Most high-end digital cameras offer users the option of downloading their images in RAW format. Using RAW allows photographers to preserve the maximum amount of original image data and maximum control over image processing. RAW conversion software (like Bibble, Silkypix, Adobe Camera Raw, and Capture One) allows photographers to adjust exposure, white balance, noise reduction, sharpness and other elements after the exposure is made. It eliminate the potentially negative artifacts of in-camera processing.
RAW format would be the ideal archival format for digital images if a single, open standard could be established by camera manufacturers. Unfortunately, they have developed their own proprietary RAW formats (currently over 200!), each one storing images and organizing raw image data in a unique way. This has made things difficult for RAW conversion software companies, who must constantly adapt their products for particular models, but even more so for serious photographers and institutions who cannot rely on RAW as a means of archiving the original image data that they capture. Already older digital camera RAW formats are not being supported by the latest software.
Due to its “lossless” nature and because it is widely supported by image-manipulation applications, TIFFs have become the preservation format of choice. However, if there were a standard version of RAW, it would be a far more appealing alternative for archiving digital collections. The reasons include:
- Using RAW, artifacts are reduced because no compression is used.
- RAW makes the full dynamic range of a camera’s sensor available for post-processing.
- RAW file sizes are about 1/3 to 1/2 smaller than TIFFs.
- RAW files could be saved “as is.” They would not have to be converted to another lossless format (like TIFF) for preservation purposes.
The need for an open Raw standard is supported by a growing number of individuals, organizations, software companies, and developers. Libraries, archives, museums, and academic institutions should join the call for manufacturers to develop a single digital image preservation format based on open documentation. This would ensure that the capture data for image collections would be in the most original and flexible format possible for the future.
In a comment to the original posting, Barry Pearson notes that, although no open RAW standard currently exists…
“Adobe’s DNG is supported by a growing number of individuals, organizations, software companies, and developers. (And some camera manufacturers). Camera manufacturers themselves won’t cooperate to develop an alternative to DNG.
The place where such a standard belongs is ISO’s TC42 WG18, and they are currently reviewing ISO 12334-2 (TIFF/EP), and examining DNG (which is based on the current version of TIFF/EP) to see what lessons it has for the revision.”
