What does this format store?+
PEF is Pentax’s native raw image format for compatible cameras. It keeps image data for later development with camera capture information. Some Pentax models also offer DNG as an alternative recording format. These are choices for raw storage, not the same distinction as choosing a finished JPEG for immediate sharing.
How does compression affect quality?+
The K-5 II manual documents PEF/DNG selection. Precision, compression and vendor metadata need the specific camera documentation; do not generalise a single model’s settings to every PEF. A native file may retain manufacturer information that another processing workflow interprets differently.
Should I choose PEF or DNG in the camera?+
Check which choice your model offers and your processor supports. PEF is the native Pentax representation; DNG follows Adobe’s published structure. Test metadata and development before changing an established archive workflow.
What should I check before opening the file?+
Check the exact camera model and recording mode in the processor’s support list. Raw support is model-specific, even when the extension is recognised. Viewing an embedded JPEG preview does not prove the sensor data has been decoded.
What changes when I export to another format?+
Raw-to-image export develops the data: white balance, colour mapping and tone become part of the pixels. Grayscale, palette and SDR targets can discard additional information. Keep the original; converting a rendered image back into a raw container cannot reconstruct the capture.
When is this format useful?+
Use the raw original for repeated photographic development when exposure interpretation and colour decisions need to remain flexible. Export JPEG for an opaque delivery image or a suitable high-precision raster for further editing. Those exports bake in processing choices and cannot recreate the original sensor data, calibration or all vendor metadata.