P: ICC Table Profiles clipped shadows under OSX

[Max_Ramuschi]

Hi, I've just found a really bad issue occurring in Lr 5 (but also in all other Lightroom versions) under Mac OSX 10.9 with a calibrated monitor: dark shadows (from a value of 20 to 0) are all clipped (pure black with no detail and no textures) while the histogram remains ok, indicating NO clipped shadows at all. This issue afflics also ACR.

Photoshop for now is the only software under MAC that reproduces dark shadows correctly: Library Module shows a bit darker and shifted shadows than Ps but acceptable, Develop Module is really bad showing brutally clipped shadows (but you work in the Develop Module right?!).

The same problem occurred also in OSX 10.8 but it was related only to LUT profiles, creating a Matrix based profile problems were solved.

Now the issue occurs with both Matrix and LUT profiles, v2 and v4. There's no apparent way to make Lr working right.

Under Windows no problems at all: Bridge, Photoshop, ACR, Lr (Library Module and Develop Module) show the same correct NOT clipped shadows.

I tested 8 different Mac running 10.9 with different GPU, different monitors, different profiling Softwares (Color Eyes Display Pro, Eizo Color Navigator, BasICC Color, i1 Profiler). Same results.
I tried to change the gamma value (2.2, sRGB, L*) problems remain. I tried to change ICC version (v2, v4) problems reamain. I tried to change profile type (LUT, MATRIX) problems remain.

How can a photographer work professionally on RAW images if shadows are bad reproduced?

Why Photoshop can reproduce shadows correctly while Lr isn't able to do that?

Why this happens only on a Mac enviroment?

Is Lr based on ColorSync (that can't handle profiles correctly) while Ps isn't (because it can handle and it has no problem)?

Please Adobe, FIX IT for all professional photographers, we can’t use Lr for serious works under Mac.

Max Ramuschi
Adobe Certified Expert

p.s.: Added a 100% Crop screenshots that shows the problem, some photos are even worse...

[MadManChan2000]

To be clear, the issue being experienced here in Lr is unrelated to the GPU.

The reason I asked some of you (offline) GPU-related questions for Ps is that the color values you will see in Ps can (often does) depend on whether you have GPU support turned on in Ps's Preferences panel.

(If you want to see what I mean, take Jao's test image and convert it to a color space that has a linear gamma, e.g., create a customized version of Adobe RGB, sRGB, or ProPhoto RGB with gamma of 1.0 -- you can use Ps's Color Settings panel to do this -- and then view that in Ps with the GPU option enabled vs with the GPU option disabled.)

[Max_Ramuschi]

We are aware of that kind of problem, but in my experience setting GPU to basic in performace tab, will solve every issue.

[Jao vdL]

Well it cannot solve the Lightroom issue. That is completely impossible. There is no GPU setting in Lightroom and Photoshop preferences have no effect on Lightroom.

[Max_Ramuschi]

no no, it's a completely different thing. Maybe Eric asked us if we were using GPU in Ps, because he wanted to be sure that we were comparing the same image in Lightroom and in a non GPU-issue-affected Photoshop .

[Jao vdL]

I am getting my signals crossed here. Didn't see who was asking questions and what the thread was in the email notifications. I thought you wanted me to try to change the setting in Photoshop and see if it fixed Lightroom. That didn't make any sense. Will try what Eric is asking.

[Max_Ramuschi]

Eric was saying another thing about PS. There's nothing we can do to solve Lr issue. We must wait.

[Jao vdL]

Don't really see a noticeable difference between GPU basic or GPU advanced in Photoshop using a linear ppRGB version of my little test image. I don't even see a difference when I turn of the GPU acceleration completely. They both look correct and hugely different from the affected Develop.

[MadManChan2000]

Jao, when you converted to Linear ProPhoto and switched GPU mode on/off, did you make sure to quit/restart Ps completely in between tests?

[Jao vdL]

Yes, I was thinking that might matter so I quit PS completely and restarted between. No difference that I could tell. Maybe in the very very dark patches (1,2, and 3 in sRGB 8-bit numbers), but those are very hard to make out to start with. Any effect is far smaller than what I see in Lightroom where every dark patch upto and including 15 is strongly affected when switching between Library and Develop with the same linear file. Library looks like Photoshop and looks like what the file looks like in Lightroom in both modules on Mountain Lion.

[MadManChan2000]

Interesting.  (Doesn't match my experience re: GPU.  I'll have to follow up on that later, and separately.  Sorry for the distraction ...)  In the meantime, I've identified the smaller issue regarding table-based display profiles in the Camera Raw plug-in (ACR) and this should be fixed in the final version of ACR 8.7.  This issue should have occurred on both Mac and Windows, by the way.

I'm still looking into the (much more noticeable) issue regarding Lr's Develop module, which happens on the Mac and for both gamma-based and table-based ICC display profiles, and hope to consult with the team's engineers in the next day or so to determine the root cause.  (I have a pretty good idea, but I'd rather know for sure rather than just guess ...)

I just wanted to let you know that this issue is being investigated, and to thank the folks here for all of the details, which have been very helpful.

[Jao vdL]

Let me know if I can help more with that. Glad that you are investigating these issues. Very much appreciated as it has bothered me for a long time now.

[Max_Ramuschi]

Jao, please try to create a LUT based or Table based Profile for your display and check if the library module is darker than PS.

[Max_Ramuschi]

Eric, you're right: the issue you identified is affecting ACR on Windows also, when using a table-based profile. I'm not a good observer...

[Jao vdL]

Massimiliano. I did the LUT based profile and indeed the dark patches in Photoshop are slightly darker in "Advanced" mode vs "Basic". Not much but still.

[Max_Ramuschi]

I noticed some magenta shift and bad transitions between contiguous tones... But it depends on the GPU and drivers. you can observe the issue on both mac and win. For me it's not a major issue because it's easily fixable.

[Kelly Castro]

An update: Eric has identified the source of the clipping issue and we are currently testing a solution. More info as it becomes available. Thanks for your patience.

[FeedbackCommunityMember]

Yay! The best news of the day! The future is smiling to me again - with LR! 🙂

[Max_Ramuschi]

Good news. Keep us informed!

[nesys75]

Very good news 🙂 awaiting for a fix. Thank you very much !!!

[Jao vdL]

Fantastic. Can't wait!

[Max_Ramuschi]

The really important thing (for me at least) is that Lightroom will become able to handle table-based profiles in every module. I personally don't use matrix based profiles at all, as they are not too precise.

[MadManChan2000]

FYI, Massimiliano, you may be confusing two different concepts: the color transform and the gamma encoding (1D functions). The color transform may be matrix-based, or table-based. The gamma encoding can be polynomial-based, or table-based.

Both ICC profiles that you sent me actually use matrices for the color transform, so these are both considered matrix-based profiles.

However, one of the profiles uses a polynomial gamma encoding, whereas the other profile uses a table for the gamma encoding.

So, the underlying issue here actually is not matrix-based vs table-based for the color transform itself, but rather polynomial-based vs table-based for the gamma encoding.

[Max_Ramuschi]

Ok understood, I call that profile table based or LUT based because Eizo Color Navigator calls it this way. The options you can choose in that software are 'LUT Based' or 'Gamma Curve', to be honest I've never looked into the profile itself. So the problem is actually about the gamma encoding right? It's a gamma issue with perfect matching colors indeed...

[FeedbackCommunityMember]

Great! I'm having this issue with a series of black on black images. Need a fix soon!

[kavemano]

I to have this issue. I don ́t occur when viewing TIFFs or JPS ́s only dark CR2 and DNG ́s.

It ́s very annoying.