Camera raw

Clarification: many writers refer to the "RAW format" or "Camera RAW" in the literature and on Web pages. RAW is not a image file format; it is a generalization for formats, open or propriety, that encoded all the image data captured by a camera's sensor without in-camera processing. Canon's .CR2, Nikon's .NEF, and Pentax's .PEF are examples of proprietary file formats. The use of upper case letters suggests that it is a file format, thus lower case is used herein.

"Understanding Digital Raw Capture"
Adobe Whitepaper by Bruce Fraser, copyright 2004.

Adobe "Camera Raw" plug-in, first released in February 2003


Tag Image File Format / Electronic Photography (TIFF/EP) is a digital image file format standard – ISO 12234-2: "Electronic still-picture imaging – Removable memory – Part 2: TIFF/EP image data format." This is different from the Tagged Image File Format, which is a standard administered by Adobe currently called "TIFF, Revision 6.0 Final – June 3, 1992".

Adobe DNG

Adobe DNG is a file format (.DNG) for digital photographs based upon TIFF/EP, with a open (published) specification. Adobe developed the DNG ("digital negative") file format in response to issues associated with camera manufacturers' proprietary digital image file formats. DNG is a subtype of TIFF 6.0. Some cameras offer the ability to save work in-camera as DNG files; many photographers convert images into DNG from a camera native file format to avoid the proprietary issues associated with a manufacturer's file format. There are two potential appeal to archives: the ability to convert all digital images file to one format (normalization), and the option to embed raw files into the DNG during conversion.

Three types of DNG:

Linear DNG
Cinema DNG.

DNG Specifications

"Introducing the Digital Negative Specification." Adobe whitepaper (2005)
Digital Negative (DNG) Specification (Version, February 2005)
Digital Negative (DNG) Specification (Version, May 2008)
Digital Negative (DNG) Specification (Version, June 2009)
Digital Negative (DNG) Specification (Version, June 2012)

General Information on DNG

Barry Pearson's DNG website contains a wide range of information about the development of DNG.
The NDIIP webpage on DNG only presents information on Specification 1.1.


JPEG2000 Website

JPEG 2000 in Archives and Libraries Interest Group

There are two websites for this group
  • The original webpage associated with American Library Association (ALA) Connect containing minimal information dating from 2010; and
  • The current website with its affiliation to ALA's Library and Information Technology Association (LITA)

The charge of the LITA JPEG2000 group is to "Support education, development, and advocacy activities for the adoption of the jpeg 2000 image standard in archives and libraries."

"Although members of the library and archives communities were not explicitly involved with the creation of the new standard, the characteristics of JPEG2000 files are of great interest. JPEG2000 is not only an evolutionary progression of formats but also as a revolutionary step that changes best practices in ways that can sustain the profession for a long period of time."


OpenRAW was a movement begun on 25 April 2005 by a group of photographers to address the growing problem of proprietary image file formats. The groups objective was “Digital Image Preservation Through Open Documentation.” The stated goal of OpenRAW was "to encourage image preservation and give creative choice of how images are processed to the creators of the images. To this end, we advocate open documentation of information about the how the raw data is stored and the camera settings selected by the photographer." The efforts of the OpenRaw group splintered, however, and the group ended approximately a year after its formation.