PEF

Less so. PEF has no public specification, but it has been thoroughly reverse-engineered over two decades, giving it broader and more stable third-party support than several other niche manufacturer raw formats.

Yes, partly. Many Pentax and Ricoh GR-series bodies include a built-in DNG shooting mode, letting photographers capture directly in DNG instead of PEF and skip the conversion pass entirely for those files. That option is unusual among manufacturer raw formats and reflects Pentax's comparatively pragmatic approach to archival compatibility. Images already captured as PEF, however, still need converting to keep a DAM library on one consistent raw standard.

PEF stores 12-bit or 14-bit Bayer sensor data inside a TIFF-based container, compressed with a lossless scheme so no sensor information is discarded while keeping files smaller than an uncompressed capture. Alongside the raw data, PEF carries standard EXIF fields, Pentax-specific maker-note metadata such as lens ID and in-camera correction settings, and an embedded JPEG preview for quick viewing.

Pentax introduced PEF in February 2003 alongside the *ist D, its first digital SLR camera. Like most manufacturer raw formats from that generation, PEF was built on a TIFF skeleton to store the sensor's unprocessed Bayer readout, and it has remained Pentax and Ricoh's native raw format for digital cameras in the more than two decades since.

Yes. Even though two decades of reverse engineering mean Adobe Camera Raw, libraw, RawTherapee, and darktable all decode PEF reliably today, converting incoming PEF files to DNG — or favoring the camera's native DNG shooting mode where available — still keeps a photo library on one consistent archival raw standard. That avoids depending indefinitely on continued maintenance of per-manufacturer decoders, which is a narrower guarantee than a single openly documented format like DNG provides.

Pentax Digital Camera Utility is the manufacturer's own raw converter for PEF files, published by Ricoh Imaging since its acquisition of the Pentax brand. The software was formerly built on Silkypix decoding technology. It sits alongside broader third-party support: Adobe Camera Raw and Lightroom Classic read PEF natively on Windows and macOS, while RawTherapee and darktable decode it via the open-source libraw library.

dcraw, the long-standing open-source command-line raw decoder, has supported PEF for most of the format's history, and libraw — the library derived from dcraw's decoding work — extends that support into many later scripted and batch-processing tools. Together they let DAM systems and automated pipelines read PEF files without relying on a GUI application such as Adobe Camera Raw or Pentax's own converter.

Ricoh Imaging owns the Pentax brand and the PEF format today. Ricoh acquired Pentax's imaging business from Hoya in 2011, after Hoya itself had bought the Pentax camera division from Pentax Corporation in 2008. Ricoh has continued using the Pentax name on its DSLR line and its raw converter software, so PEF remains tied to a name whose corporate ownership has changed twice in less than two decades.