Apple's support of DNG format is fallacious

Are there any other apps that will read the adjustments? Apart from ACR.

Ian

The adjustments made to images in Adobe Camera Raw are stored in one of two possible locations (The following information comes from Adobe Photoshop CS2 help files):

The Camera Raw Database:
Camera Raw Database Stores the settings in a Camera Raw database file, generally located in the user’s Application Data folder as Document and Settings/user name/Application Data/Adobe/CameraRaw (Windows) or the user’s Preferences folder as Users/user name/Library/Preferences (Mac OS). This database is indexed by file content, so settings remain with the image even if you move or rename the image file.

or

Sidecar ".xmp" Files
Sidecar “.xmp” Files Stores the settings in an XMP file in the same folder as the raw file with the same base name and an .xmp extension. This option is useful for long-term archiving of raw files with their associated settings, and for the exchange of raw files with associated settings in multiuser workflows. These same sidecar XMP files can store IPTC (International Press Telecommunications Council) data or other metadata associated with a camera raw image file. If you open files from a read-only volume such as a CD or DVD, be sure to copy the files to your hard drive before opening them. The Camera Raw plug‑in cannot write an XMP file to a read-only volume and writes the settings to the Camera Raw database file instead. You can view XMP files in Bridge by choosing View > Show Hidden Files.

As you can see, neither of these options embeds the adjustments into the file itself. Therefore it is not possible for Aperture to read these adjustments.

DNG can embed the information that is normally kept in the database/sidecar/XMP files. One big advantage of using DNG is that one doesn't have to deal with XMP files or a database.

However DNG embeds no information on how to interpret the correction parameters which are stored in it.
I don't believe the DNG spec addresses how an image should appear. That is up to the RAW converter.

Jeff

The adjustments made to images in Adobe Camera Raw
are stored in one of two possible locations (The
following information comes from Adobe Photoshop CS2
help files):..............

As you can see, neither of these options embeds the
adjustments into the file itself. Therefore it is
not possible for Aperture to read these
adjustments.

This is incorrect. DNG does support embedding of adjustments informaion. This is the advantage of DNG. The Camera RAW Database and XMP sidecar files are necessary for other RAW file formats that do not allow the embedding of information.

Quad G5 Mac OS X (10.4.3) RAID, 30" Monitor....

Hi Donland,

Try this. (I just did)

Edit a RAW file in ACR (in my case a .CR2 file), and use the save option to save it as a .DNG, in a different directory (so you know the .XMP file will not be associated).
Then open the .DNG file in ACR. The adjustments you made are still there, and if you look in the directory where you put the .DNG (with Finder), there is no XMP.
My ACR preference is set to use sidecar files, so I know it is not in the ACR database.
But just to be sure copy JUST the DNG file to a pc system and open the file in ACR, and the original adjustments are still there.

A major advantage of DNG files is that they are designed so that the equivalent of a sidecar file is embedded in the file itself. So not only does the DNG file carry the adjustments, it also carries any other metadata an application associates with the file.

In Aperture's case the metadata embedded in the DNG file is ignored, and the metadata is stored in the database, as it is for any other image file.

If you really want to go crazy, modify the metadata of the DNG file in Bridge (change creator: job title to "Master of the Universe" say), and open the DNG file in PhotoMechanic, and the changes you made will be there.

Jeff

dual g5 2ghz Mac OS X (10.4.3)

Hi Ian,
I haven't found any.
I can however open a .CR2 in DxO Optics, remove distortion and chromatic aberation and vignetting, and save as a DNG. ACR will then read the DNG with the lens corrections made by DxO.
PhotoMechanic can't read the DNG file, and neither can Aperture.
I don't think this is what you were asking for, since DxO appears to modify the RAW data itself (destructive editing for sure, but good destructive)
Jeff

dual g5 2ghz Mac OS X (10.4.3)

I absolutely agree, never did argue the point that Aperture did not pick up the DNG info. Just said that Bridge embeds info into the DNG. I also agree that this is a very large sticking point I have with Aperture. I just hope they offer the option of embedding informaition into the exported files as well as the ability to change the name of the file after importing. I understand their desire not to touch the files, but given that I would bet 99.9% of photographers would want to edit down first and then change the names on the keepers I think the developers need to change their paradigm on not touching the original files, after all, that was the idea behind DNG.

Imagine 2 workflows.

The current Aperture:
Open Aperture
Import 500 files
Cull out 200 files.
Keep 300 files
Don't bother correcting because of the need to export and all the metadata will be lost.
Export the keepers.
Delete the remaining 300 files in Aperture
Open Bridge
Open the just exported files.
Wait for them to load.
Rename the files to what you want because Aperture forces a space in the name and you do not want that space.
Enter all the file shoot info so if you export from Aperture, the metadata info that was imported within Aperture stays with the file and only that info.
Close Bridge
Reimport 300 renamed files back into Aperture
Done, I think.....

A new Aperture (Hopefully)

Open Aperture
Import 500 Files color correcting on the fly to see if they are keepers.
Cull 200 Files
Rename the remaining 300 files.
Enter all file shoot info.
Done

The new Aperture now writes all the info back to the original file including filename, metadata etc. Everytime you export or open in Photoshop, Aperture passes the filename and metadata info along. Life is good.

Granted they currently do not want to write into the file, but most of us would prefer it so when we send something to a client we do not have to keep reentering it. Furthermore, all of us would be doing it anyway, just in a different app., so whats the difference? I am very very hopeful they will correct this quickly in a future version, if not, it is a deal breaker for me, not to mention the other deal breakers it currently has.

Hi again donland1,

Whoops; I must have been feeling argumentative this morning. I think I read does as does not. I see we are in agreement. It is a huge pain that Aperture ignores embedded metadata in RAW files, especially DNG files.

Jeff

dual g5 2ghz Mac OS X (10.4.3)

I suspect Aperture ignores the sidecar information in the DNG files because Aperture's filters are too unlike any other program's filters to produce accurate results.
For Example, note that Adobe (along with 99% of other PP programs) use Curves. Aperture does not. Therefore creating translators for all of the filters from other programs would be difficult and probably against intellectual property laws.
I think the idea makes sense. P.S. I am in no way defending Aperture.

Dustin.

As others have correctly stated, the corrections should be stored within the .DNG. One of the significant advantages of the format is ability to do this and not associate with sidecar files. That said, there are different versions of .DNG. The current version is 1.1.0.0 specs, which CR/DNG 3.2 now writes. Is Apple’s OS using that current spec?

This is incorrect. DNG does support embedding of adjustments informaion. This is the advantage of DNG.

This is incorrect. DNG supports embedding of any information you want, but the Adobe Camera Raw adjustment information is as specific to Adobe Camera Raw as Aperture's adjustments would be to Aperture.

The information that is saved with the DNG is the collection of settings you have applied in ACR. They are, necessarily, only meaningful to ACR. It is not possible for Aperture to duplicate them.

What do they mean by support of Adobe's DNG format then?

They mean it can load the files.

Of course, their "support" of DNG is pretty incomplete, even there -- it can only read DNG files if the camera's native RAW files are supported, which is silly. A proper DNG reader would have no such restriction.

But expecting the ACR adjustments to be duplicated by Aperture is just a fundamental misunderstanding of what DNG is. The only way it could work is if Aperture used ACR to perform the conversion. Otherwise it's just a list of numbers that don't correspond to any settings within Aperture.

The DNG support should include linear storage of any image so that there is at least a 'Universal' level of support if necessary. If adjustments are made to a raw image then saving in DNG as a demoasic'd image would allow the image adjustments to be rendered.

Even better, it should just support the full DNG spec. The new Hasselblad and Leica cameras(which output only DNG style raw) are supported by ACR 2.4, which was coded before those cameras were created. I assume DNG parameterizes the Bayer pattern used by a camera, such that a new sensor can be characterized within the DNG spec. It would appear that the linear option is a fallback compatibility mode.