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ORF to RAW Converter

Convert ORF to RAW in your browser. You download a Linear DNG (.dng), not a .raw: only a camera can create a genuine RAW, and every editor that opens RAW also opens DNG. Nothing is uploaded.

  • Processed locally
  • No upload, no wait
  • No sign-up
  • No watermark

Drop images here

or choose files · paste with Ctrl/⌘ V

RAW expected · other image formats also work

Files are processed on this device. Nothing is uploaded.0 B uploaded

How to use ORF to RAW

  1. 1

    Add your ORF files: drop them here, choose them, or paste from the clipboard.

  2. 2

    There is nothing to tune: the DNG is written uncompressed. Resizing and rotating are under More options if you need them.

  3. 3

    Click Convert. Each file is decoded and encoded in a background thread on this device.

  4. 4

    Download the .dng files one at a time or together as a ZIP.

Why use Aback Images for orf to raw

Where a RAW would go

RAW files are opened by Lightroom, Photoshop Camera Raw, Capture One, darktable, RawTherapee and dcraw-based tools, and every one of them opens the DNG too.

DNG next to ORF

The DNG stores the camera preview's pixels uncompressed, so it can be as large as the 12 to 30 MB raw file, or larger, depending on the preview's resolution.

No new artefacts

The preview inside the ORF is a camera JPEG; the DNG stores its decoded pixels uncompressed, so this step adds no compression damage of its own.

Processed on your device

Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.

ORF vs RAW

What changes from ORF to RAW

Encoding: the ORF uses losslessly compressed sensor data, with a preview and thumbnail; RAW uses uncompressed, lossless JPEG or vendor-specific coding of the sensor data, depending on the maker, and the download is a Linear DNG: demosaiced 8-bit RGB with the colour matrices raw editors need.

Bit depth: 12 bits per channel in the ORF; RAW allows 12 to 16 bits per channel, and the DNG written here has 8 bits per channel, linearised. The sensor's 12 bits are not used: the 8-bit camera preview is converted.

Colour: camera RGB from a Bayer mosaic in the ORF; RAW supports camera-native RGB from a colour filter mosaic, written here as 8-bit sRGB.

Metadata: the ORF can carry EXIF and Olympus maker notes, which also contain the preview; RAW can carry EXIF and vendor maker notes, almost always with an embedded JPEG preview, but nothing is copied across.

About ORF

ORF is the raw format of Olympus and OM System cameras, built around Four Thirds and Micro Four Thirds sensors. It stores 12-bit sensor data with a JPEG preview kept inside Olympus's maker notes.

ORF looks like TIFF but replaces the version number 42 with the letters 'RO', so a little-endian file starts 'IIRO' and generic TIFF readers reject it. Its JPEG preview is not in the main image directory but inside the camera-settings block of Olympus's maker notes.

ORF files usually come from Olympus E-series DSLRs, OM-D and PEN mirrorless cameras and OM System bodies.

About RAW

Camera RAW files (CR2, CR3, NEF, ARW, DNG, ORF, RW2, RAF and others) hold the unprocessed sensor data from a camera along with an embedded full-size JPEG preview rendered by the camera.

.RAW is an extension rather than one format. Panasonic and Leica compacts wrote TIFF-like .RAW files before Panasonic moved to RW2, and scanners and scientific cameras use .raw for headerless dumps with no width, height or layout recorded, which nothing can read without being told those values.

RAW files come from older Panasonic and Leica compacts that saved .RAW, and scanners or scientific cameras that use the extension for pixel dumps.

When converting ORF to RAW makes sense

Forms and workflows that ask for RAW usually feed a raw editor, and each of those opens DNG as well, so the DNG can take the RAW's place. Keep the ORF if you only need to view or share the picture.

What RAW offers when it comes straight from the camera: Maximum editing latitude in RAW editors; Includes a camera-rendered preview. Its drawbacks: Huge files; Every brand uses its own format; Phones, browsers and websites cannot display it.

Limitations

  • The preview inside the maker notes is found by scanning the whole file, and that preview is what gets converted.
  • High Res Shot files combine several exposures in camera; the preview shows the combined result at its stored size.
  • The DNG holds the decoded 8-bit pixels, so it adds no dynamic range or detail beyond the ORF.

Frequently asked questions

Why do I get a .dng file instead of a .raw?

A real RAW is written by a camera and holds the sensor's own readings (12 to 16 bits per channel, stored as uncompressed, lossless JPEG or vendor-specific coding of the sensor data, depending on the maker) along with EXIF and vendor maker notes, almost always with an embedded JPEG preview. This converter reads the JPEG preview inside the ORF, not its sensor data, so it cannot make one either. The Linear DNG you get instead is Adobe's open raw format, and every editor that opens RAW files opens it with the same raw controls. It holds decoded pixels, so it adds no quality or dynamic range.

Are my images uploaded anywhere?

No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.

Can I process many files at once?

Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.

Is it free? Is there a file limit or watermark?

It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.