Calibration Issues (esp. Black Point) with MacBook Pro Retina 13" Display

[jnewell]

Searched here and elsewhere - not seeing any explicit discussion of this issue, and would welcome feedback.

I'm working with a 13" MacBook Pro with retina display.  It would be used occasionally for editing photos in Lightroom while traveling.  Although I don't expect to be able to do critical editing with this laptop, I want to know how close it can get.  My concern is that with default settings the black levels shown at lagom.nl (link) are almost completely lost - basically all that shows up is the bottom row.

With my calibrated Windows machines (laptops and desktops), I have no trouble distinguishing all of the rows.

I spent a couple of hours today with an i1Display Pro and while the colors are somewhat better (they weren't bad to start with), the black levels are still telescoped. 

To try to determine whether there was something wrong with this display, I took it to an Apple store and compared it to a large number of other displays, and got the same results (uncalibrated) with all of the displays (other than a few MBA 11" machines - go figure).  Obviously there's noting particularly wrong with this particular notebook.

Am I missing something/doing something wrong?

[digitaldog]

My concern is that with default settings the black levels shown at lagom.nl (link) are almost completely lost - basically all that shows up is the bottom row.

I'd kind of ignore all that, doesn't seem to be a very good way to gauge what YOUR display is doing considering it's being viewed on the web etc.
Try this instead: http://www.ppmag.com/reviews/200412_rodneycm.pdf
You want to assign your display profile to a black document to test how well you've calibrated to black. That's not happening in the above test.

[jnewell]

Thanks and a very fair point.  For what it's worth, I downloaded the discrete jpg version of that image and opened it in Lightroom, where it looks essentially the same. 

Thanks also for your pdf - wondering if I can replicate the process with PSE?  I do most of my editing in Lightroom.

The thing that's bugging me is that on the Windows machines I seem to be getting a much better range of black values.   

[D Fosse]

doesn't seem to be a very good way to gauge what YOUR display is doing considering it's being viewed on the web etc.

Why not? It seems like a very healthy and useful test image to me. If you view it in Firefox/mode 1 you get a fully color managed sRGB version, and you should be able to separate all the way down to 1. You can also open it in Photoshop and assign sRGB, but the result is the same. Lightroom should also assign sRGB.

The numbers correspond to the sRGB values: 1,1,1 - 2,2,2 - 3,3,3 and so on.

That said, there is a bug in the OpenGL rendering in Photoshop where the lowest values, below 5 or so in sRGB, are crushed into black (depending on display profile type). The crush lifts when you set OpenGL to the "basic" setting, where the color management logic is shifted back from the GPU to the CPU. It also causes irregular and colored banding in ProPhoto (this was discussed in another thread recently).

Back to the lagom test image: in a dim room I can easily separate all the squares down to 1 on an Eizo CG246. But even with a laptop you should be able to see down to 5 or 6 or so. If separation begins all the way up at 20, something's clearly wrong.

[digitaldog]

Why not?

Because you are not assigning the display profile to the document to evaluate the calibration of black.

[D Fosse]

Yes, but - excuse me if I'm being dense - no matter what the calibrated black point target, the values from 1 and up should still be remapped through the display profile, relative to that black point?

Surely, if there's no separation below 20 something has to be wrong, either in the profile or in the conversion (or the display itself)?

[digitaldog]

To evaluate the actual calibration of black, you have to disable Display Using Monitor Compensation in ICC aware app's. To do that, you assign the display profile to the document, something that web page can't possibly do in ICC aware web browsers (and outside, it's useless).
In a prefect black calibration, you'd visually see a tiny difference between RGB zero and RGB 1. And on the old Sony Artisan, you could hence this test designed by Karl Lang to evaluate black calibration.

[D Fosse]

Yes, I know that assigning the display profile disables display color management, leaving you with the native response of the display in its calibrated state (or the actual calibration as you say). Yes, I get that.

I'm really not trying to be argumentative, but I just can't wrap my head around how shadow separation that starts at around sRGB 20, 20, 20 is something you can just "ignore". In my book that's a red flag with a sign around its neck: "Hold on. We have a problem here". And I'd point my finger at the display profile as the likely problem.

Even a cheap TN display will separate down to sRGB 5 or 6, give or take a little for laptops. But Macbook displays are certainly not the worst of laptop displays.

Feel free to tell me to shut up anyone, in case there's something simple I'm missing. But I just don't get this.

[digitaldog]

Yes, I know that assigning the display profile disables display color management, leaving you with the native response of the display in its calibrated state (or the actual calibration as you say).

It really doesn't disable color management. It does disable the Display Using Monitor Compensation so you can examine the actual behavior of the dispaly calibration, in this respect how black is being calibrated. It's now a null conversion but color management is still in effect (the display profile is still used to produce the image on-screen).

[D Fosse]

Yes, it will; assigning the display profile (instead of the color space the file was created in) does change the appearance. So yes, it is used to produce the image on-screen. OK.

I still insist the OP has a problem with his profile/conversion though.

[jnewell]

Yes, it will; assigning the display profile (instead of the color space the file was created in) does change the appearance. So yes, it is used to produce the image on-screen. OK.

I still insist the OP has a problem with his profile/conversion though.

Can you elaborate?  I think I've got this thing profiled as well as i1Publish is going to let me, unless I've missed some key setting in the setup process. 

[D Fosse]

I'm sure you have. What I've been getting at all along is that black clipping starting at sRGB 20 or so is indicative of a problem somewhere in the document profile > display profile pipeline. There's no way that's normal.

There was a thread in the Adobe Lightroom forum a while ago describing something very similar to this ("Lightroom 5 ICC profiles clipped shadows under OSX"). It took me a while to find it but I finally did:

https://forums.adobe.com/message/6027420

[jnewell]

I'm sure you have. What I've been getting at all along is that black clipping starting at sRGB 20 or so is indicative of a problem somewhere in the document profile > display profile pipeline. There's no way that's normal.

There was a thread in the Adobe Lightroom forum a while ago describing something very similar to this ("Lightroom 5 ICC profiles clipped shadows under OSX"). It took me a while to find it but I finally did:

https://forums.adobe.com/message/6027420

That's why I asked.   Thanks for the link - I'll read it today.

[Tim Lookingbill]

Maybe this will help make it more understandable as to why Andrew insists on Assigning the display profile in order to assess true black point capabilities of a display's native state.

The first graph of the curves is the 2.2 gamma curve of my LG 27" LED display to correct for any nonlinear behavior as measured by a Minolta color analyzer at the factory and represents the native state of my display which happens to be close to 2.2 gamma. Note the section cirve that represents black and shadows which can get pretty tight and go out of wack just with a slight brightness, contrast and white balance tweak.

The second curve is from my custom Colormonki Display profile containing the standard 2.2 gamma as a reference for a color managed apps to control previews. The third is a vcgt tag that is included on all Mac OS custom profiles and permanently resides on the video card when the custom profile is chosen in Display Preferences as the system profile but must be turned off by assigning the custom display profile in color managed apps in order to see exactly the true state of your uncorrected display.

Windows systems use a separate LUT/vcgt loader on startup so that can get problematic on knowing when this gets turned off/on. Also vcgt corrections may not be as clean like mine and have lots of tweaks applied to each RGB curve which really needs to be turned off to see the native state.

[D Fosse]

Yes, I understand that. I just don't see why it's relevant here.

I'm well familiar with the shadow dip in an LCDs native response (it's easily observed in non-managed browsers). Some of this is corrected in calibration, the rest described in the profile and compensated in the conversion. This is why we have a color managed display pipeline, to compensate for all these imperfections.

Anyway, I re-read the thread I linked to, and the whole thing ended up with bug reports to Apple. There was clearly a problem with how some display profiles were handled in OSX 10.9. What happened to it after that I don't know.

[Tim Lookingbill]

Yes, I understand that. I just don't see why it's relevant here.

My comments weren't directed at you.

They were directed toward the OP's wanting to use Lagom website in a browser to test black point calibration and I was backing up Andrew's claim it's best to use the black level test in native monitor space in Photoshop which will clear the video card of any manipulations to correct for the display's physical native non-linear behavior embedded in the display profile.

Your issue with Lightroom's 20RGB black level is something I have no idea how to correct.

[jnewell]

My comments weren't directed at you.

They were directed toward the OP's wanting to use Lagom website in a browser to test black point calibration and I was backing up Andrew's claim it's best to use the black level test in native monitor space in Photoshop which will clear the video card of any manipulations to correct for the display's physical native non-linear behavior embedded in the display profile.

Your issue with Lightroom's 20RGB black level is something I have no idea how to correct.

In my second post in this thread I clarified that I had indeed downloaded the actual image and imported it into Lightroom, with no difference in results.

[Tim Lookingbill]

In my second post in this thread I clarified that I had indeed downloaded the actual image and imported it into Lightroom, with no difference in results.

And you assigned your custom display profile and resaved the actual image you downloaded so you can import it into Lightroom, right? Lightroom is color managed just like Photoshop.

If this didn't fix your problem with black levels on your laptop then there's something buggy going on with either LR and/or the Mac OS. Can't help you with that.

One other suggestion would be to view that downloaded image at 100% view in LR.

[rubencarmona]

Hi jnewell

How did you exactly calibrate your monitor?

I use a MBP 13" Retina myself which I calbirated with my Spyder4Elite.
I turned on the Iterative Gray Balance here (only possible with Elite) and the ambient light compensation.

Please be aware that your ambient light is also a big point when having black points as reference.

Once calibrated like this, I can distinguish these black points on the homepage you mentioned from point 8 to the end.

To help out, please describe how did you exactly calibrate your screen.

[jnewell]

And you assigned your custom display profile and resaved the actual image you downloaded so you can import it into Lightroom, right? Lightroom is color managed just like Photoshop.

If this didn't fix your problem with black levels on your laptop then there's something buggy going on with either LR and/or the Mac OS. Can't help you with that.

One other suggestion would be to view that downloaded image at 100% view in LR.

Yes to both.  Based on a lot of reading, it does appear that there is an unresolved problem in OS X 10.9.

I have been tweaking the display profiling variables and have gotten the rMBP so that it's close to the PCs. 

Amusingly (maybe), running the retina display as "scaled | more space" that image is still pretty small at 1:1.  Kicking it up to 2:1 fills the workspace better.

I'm pretty happy with how this has worked out.  I'm not trying to do critical/final processing on this laptop.  If I were, I think an external display would be mandatory, but that's what my desktop PC is for.