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Converting current RAW images to Open RAW

Please pardon my ignorance if this has been covered somewhere and I just didn't notice it.

I was wondering if there's anything in the works as far as software for converting existing RAW images into an open format? An open format right from the camera would obviously be great, but it does nothing to solve the problem of aging RAW files that may lose support in the future.

I don't know what kind of technical problems exist for this kind of software, but it seems to me that it could be made as a batch processing plugin for UFRaw. Add in the ability to do lossless compression and you'd have something that's quite practical for backup purposes.

While I'm dreaming, let's throw in the ability to create a portable RAW file, something that's reduced in detail to get the file down to under 2mb that could be more easily distributed over the web.

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DudeMan – Sat, 2007/02/03 – 6:20am

The whole topic is a can of

The whole topic is a can of worms, you are entirely correct about it.

Barry is unfortunately not consistent with his comments, and his advise is dangerous, because he tries to convince people that the DNG format is the solution to the 'undocumented RAW formats' and that deleting your original RAW's is save.

However, if you look into the current Adobe DNG specs, you find this warning there:


It should be noted that the Adobe DNG Converter will not necessarily maintain all of the private metadata in certain camera-specific raw formats because this informa- tion is not publicly documented and therefore not available to Adobe. However, the Adobe DNG Converter will maintain all of the original image data as well as all of the metadata needed for a high-quality final conversion. Arguably, the private metadata is not really archival, regardless of the format used, simply because it is undocumented. Nevertheless, Adobe recommends that, when photographers use the Adobe DNG Converter for archival purposes, they should maintain both the resulting DNG file and the original camera-specific file. The DNG file offers greater assurance of longevity, but the camera-specific file may contain more metadata. This distinction does not exist, however, for DNG files created by camera manufacturers because they can include all of the private metadata within the Digital Negative.

The source: Introducing the Digital Negative specification: Information for Manufacturers (PDF, Page 5)

So we have the same chicken/egg problem here also for DNG, it cannot convert all meta-data, because they are not documented, ergo there cannot be a lossless conversion from one file format to the other, if the data which should be converted is not understood.

To your other question, the RAW file is comparable to your analog negative. If you keep your negative for 10 years and then develop a print with the newest chemicals and papers, it will look way better than it was possible 10 years ago.

The same with digital RAW files. Since 7 years I store all my Nikon NEF files as 'straight from the camera' and as converted JPG files with the current RAW converter. If I today look back at the 7 year old JPG conversations and compare them with a todays conversion of an actual RAW file, I can squeeze way more detail out of the same RAW files than I was able 7 years ago.

So its good advise to keep your RAW files and NOT delete them, you will bite yourself if you value your photos and do so.

And note, even Adobe advises against it.

Juergen Specht – Sat, 2007/02/10 – 11:16am
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