What does this format store?+
ORF is Olympus Raw Format, used for raw capture in compatible Olympus and OM System workflows. It retains capture data and camera information before final photographic rendering. The Olympus E-1 manual distinguishes ORF from JPEG, describing raw data without applied white-balance and contrast processing.
How does compression affect quality?+
OM System describes no compression or lossless compression depending on camera. Precision and interpretation are model-specific; do not assign one universal bit depth from the extension. The rendered preview can reflect camera settings that remain adjustable during raw development.
Why can an ORF look different from its preview?+
The preview is already rendered. A raw processor chooses its own colour profile, white balance and tone settings, so its developed pixels can differ without changing the original sensor data.
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.