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When I installed Sierra I also profiled my display (with a spectrometer) and have been using the created icc profiles since then. Both Quick Look preview and the macOS preview app when displaying images will show weird colors though: cutout deep burned shadows! The strangest thing is that on the quicklook preview, the colors will be fine until I zoom in the image: After that it will darken, and never recover (until I reopen the preview).

This behavior happens for images (tested jpg,png and raw) that have an embedded profile, a referenced profile or are not color managed at all. Even with the Screenshots that one can grab with Cmd+Shift+3.

Photoshop and Affinity Photo display colors properly (and rather consistently) on all the above scenarios.

I discovered that it won't happen when the original display profile (named imac) is used, but will happen with all the other profiles, created both by basICColor and ArgyllCMS.

Here's a sample: from left to right, the rendering of the same file in Preview(quick look is the same), Apple Photos App, Photoshop and Affinity Photo

From left to right, the rendering of the same file in Preview(quick look is the same), Apple Photos App, Photoshop and Affinity Photo

Anobody having a clue what is going on? It's been bothering me for months!

Edit (an interesting discovery): I discovered that unchecking "embed color profile" while viewing the Export As.. dialog on Photoshop, exhibits a similar darkening issue that is fixed if I revert my System Preferences to using the default display profile. The file saved is fine though. Probably Adobe is using macOS's previewing capabilities inside their Export As... dialog? I wouldn't know.... Apple Photos app is exhibiting a similar behavior, but the results is not so exaggerated as it is in the preview/quick look tool

Here (on the left) is how QuickLook shows an image when I first open it, and then (on the right) when I double tap (with my magic mouse) to cause it to zoom. When the image is already 1:1 scale like this one, it won't zoom further, but the color weirdness does kick in anyways. Zooming out, doesn't solve the problem. One has to close QuickLook to recover original colors. quicklook destroys colors when zooming

  • well, not sure in what sense you mean "use" ColorSync; could you explain? I keep my icc profiles in ColorSync's folder /Library/ColorSync/Profiles/, also I open the utility at times to check colorspace coverages and check gamma curves of various icc profiles, but not sure in which other way would I be using it. If you mean having loaded an icc profile for my monitor, yes I have via System Preferences Displays – FotisK Feb 5 '17 at 23:41
  • First Aid for the installed icc profiles, returns the same error for every and each user-generated profile: "Header padding is not null." -While I've avoided repairing them for such a minor issue, I think it's worth a try repairing them this time! I'll get back with the results – FotisK Feb 5 '17 at 23:48
  • I did the repair (had to run it a few times since every time another issue would come up - all related to the padding and some invalid unicode characters in the desc string) and finally I reached zero errors. Reloaded my custom profile, relaunched the applications, but no luck. Same problem! – FotisK Feb 5 '17 at 23:54
  • thank you @Mr.Kennedy for the suggestions. I didn't find any name conflict in the /Users/.../Library/ColorSync/Profiles folder. Also I followed the steps for clearing the cache of quicklook (did not perform the last step of manually deleting the plist files since they were not in the same location and were protected on macOS Sierra) – FotisK Feb 6 '17 at 0:57
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    I'd send it to bugreport.apple.com & see what they have to say. I can't repro on El Cap, but my icc files don't error & were probably created by something different [X-Rite in my case] Colours are consistent here in all relevant apps. BTW, apart from the obvious over-blowing in Preview, the 2 examples on the right look a bit under-contrast to me, quite a grey cast to them – Tetsujin Feb 6 '17 at 6:01
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I had this problem with High Sierra, Preview, and a DisplayCal profile.

The latest version of DisplayCal, 3.5, has in its release notes:

Mac OS X: Set default profile type to single curve + matrix with black point compensation due to long-standing Mac OS X bugs with any other profile type.

Upgrading DisplayCal and creating new profiles for each of my displays based on the Default profile solved the problem for me. The profile is probably not as descriptive as it could be, but at least Preview/Quick Look work.

  • Thank you @jkua, I've been following the discussion on the DisplayCal forum but didn't have the opportunity to test the workaround myself - Glad to hear it works! Even though the problem seems to be on Apple's side and should be addressed by them, I'll accept your answer since yur answer is probably the solution for most people coming here! – FotisK Mar 14 '18 at 17:47
4

(After reading all the literature I could find around the issue here's what I've learned)

A disclaimer first

There is a chance (as @Mr.Kennedy points out) that your system is suffering from issues with the quicklook generator. You may wish to read first his very thorough details on clearing the cache and debugging qlamanager's process of generating the thumbnails/previews. If you are certain the actual thumbnails/previews generated are fine, read on!

the Problem

Description of the problem

Apple programs and programs that depend on ColorSync CMM's capabilities, exhibit under some conditions crushed black colors and gamma issues.

Programs affected

  • Preview
  • Quick Look (when zoomed in)
  • Certain versions of Lightroom
  • The Export As... preview at Photoshop (the Save for Web (legacy) dialog is not affected on the other hand)
  • Apple Photos App
  • Apple iPhotos App
  • Aperture
  • Quicktime
  • Finalcut Pro X

(the issues affecting QT, FCPX Lr and Aperture may be different, I'm not sure)

Programs (not) affected

  • Quick Look (before zooming in)
  • Finder previews/thumbnails
  • Adobe Bridge
  • all programs who manage their own colors

Specifics

This is an issue (or a family of issues) around ColorSync. Most probably an Apple's bug inside ColorSync or Preview/QuickLook/Photos, that affects some color profiles generated by a few profiling software, but does not affect other profiles at all (such as the factory profiles).

According to some, first ColorSync issues were introduced in Mountain Lion. Others had issues in Mavericks, while others discovered it first in El Capitan. I can verify that it is still present in Sierra though. It's unclear if all these issues were all one and the same, but in here I'll treat them as such.

Adobe is aware of these issues (it was affecting Lightroom up to some version) rectified it since(2), but consequent updates by apple have complicated things since it has reemerged in a different way. There is a lengthy discussion in the Adobe forums(3).

Cause

At the root, it is that certain ICC profiles, contain information that **Apple's ColorSync won't treat properly (and this affects all programs that rely on ColorSync). There have been various ideas proposed as what it is that ColorSync doesn't like about them. This issue has been linked (but inconclusively) to:

  • LUT based icc profiles
  • matrix based icc profiles
  • particular software used to generated the ICC profile (eg displayCal/basICColors).
  • compatibility issues with the ICC version number (ICCv2 or v4 profiles)
  • black point compensation accounted for in the profile curves.
  • EIZO displays
  • Secondary displays

There has been no consensus though. For instance I've seen both ICCv2 and ICCv4 profiles that work, and ICCv2 and ICCv4 profiles that do not.

Solution

No solution has been found yet afaik.

  • From reports, it seems that profiles created with certain programs seem to be "incompatible" while profiles created by other programs seem to be fine.If you are using

    • displayCal (using ArgyllCMS) (aka dispcalGUI)
    • basICColor
    • Eizo ColorNavigator (4)

    this may be the related. testing some other software for profiling, may be the solution for some who have the option

  • Others have reported success with experimenting by changing parameters of the profiles generated (ICC version number, black point compensation, LUT, curves, 3x3 matrix) but nothing definitive.
  • Adobe is implementing its own workarounds(2),(5) (that seem to be falling apart when apple is changing something).
  • One could revert to using the factory profile (for those who don't care about color management) which work fine
  • Needless to say that avoiding ColorSync reliance and using programs that color manage their own output everywhere in your work environment is certainly the most complete solution (but rarely a viable option)

Raising Awareness

You may also wish to add your voice by submitting to Apple a bug report on the issue

Other places where this problem is discussed

I'm listing here some of the other places where these issues are being discussed

OSX Preview issues

Adobe Lightroom

Finalcut Pro X

1

Here's a primer on ColorSync and Apple's color management. If the following doesn't help resolve the color shift when zooming in on QuickLook previews, then I suggest you submit a bug report to Apple: https://developer.apple.com/bug-reporting/

"The strangest thing is that on the quicklook preview, the colors will be fine until I zoom in the image: After that it will darken, and never recover (until I reopen the preview)."

Have you used the ColorSync Utility? From the Finder Cmd⌘+Shift+u will get you to the /Applications/Utilities/ directory where ColorSync Utility.app lives.

Check for all Quick Look files:
/Library/QuickLook/
/System/Library/QuickLook/
/Users/<user_name>/Library/QuickLook/

Are there any duplicate or conflicting *.qlgenerator files? Also, and per the above article try:

First try running a permissions fix on the boot drive using Disk Utility to ensure that the Quick Look plug-ins and other files the Quick Look server needs are properly accessible, and then force Quick Look to reload the plug-ins and its cache by running the following commands in the Terminal:

qlmanage -r
qlmanage -r cache

After this is done, clear out the Quick Look configuration files by going to the /username/Library/Preferences folder (in Lion press the Option key and select "Library" from the Finder's Go menu), and then removing the files called "com.apple.quicklook.ui.helper.plist," "com.apple.quicklookconfig.plist," and "com.apple.QuickLookDaemon.plist." With these files removed and the Quick Look service reloaded, try previewing your documents again.

Are there any duplicate or conflicting *.icc profiles in
/Library/ColorSync/Profiles/
/System/Library/ColorSync/Profiles/
/Users/<user_name>/Library/ColorSync/Profiles/

It might help if you rebooting - maybe "zap the PRAM" (NVRAM) as well: hold Option+Cmd⌘+p+r and let the computer chime at least three times while restarting then let go of the keyboard kung-fu grip.

Also, per MacIssues.com: check the Cache files in ~/Library/Caches/com.apple.QuickLookDaemon/
~/Library/Caches/qlmanage/

In addition, you can try removing the QuickLook caches manually, which can be done by opening the user library from the Finder’s Go menu (if it is missing from this menu, hold the Option key to reveal it). Then open the Caches folder in the window that appears and locate and remove the folders called “qlmanage” and “com.apple.QuickLookDaemon.” When finished, log out and back in to your system and try using QuickLook again.

Lastly, here are some Apple developers notes for debugging - perhaps the tool qlmanage can help you to ascertain the cause of this problem:

per man qlmanage

1.  qlmanage -r resets Quick Look Server and all Quick Look client's generator cache.

2.  qlmanage -m gets all sort of information on Quick Look server including the list of detected generators.

3.  qlmanage -t displays the Quick Look generated thumbnails (if available) for the specified files.

4.  qlmanage -p displays the Quick Look generated previews for the specified files.

5.  qlmanage -h displays extensive help.

Oddly, per the answers to this stack overflow question, you will never know if Apple notices or addresses your bug. At best, I suppose you can try and narrow down the cause.

  • wow, never knew qlmanage could do all that stuff! I'll check it out right away! I've uploaded the image you asked too – FotisK Feb 7 '17 at 20:25
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    Again the previews & thumbnails generated by qlmanage command line appear just fine (until I decide to zoom in). With debug level 1 I was getting a warning that there may be other qlgenerators shadowing the default one so I ran qlmanage -g "/System/Library/QuickLook/Image.qlgenerator" -c "public.image" -p imagename.JPG -d 1 and nothing changed – FotisK Feb 7 '17 at 20:48
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    exporting the generated thumbnails into a file also reveals that the thumbnail is properly generated - it's a problem with the display of it! – FotisK Feb 7 '17 at 21:06

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