PEF Format Guide

Available Conversions

About PEF Format

PEF (Pentax Electronic Format) is Pentax's proprietary RAW image format used in Pentax digital SLR and mirrorless cameras, now manufactured by Ricoh Imaging Company following the 2011 acquisition of Pentax by Ricoh. As a RAW format, PEF files contain minimally processed data captured directly from the camera's image sensor, preserving all the information recorded at the moment of exposure without the quality loss associated with in-camera JPEG processing. Unlike compressed formats that discard image data, PEF files store complete sensor data along with extensive metadata about camera settings, lens information, white balance, Custom Image settings, and shooting conditions. This gives photographers maximum flexibility for post-processing adjustments to exposure, white balance, color grading, contrast, sharpening, and noise reduction without quality degradation. PEF files are based on the TIFF specification with Pentax-specific extensions and use lossless compression, typically resulting in file sizes ranging from 15 to 30 MB per image depending on the camera's resolution. Pentax cameras are particularly renowned for their rugged weather-sealed construction, in-body Shake Reduction (SR) stabilization system, and innovative computational photography features like Pixel Shift Resolution (combining multiple shifted exposures for up to 4x resolution improvement) and advanced astrophotography capabilities including GPS-based Astrotracer for tracking stars during long exposures—all of which are preserved in PEF files for optimal post-processing.

History of PEF

Pentax, founded in 1919 as Asahi Optical Joint Stock Co. in Japan, has a storied history in optical engineering and photography, becoming famous for their Spotmatic film cameras in the 1960s and pioneering the K-mount bayonet lens mount in 1975 with the Pentax K1000—a mount that remains in use today, providing unparalleled lens compatibility spanning nearly 50 years. Pentax entered the digital age relatively early and introduced the PEF format with their digital cameras in the early 2000s. The Pentax *ist D, launched in 2003, was Pentax's first digital SLR and marked the beginning of their digital K-mount legacy, producing PEF files from its 6.1-megapixel CCD sensor. The camera was notable for being one of the smallest DSLRs available at the time and maintaining compatibility with decades of K-mount lenses. The *ist series evolved through models like the *ist DS (2004), one of the world's smallest DSLRs, and the *ist DL (2005), bringing digital photography to enthusiasts. In 2006, Pentax launched the K-series starting with the K100D and K10D, introducing their groundbreaking Shake Reduction (SR) in-body image stabilization system, which stabilizes any lens mounted to the camera—a significant advantage over competitors who required stabilization built into each lens. The K10D (2006) gained a strong following among enthusiasts for its weather sealing, excellent build quality, and outstanding image quality, establishing Pentax's reputation for ruggedness. Throughout the late 2000s and early 2010s, the K-series expanded with models like the K-7 (2009), K-5 (2010), and the professional-oriented K-3 (2013), all producing PEF files and incorporating progressive improvements to sensor technology, weather sealing, and ergonomics. In 2011, Pentax was acquired by Ricoh, forming Ricoh Imaging Company, which continued the Pentax camera brand. A watershed moment came in 2016 with the launch of the Pentax K-1, the company's first full-frame DSLR, which integrated features like Pixel Shift Resolution (combining four pixel-shifted exposures for true-color 36MP images), advanced astrophotography modes, and GPS-based Astrotracer (using the SR system to track stars). The K-1 Mark II (2018) refined these capabilities further. Pentax also developed the K-70 (2016) and KP (2017) for enthusiasts, emphasizing weather sealing, high ISO performance, and portability. Throughout this evolution, the PEF format advanced to support higher resolutions, Pixel Shift Resolution data, HDR capture, and compatibility with Adobe DNG format (many Pentax cameras can save RAW files as DNG in addition to PEF). The format gained support from RAW processing software including Adobe Lightroom and Photoshop, Capture One, DxO PhotoLab, and Pentax's own Digital Camera Utility software. While Pentax maintains a smaller market share compared to Canon, Nikon, and Sony, the brand has cultivated a devoted following among photographers who value rugged build quality, in-body stabilization, unique features like Astrotracer, and the extensive K-mount lens ecosystem.

Key Features and Uses

PEF files store unprocessed, linear sensor data in 12-bit or 14-bit depth (depending on camera model and settings), preserving significantly more tonal information than 8-bit JPEG files—14-bit PEF files capture 16,384 tonal levels per color channel compared to JPEG's 256 levels. Modern Pentax sensors capture excellent dynamic range of 13-14 stops, providing substantial latitude for recovering shadow and highlight detail in post-processing. PEF files include comprehensive EXIF metadata containing all camera settings: shutter speed, aperture, ISO sensitivity, focal length, lens identification (including legacy manual lenses via lens data input), autofocus point selection, metering mode, Custom Image settings, and Digital Filters applied. The format stores the Bayer array color filter data from the sensor, allowing photographers to adjust white balance after capture without penalty, unlike JPEG where white balance is permanently applied during processing. PEF files preserve Pentax's advanced shooting mode data: Pixel Shift Resolution exposures contain the individual shifted frames allowing reprocessing of the super-resolution composite; HDR capture files include bracketing data; astrophotography modes embed GPS and star tracking information from the Astrotracer system. The format includes Pentax-specific lens correction data, allowing automatic correction for distortion, vignetting, lateral chromatic aberration, and diffraction specific to each lens—particularly valuable given the vast K-mount lens ecosystem spanning decades with varying optical characteristics. PEF supports Pentax's Creative Palette system and Digital Filters, storing both the RAW data and the applied processing parameters, allowing photographers to adjust or remove effects in post-processing while preserving the original sensor data. Many Pentax cameras offer the option to simultaneously save files in both PEF and Adobe DNG format, providing flexibility for workflows requiring the open DNG standard while maintaining Pentax-specific metadata in PEF files.

Common Applications

PEF files are essential for photographers using Pentax and Ricoh cameras across various photographic disciplines, particularly those who value the brand's unique features and ruggedness. Landscape photographers are strongly drawn to Pentax for the combination of excellent weather sealing (available even in entry-level models), in-body Shake Reduction stabilization (working with any lens including vintage glass), and innovative Pixel Shift Resolution mode that produces extraordinary color accuracy and detail by capturing true RGB data at each pixel location—features that make PEF files invaluable for producing large prints with maximum quality. Astrophotographers particularly favor Pentax for the GPS-based Astrotracer system (available in K-1, K-1 II, K-3 III, and other models), which uses the in-body stabilization mechanism to precisely track stars during exposures up to several minutes, eliminating star trails without requiring bulky equatorial mounts; these PEF files contain critical GPS and tracking metadata for analyzing and refining astrophotography workflows. Outdoor adventure photographers rely on Pentax's legendary weather sealing and durability, shooting PEF files in harsh conditions—rain, snow, dust, extreme temperatures—where other camera systems might fail, particularly valuing models like the K-1, K-3 series, K-70, and KP that are built to military specifications. Travel photographers appreciate the combination of in-body stabilization (which works with compact prime lenses), weather protection, and the extensive K-mount lens ecosystem including many compact and affordable options, capturing PEF files that preserve maximum quality while working with lightweight kits. Street photographers value Pentax's unobtrusive design and excellent ergonomics, shooting PEF files with classic manual focus lenses from the decades-long K-mount history, benefiting from focus peaking and in-body stabilization with vintage glass that would be unstabilized on other systems. Architecture and real estate photographers use PEF files with Pentax's shift lenses (notably the smc PENTAX-D FA645 28-45mm) and the K-1's unique built-in perspective control feature that uses the sensor shift mechanism for electronic movements, simulating a traditional view camera. Macro photographers leverage Pentax's excellent in-body stabilization and focus peaking, shooting PEF files with K-mount macro lenses or adapted legacy macro glass, often using focus bracketing features for focus stacking workflows. Portrait photographers working in outdoor or unpredictable environments benefit from Pentax's weather sealing and reliable operation, producing PEF files with excellent color rendering and the flexibility to work in challenging conditions. Fine art photographers appreciate the Pixel Shift Resolution technology for museum-quality prints, shooting PEF files that extract the absolute maximum resolution and color accuracy from the sensor, particularly valuable for still life, product photography, and reproduction work. The Pentax user community, though smaller than Canon/Nikon/Sony, is notably dedicated and technical, with many photographers specifically choosing Pentax for features unavailable elsewhere: Astrotracer for astrophotography, universal lens stabilization, rugged construction, and excellent value.

Advantages and Disadvantages