DNG (Digital Negative) is Adobe’s openly published raw file format, introduced in 2004 as a universal standard that would remain readable indefinitely regardless of which camera manufacturer’s proprietary format was used to capture it. The format is based on TIFF/EP, includes a full color profile and EXIF metadata, and supports lossless compression. Unlike Canon’s CR2/CR3, Nikon’s NEF, Sony’s ARW, and the other proprietary raw formats, DNG is documented publicly and can be read by any compliant software without reverse engineering.
Some cameras shoot DNG natively, treating it as their only raw format. Leica has used DNG across its M and Q lines for years. Pentax offers DNG as an option alongside its proprietary PEF. Sigma’s fp, fp L, and certain other bodies write DNG. Hasselblad’s H6D and X1D systems use a variant called 3FR but offer DNG export. Smartphone cameras using Android’s Camera2 API (Google Pixel, Samsung Galaxy, OnePlus) typically record raw as DNG, since the format was designed for cross-platform compatibility. Many drone cameras, including DJI’s Mavic and Inspire lines, also write DNG.
For cameras that don’t shoot DNG natively, Adobe Lightroom and the standalone Adobe DNG Converter can transcode any supported proprietary raw format to DNG during import or as a batch operation. The conversion is lossless: every pixel value, the demosaic data, embedded JPEG previews, and the metadata transfer faithfully. Photographers who choose to convert to DNG on import typically cite three reasons: smaller file sizes (DNG’s lossless compression is often 10 to 20 percent more efficient than CR2 or NEF), a single workflow file format across multiple camera bodies, and futureproofing against the day a manufacturer abandons a proprietary format.
The futureproofing argument has real precedent. Kodak’s KDC, Minolta’s MRW, and several early Pentax raw formats have effectively been abandoned by their original tools, leaving photographers reliant on third-party support. DNG’s open specification means even if Adobe were to disappear, the format documentation would remain available and any developer could write a reader. The Library of Congress and several archival institutions recommend DNG (along with TIFF) as a preservation format for digital photography precisely for this reason.
The format has limitations that prevent universal adoption. Some camera-specific metadata (like Canon’s Dual Pixel raw data, Fujifilm’s film simulation tags, or Sony’s auto-focus metadata) doesn’t always transfer cleanly to DNG, since the spec wasn’t designed around proprietary extensions. The conversion step adds time during import, often doubling or tripling the time it takes to ingest a memory card. And some workflow tools (Capture One in particular) handle proprietary raws faster than DNGs from those same cameras, which can outweigh the file-size and standardization benefits.
DNG supports two key features that proprietary raws often lack: embedded fast load data (a half-size preview optimized for editor scrubbing) and lossy DNG, an Adobe-specific JPEG-like compression that reduces file size by 75 to 80 percent while preserving most raw editability. Lossy DNG is useful for archive workflows where storage cost matters more than absolute pixel-level fidelity. Smart Previews in Lightroom are built on lossy DNG technology under the hood, allowing editing without the original files mounted. For most working photographers, the choice between DNG and proprietary raw comes down to workflow preference rather than image quality, since both produce identical results in non-destructive editing.