Mac OS Photos freezes when editing an Raw file (on Mac OS 15.8)

Thank you Léonie,

My libraries are non-system photo libraries and local stored in de pictures folder. I still have 300 gb storage. Before the update of last monday there was no problem. There are no apps hanging or hogging the memory. Quiting apps and safe mode doesn't work either:

Title:

Photos permanently hangs / crashes when editing Nikon NEF RAW files on macOS 15.8 (24H23)

Summary:

Since updating to macOS 15.8 (24H23), the Photos app either permanently freezes or crashes when opening a Nikon NEF RAW file (Nikon Z6III) in edit mode. This did not occur prior to this update. Two distinct failure modes have been captured, both pointing to instability in the same underlying render pipeline.

System information:

• Model: iMac19,1 (2019, Intel)
• GPU: AMD Radeon Pro 570X (discrete)
• OS: macOS 15.8, Build 24H23
• Photos version: 10.0 (770.0.177)
• Camera: Nikon Z6III (.NEF files)

Steps to reproduce:

1. Open Photos
2. Select a RAW photo (.NEF, Nikon Z6III)
3. Click "Edit"
4. In normal mode: a loading indicator appears in the bottom-right of the image and never disappears; the UI freezes completely and stops responding to input
5. In Safe Mode: instead of freezing, the app crashes outright (see attached crash log)

Ruled out during troubleshooting:

• Not related to iCloud Photo Library sync (tested with local, non-system libraries)
• Not related to Photos extensions (disabled — issue persists)
• Not related to network/firewall software
• No elevated CPU or memory usage observed during the freeze (this is a blocking wait state, not a compute-bound issue)
• Reproducible across multiple, separate local photo libraries
• Worked correctly prior to updating to 15.8

Failure mode 1 — Freeze in normal mode (process sample attached):

A process sample taken during the freeze shows the main thread blocked in a synchronous dispatch call:

-[PAItemController isEditing] → dispatch_sync

waiting on the NUCGImageSourceNode background thread, which is itself blocked on a mutex inside Apple's RawCamera decoder plugin:

IIOReader_RawCamera::callUpdateSourceProperties
  → CGImageSourceAddProperty
    → _pthread_mutex_firstfit_lock_wait
      → __psynch_mutexwait

This indicates a deadlock inside the RawCamera plugin (ImageIO framework) while reading/adding metadata properties from the NEF file — no CPU usage is observed because the thread is blocked waiting on a lock that never releases.

Failure mode 2 — Crash in Safe Mode (crash log attached):

In Safe Mode (reduced GPU acceleration / disabled kernel extensions), the same operation instead triggers a hard crash via an internal assertion in the NeutrinoCore render pipeline:

-[NURenderer renderImage:rect:toDestination:atPoint:error:]
  → _NUAssertFailHandler
    → -[NUAssertionPolicyAbort notifyAssertion:]
      → abort() (SIGABRT)

Crashed thread: NUJobQueue.Interactive_Render.run. This is a deliberate internal safety abort — Photos' own code detects an invalid/inconsistent state in the render pipeline and intentionally terminates rather than continuing with corrupted state.

Analysis:

Both failure modes point to instability in the same rendering path when processing this Nikon NEF RAW data — likely triggered by processing of maker-note/EXIF metadata during RAW decode combined with GPU-accelerated rendering (NeutrinoCore/Core Image). Under normal GPU-accelerated rendering, this manifests as a deadlock; under Safe Mode's reduced rendering path, it manifests as an assertion crash instead. The discrete AMD GPU (Radeon Pro 570X) may be a contributing factor, as this class of render-pipeline issue is more commonly seen on Intel Macs with discrete GPUs.

This is very good advice that will undoubtedly help a lot of people, especially those who installed update 15.8.0, which completely broke the preview system (Preview / Quick Look). Trying to preview any RAW file causes Finder to become completely unresponsive, making it impossible to perform basic tasks such as copying files. In that situation, it's essential to do exactly what you recommend. Or they can install 15.8.1, which largely fixes the problem. But then they must make sure not to install 15.8.2, which reintroduces the issue.

Apple bug in 15.8. Please report it in Feedback Assistant or call support. Hopefully they fix it.

https://forums.macrumors.com/threads/warning-macos-15-8-0-update-may-break-camera-raw-support.2489538/?post=34801032#post-34801032

https://www.dpreview.com/forums/threads/macos-sequoia-15-8-problems.4867284/

https://www.reddit.com/r/MacOS/comments/1whvkwz/bug_macos_1580_update_may_break_camera_raw_support/

the RAW files are a lot larger than the JPEGs.

Could it be that your Mac is low on storage?

Or some app may be hogging the memory.

Have you tried to quit all other apps and restart your Mac before editing the RAW files to prevent memory pressure?

Where is your Photoslibrary stored? Are you keeping it in your Pictures folder, the default location? Or is it on an external drive? If the library is on an external drive, try to edit a RAW file in a new test photos library in your Pictures folder. Can you edit your RAW files when they are on your internal drive? See:

Create additional libraries

Keep sending bug reports to Apple.

But check systematically for issues on your Mac, that could cause freezing, like lack of storage, memory pressure, a damaged photo library, referenced originals, or keeping the Photos Library on an unsupported external drive.

That is a thorough summary.

Apple's RAW Support list has a footnote for the Nikon Z 6III: ⁴ Lossless RAW format only

You have set the camera to lossless RAW format?

Which camera model is your Canon camera?

léonie, it is an Apple bug in the 15.8 update. It has nothing to do with unsupported formats (which didn't cause these issues when it worked anyway). See the Macrumors thread linked above, there are many people experiencing this with many cameras and formats.

Apple needs to fix this.

macOS 15.8.1 fixed the problem. macOS 15.8.2 reintroduced it. "Great job", Apple!

macOS 15.8.1 is a security update, so it is essential to install it, asap:About the security content of macOS Sequoia 15.8.1 - Apple Support (CA)

I have not yet seen an announcement for the security content of 15.8.2.

Same here. Upgraded my M1 MacBook pro from 15.7.7 to 15.8.

Since then chaos. No image thumbnails in finder for at least 98% of my files. Preview hangs itself when opening a CR3 file. No thumbs for any CR3 files.

Restarting the system or finder or the Quicklook process or whatever has at best added thumbnails to a hand full of files if that folder was open at the time.

It's a disaster and apple needs to fix this. I submitted feedback and of course it automatically says nothing similar was reported. Haha.

Internet is full of people having trouble.

At least my Mac mini 2018 Intel is still at macOS 15.8.1 and no 15.8.2 update is available (or maybe you grabbed it just before it was cancelled).

Are you perhaps using M series Mac or Sequoia 15.8.2 beta?

Exact same issue macbook Pro M4, freshly updated to 15.8.

Also finder freeze when I try to quickview on .arw files (sony raw)

Still getting this issue in 15.8.2

Preview crashes when trying to open .dng

Photos crashes when trying to import .dng