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Sony ARW raw files that will not open on a Mac

· 6 min read

A Sony ARW file that will not open on a Mac is rarely broken. macOS learns raw formats one camera at a time, through system updates, so an ARW from a body released after your version of macOS, or saved with a raw setting it does not handle, can show a thumbnail in Finder and still refuse to open in Preview or Photos. Update macOS first, then work down the list below.

Why Finder shows the picture and Preview will not open it

An ARW holds two things: the unprocessed data from the sensor, and a JPEG preview the camera made for its own screen. Finder and Quick Look can display that preview without touching the sensor data. A thumbnail therefore tells you the file is structurally readable. It says nothing about whether your Mac can develop the raw data into a full picture.

Which ARW files cause trouble

ARW is one extension covering many different files. Every Sony camera writes its own variant, and three things decide whether a given file opens.

  • The camera model. Support is added per body. Models with similar names, such as successive versions of one line, are separate entries, and the newest is the one most likely to be missing.
  • The raw file type. Sony’s menus have a RAW File Type setting. Older bodies offer Compressed and Uncompressed. Recent ones add Lossless Compressed, on some cameras in large, medium and small sizes. Those newer kinds arrived years after the format itself, and support for them has not always landed together with support for the camera. One body can produce files that open and files that do not.
  • A short copy. A card pulled early, or a cable bumped during import, leaves a file with a preview at the front and nothing behind it.

Test whether your Mac can decode the file

Preview is the plain test: if the picture opens at full size, the Mac can read it. For a clearer answer, run this in Terminal:

sips -g pixelWidth -g pixelHeight ~/Pictures/DSC01234.ARW

If sips prints the dimensions, the raw decoder worked. If it prints an error, macOS could not decode the file, whatever the thumbnail suggests.

To rule out a short copy, go to the folder with the photos in Terminal and list the smallest files:

ls -lS *.ARW | tail -5

Compressed and Uncompressed ARWs from one camera are all close to the same size, so a file far smaller than its neighbors was cut off. Lossless Compressed files vary with the scene, so only a dramatic difference means anything there.

The fixes, in order

  1. Update macOS. Open System Settings, General, Software Update. Camera support ships inside system updates, and this settles most cases.
  2. Check Apple’s list. Apple publishes a support page of the cameras whose raw files macOS can read. Match the exact model name and read any note beside it.
  3. Use the camera maker’s software. Sony offers free raw software for the Mac that understands its own cameras’ files and exports JPEG or TIFF.
  4. Convert to DNG. A DNG converter turns the ARW into an openly documented raw format, which macOS can usually read without knowing the camera.
  5. Change the setting for next time. If a lossless compressed or reduced-size raw is what fails, switch RAW File Type to Uncompressed or Compressed until you can update the Mac. Setting File Format to RAW & JPEG gives every shot a JPEG as well.

One shortcut is usually missing. Some camera brands can develop a raw file into a JPEG inside the camera after the fact. Many Sony bodies cannot, so check your manual before counting on the camera to rescue a shoot.

Converting ARW to JPEG once the Mac can read it

Preview, one photo. Open the ARW, choose File, Export, set Format to JPEG, and save.

Finder, a handful. Select the files, right-click, and choose Quick Actions, Convert Image. Pick JPEG and a size.

Terminal, a folder. In the folder with the photos, run:

for f in *.ARW; do sips -s format jpeg -s formatOptions 90 "$f" --out "${f%.*}.jpg"; done

Manatee, a whole shoot. Manatee converts a folder in one drop. Open it, choose Convert, drop the folder in, and pick JPEG, PNG, HEIC or TIFF. Each result is written as a new copy beside its original, and the ARW is never modified. Nothing is uploaded; it runs on the Mac. It is free for 24 hours with every feature, then $9 once.

Two honest limits. Do not count on any converter, Manatee included, to read a camera that is newer than the software knows. If a file fails in Preview, sort out support with the steps above, or try one file during the free 24 hours before relying on it for a shoot. And Manatee is not a raw editor: there is no exposure slider and no white balance control. How to convert raw photos to JPEG on a Mac compares the routes in more depth.

Why the JPEG looks different from the camera’s screen

The picture on the camera’s screen, and any JPEG the camera saves, has the camera’s own processing applied: the Creative Look or Creative Style you chose, plus its contrast and noise settings. The raw data has none of that. macOS develops it with a neutral default, so the result often looks flatter and less saturated than you remember.

Nothing is broken. For the camera’s look, use the maker’s software, which can apply the same styles. A photo that looks dull after converting it covers the other reasons color shifts in a conversion.

When the file really is damaged

If the maker’s software refuses the file too, or it is far smaller than the others, you are past a support problem.

  • Copy it from the card again, with a different reader or cable if you have one. Do not format the card until every file has been checked.
  • Try to save the preview. In Terminal, qlmanage -t -s 2000 -o ~/Desktop DSC01234.ARW writes a PNG of whatever Quick Look can show, up to 2000 pixels wide.
  • Be realistic about repair. Manatee’s Repair mode is built for corrupt video, PDF and Word documents, not raw photos, so it is not the answer here. Sensor data that was never written to the card cannot be rebuilt by any tool.
  • Manatee does not recover photos that were deleted from a card. It works on files that still exist.

Whether a corrupted photo can be repaired sets out what to expect.

Questions

Why do ARWs from my older Sony open when the new camera’s do not? Support is per model. The older body was added to macOS years ago. The new one arrives in a later update, or has not been added yet.

Which RAW File Type is the safest to shoot? Uncompressed is the most widely readable and the largest. The long-standing Compressed type is also broadly supported and much smaller. The lossless and reduced-size kinds are the ones to test with your own software before an important shoot.

Should I keep the ARW files after converting? Yes. A JPEG is a finished rendering with much of the sensor’s latitude discarded. Keep the ARW as the original and treat the JPEG as the copy for sharing.