The Digital Negative (DNG) Specification describes a non-proprietary file format for storing camera raw files that can be used by a wide range of hardware and software vendors. DNG is an extension of the TIFF format, and is compatible with the TIFF-EP standard.
This version was published in February 2005 and corrected the flaws in the first version. It has proved capable of representing raw images for a large variety of cameras (both when written in-camera or via conversion from other raw image formats) for a few years, and it is the version still typically written in-camera.
11/2023 (v.116)- New MIME type identifier 'image/dng' added and max offset of EOF internal signatures increased to 128000. Submitted by Brigham Young University.
Details: File format summary
: detailed report on file format 
Digital Preservation Department / The National Archives
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