk1 in the year 2011 to DNG as an experiment. Looking back 5 years down the track, adobe has made significant strides with their raw conversion of 5d files of which all the CR2 raw files can utilize, but the DNG files can not - meaning they are stuck with the 2011 method of conversion while the CR2 files of around the same time have less noise, better sharpness, and use the much improved parameters of adjustment. ...

It's not clear what you mean.

In Lightroom or the latest versions of the Camera Raw plugin, using Canon .CRW or .CR2 raw files, I can apply Adobe's process version 2003, 2010, or 2012 raw conversion algorithms. I can do the same thing with .DNG files created from those original native raw files.

• What problem are you having applying the newer process versions to your older DNG files?
• Would you supply an original .CR2 file and the .DNG file you created from it so that I can see what the issue is?

G

 

[Ranchu]

Well, maybe he saved the settings in the file instead of a sidecar file, or maybe he wasn't BOUGHT THE NEW ACR? jarski has an issue too, don't forget that one. The thing is, if you don't use DNG, you don't have these problems, and you've lost nothing but the leechlike habits of adobe. Me, I'm pissed all I have is those lousy DNGs and I can't use a decent raw converter with them.

🙂

 

[Godfrey]

my whole raw library since 2007 or so, has been converted to DNG. often it was automatic step when I was pulling files from card to computer. I continue with current project am having, but then stop conversion. Reason is same as mentioned above few times.
...
there are DNG files and DNG files. these in-camera DNG's can be opened editors like Capture One without problems. but if you try to use converted DNG, only Adobe's own software continue to work as intended. Converted files basically lock user into Adobe's realm, and their future paying schemes.

Some software vendors choose to implement only a partial subset of the DNG specification, which restricts compatibility. Aperture and Capture One both did this (although their implementation and the restrictions created were different between them), although I think the latest versions of both these software packages allow wider latitude and cover more of the DNG spec.

I'm more familiar with Apple's implementation ... It does not support the "linear RGB" form of DNG conversion (mostly used by scanner software as an output format, but also by some correction packages that operate on the raw data by doing Bayer interpolation and then applying the corrections on a channel-wise basis). This implementation also did not provide compatibility with DNG files that the underlying image processing library didn't have a native raw color spec for; that was done specifically because they didn't want to produce a color spec that they hadn't tested.

These problems are not the fault of the DNG specification or conversion. There are plenty of image processing packages which accept all DNG files and process them properly because they implement the full DNG specification. These incompatibilities are behaviors of specific app implementations addressing the goals and intent of their app providers. As I said in my response elsewhere in this thread, the only reason NOT to use DNG is because you want to use image processing software with which it is not compatible. These sorts of problems fall into that category.

G

 

[Larry H-L]

It's possible with DNG, to include the manufacturer's entire RAW file inside the DNG wrapper, you just have to check a box and live with a slightly larger file size. You can then extract your original file if you wish at a later time. This gives you choices.

If you use a camera with proprietary files, and that company goes under and no longer supports their file format, you could be stuck with files you can't open years later, unless they can be opened by other means, such as DNG.

Isn't Adobe's DNG RAW converter still FREE as a download?

 

[Godfrey]

Well, maybe he saved the settings in the file instead of a sidecar file, or maybe he wasn't BOUGHT THE NEW ACR? jarski has an issue too, don't forget that one. Me, I'm pissed all I have is those lousy DNGs and I can't use a decent raw converter with them.

🙂

With DNG files, settings are always saved into the DNG file instead of into sidecar .XMP or XML files. That is one of their advantages over native raw files. No software designed to work with DNG files should have any problem reading settings stored in the DNG files. The Adobe raw process version is not a part of the DNG specification and makes no difference to the DNG files' compatibility.

If one chooses not to buy the current raw converter, I don't understand the point of complaining that you can't use its features. However, it seems he has purchased the new raw converter since he seems to be able to use it with his .CR2 files.

There are plenty of "decent raw converters" that can process all .DNG format files. While not 100% current, this page lists a healthy number of them:
http://www.barrypearson.co.uk/articles/dng/products.htm

G

 

[Godfrey]

It's possible with DNG, to include the manufacter's entire RAW file inside the DNG wrapper, you just have to check a box and live with a slightly larger file size. You can then extract your original file if you wish at a later time. This gives you choices.

If you use a camera with proprietry files, and that company goes under and no longer supports their file format, you could be stuck with files you can't open years later, unless they can be opened by other means, such as DNG.

Isn't Adobe's DNG RAW converter still FREE as a download?

Yes, it is. http://www.adobe.com/downloads/updates.html provides links to update DNG Converter for both OS X and Windows platforms.

G

 

[Tompas]

Except DNG is not proprietary in any way. (...)

Yes, but that's what I said.

Is my English really THAT bad that you had to get me THAT wrong?

My point of view again, in hopefully clear enough words, for the record:

DNG: good. No problems. Can be read in a thousand years.
Proprietary vendor file format: potential trouble if vendor stops support.

 

[Doug]

DNG is a solution to the proliferating mess of mutually-incompatible proprietary raw file formats, a benefit to the community as a free and universal format. Good for Leica in adopting it instead of yet another proprietary one, and good for those other manufacturers (like Pentax) whose cameras offer a DNG output option.

 

[gavinlg]

It's not clear what you mean.

In Lightroom or the latest versions of the Camera Raw plugin, using Canon .CRW or .CR2 raw files, I can apply Adobe's process version 2003, 2010, or 2012 raw conversion algorithms. I can do the same thing with .DNG files created from those original native raw files.

• What problem are you having applying the newer process versions to your older DNG files?
• Would you supply an original .CR2 file and the .DNG file you created from it so that I can see what the issue is?

G

That is exactly the case - I cannot seem to process any of the DNGs I converted using the current version of lightroom with any of the newer processes. The option for it is greyed out. Meanwhile I've never had any issue of the sort with ANY of the proprietary manufacturer raw file. I seem to remember the issue being the conversion process, I converted to DNG when I should have converted to DNG instead. Why have different kinds of files with different functions under the same extension? Why not have warning that you can't update conversion processes with one of the DNG files but not the other? What an absolute mess.

I see the whole issue as a big non-issue. Every single raw file from the beginning of RAW processing is still compatible with most if not all conversion software. Do you think something obscure like DNG format is more likely to be supported into the future than the trillions of NEFs and CR2's floating out there in the world? Probably not, seeing as companies support and code for numbers. And even if the manufacturer raw file isn't supported past a certain point, you could THEN convert it into a DNG file as a last resort - the converter isn't going anywhere.

 

[Godfrey]

You didn't say how you converted your files to DNG. Did you use Lightroom or DNG Converter? What settings did you use in the DNG conversion?

You say, "... I cannot seem to process any of the DNGs I converted using the current version of lightroom with any of the newer processes. The option for it is greyed out. ..."

There's a display bug in Lightroom 6.1: When you go to the Develop module and open the Camera Calibration panel, sometimes the Process Version popup is grayed out.

Just click on it and you'll get the popup menu:

After which you can see that it is set properly:

After you do that and make an adjustment, the setting will stay visible. I submitted this in a bug report to Adobe when LR6.1 was released. (Note: the example images above were made with an old .CRW file from a Canon 10D. I don't have any 5D .CR2 files, that's why I asked you to make one available.)

Have you tried that?

G

 

[Godfrey]

..
I see the whole issue as a big non-issue. Every single raw file from the beginning of RAW processing is still compatible with most if not all conversion software. Do you think something obscure like DNG format is more likely to be supported into the future than the trillions of NEFs and CR2's floating out there in the world? Probably not, seeing as companies support and code for numbers. And even if the manufacturer raw file isn't supported past a certain point, you could THEN convert it into a DNG file as a last resort - the converter isn't going anywhere.

The problem with that logic is that the testing of raw converters has to happen on a camera by camera basis, not on a NEF, CR2, CRW, etc basis. This means that the software testing for a raw converter process become more and more difficult to do properly and completely as time goes on because of the additional testing needed for every new model camera. Generally speaking, the older models are often long gone at this point in time, but there will come a point where their raw files might not convert because it is no longer cost effective to run the testing on all those old files.

It's the undocumented NEF, CR2, CRW, etc file formats that will have problems when that happens. DNG format is well-defined and publicly accessible. Yes, there are several variations ... Properly written software knows how to handle all of them.

I agree it isn't a problem ... yet. Which is why I said the only compelling disadvantage to using DNG files (where they are not out of camera native format) is that they might not be compatible with specific software you might want to use, and that while there might be specific advantages to DNG in some circumstances and to native raws in others, at the present time it's otherwise a toss-up.

G

 

[f2bthere]

If you are using Adobe products right now, there is no problem right now. But the purpose of this question is really about your future, and that requires speculation.

I have been using photoshop and Lightroom for my image processing. I just tried Capture One on a few files to compare how it deals with the files compared to Lightroom. Even though I haven't really learned Capture One yet, it already seems that Capture One does a better job with Fuji files.

There is a reasonable chance that you may have that experience in your future. If so, it is better to have your camera's original RAW files.

You can, indeed, store them inside the DNG file, but then you might have to extract them. Saving both formats or the DNG with the proprietary RAW format in it take up about the same amount of disk space.

The hope was that DNG would be universal. The reality is that this has not come to be, at least not yet.

Disadvantages of DNG
-loose access to any manufacturer's proprietary information stored in the RAW file
-can't use manufacturer's converter (which might at some time take advantage of such proprietary information).
-can't use third party software that doesn't support DNG now or in the future.

Advantage of DNG
-will presumably continue to be supported by Adobe
-contains a checksum for file validation (you could do this with a third party program without DNG)
-DNG can contain metadata, both tags and LR develop information

I suggest at least backing up your RAW files so you have the option in the future, even if you do use DNG today.