It’s been quite a long time since my last post. I was busy with work and other stuff, but what is more important, i was on to port my photographic post-processing workflow to linux.
Workflow seems to be a popular word among photographers nowadays, and there are as many workflows as there are photographers. In this post I will introduce the first part of my (former) workflow to you in order to show you an interesting discovery.
My (former) workflow began like this:
Mainly, i shoot raw. Not because my camera does not make decent jpegs, but i like to be in control. I have a directory structure for my photos (actually, there are two, one for the original files, and one for the derivative files. I store them separately), what is extendible, and makes backing up to dvd-s easy, and i want applications to adapt to my habits (workflow) rather then force me to adapt to theirs.
After downloading the photos from memory card (or, as it is often in my case, from a portable hard drive, with built in card reader to wich i have copied the contents of my card on site) and immediately backing them up to a separate hard drive, i convert the raws to DNG-s.
There are web-wide arguments on DNG, if it is the answer or not to the question of the (photographic) life, the (photographic) universe and everything, and a very long but very interesting conversation on it (from Stuart Nixon, Peter Krogh, Kevin Connor, and others) can be found on openraw.org.
Why I have chosen DNG? Portability. Oh yes, i forgot to tell you, my wokflow was developed with portability, and application independence in mind.
Raw converters never write to the raw files. The raw files are from-camera originals, and shall remain so. Usually they are closed, not documneted standards, an in order not to corrupt them, raw-editors do not write them. They usually create a separate file, wich contains the alterations the user have made. And every raw-converter does it on its own way (even the tools the raw converters offer differ slightly). They even place theese files differently (some of them place them to the folder of the image files, while others make a separate directory), and none of them can read the sidecar files of the others (naturally ;-) ). If you have processed a photo with one type of converter, you won’t be able to view the result later on a different converter.
The only exception is DNG. DNG stores the original raw file + metadata about this file in a container. The metadata is about the alterations the user made (in a standardized form) and data on the photo (exif, iptc, xmp, and whatewer). And it is an open standard. Not a perfect one, but usable. And the applications, that implement the standard can read, interpret and write the DNG files (writing means altering the metada about the original embedded raw file, and not directly altering the embedded original raw file).
There is no DNG converter for linux yet (afaik), mostly because linux users (and developers) see the DNG move as a blatant attempt to take over the RAW format market by a jealous software house not currently a player (writing the two words ‘DNG’ and ‘linux’ to google, the first result will be this article).
So far, the only solution – in my view – is DNG. OpenRAW is a very respectable movement, but please, the article that pops up if you go to the openRaw site is 15 months old! And – again afaik – open documentation of the raw formats will not solve the problem of the sidecar files (and thus application independence). Even if a raw file is documented, it does not contain a place for additional metadata (on image alterations). And a little addition: The original title of the above linked article, the Notes on the future of Open RAW formats, and a look at DNG was “DNG is not the answer”, but it was renamed a few days after its publishing. And as the comments after the article shows, Mr Nixon stated things that were wrong, and were rather his assumptions than facts. Now who is blatant here? (more on what was right and wrong in that article and in its comments is here and here by Barry Pearson, (the page was checked for its accuracy by Juergen Specht from openRAW))
I feel that for the members of the openRAW, DNG is the Antichrist, while Adobe is the Satan itself. In my view, the purpose of the two initiations have several common points. DNG has a versioning system, and maybe if members of openRAW would suggest alterations on DNG, then the next release of DNG (if Adobe would have implemented theese theoretical alterations) could be “the” openRAW. DNG is very well accepted, and together, Adobe and openRaw would be able to persuade more manufacturers to implement a common standard.