# Awful Posterization / Color Profile Problem



## George Dibble (Nov 18, 2018)

About a  month and a half ago, my images began inexplicably displaying in Lightroom with severe posterization, in both the Library and Develop modules.  For reference, I edit on a laptop, but use an external Asus PA248Q for editing.  I have periodically calibrated the latter (using DisplayCAL) every six months or so.  Until this sudden change, I have not had any problems with its profiles interacting poorly with Lightroom.

I've tried re-calibrating, and I've checked to see if a basic sRGB profile works.  Neither of these options has shown any improvement.  Interestingly, Lightroom does not exhibit this behavior when I use it on my my laptop screen.  Neither does the posterization show up if I'm viewing jpg files in a run-of-the-mill viewer on my external monitor.

Does anyone have any recommendations?  I'm out of ideas altogether at this point.  I've attached an export of a raw, completely unedited photo, as well as a screenshot of the same image when viewed within Lightroom.

Thanks!


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## Zenon (Nov 18, 2018)

I have not heard of this one before and I hate to bring this one up before someone answers with a solution. It seems when odd things start to happen re-installing LR usually solves most issues.


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## Umberto Cocca (Nov 18, 2018)

Check the properties of the external screen, resolution and color depth. Check if you have latest driver for that screen. Try to change data cable, try same screen on other laptops 

Sent using Tapatalk


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## George Dibble (Nov 18, 2018)

Zenon said:


> I have not heard of this one before and I hate to bring this one up before someone answers with a solution. It seems when odd things start to happen re-installing LR usually solves most issues.



This is one thing I've not thought of.  Thanks!  I'm going to treat it as something of a last resort, but I may quickly get to this point.


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## George Dibble (Nov 18, 2018)

Umberto Cocca said:


> Check the properties of the external screen, resolution and color depth. Check if you have latest driver for that screen. Try to change data cable, try same screen on other laptops
> 
> Sent using Tapatalk



Thanks for the tips.  I've tried each of these.  None of those seem to be the problem.


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## Zenon (Nov 18, 2018)

George Dibble said:


> This is one thing I've not thought of.  Thanks!  I'm going to treat it as something of a last resort, but I may quickly get to this point.



No guarantee but you have nothing to lose.


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## Umberto Cocca (Nov 19, 2018)

George Dibble said:


> Thanks for the tips. I've tried each of these. None of those seem to be the problem.


Sorry to hear that... Sometimes we miss the simplest and most obvious.
Does any other photo viewer experience the same issue on that monitor? 

Sent using Tapatalk


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## clee01l (Nov 19, 2018)

What happens when you set Windows to use the factory sRGB color profile on the ASUS Monitor.  If you are still getting posterization with the factory  Color Profile, then I would suspect the monitor is failing.


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## Zenon (Nov 19, 2018)

The only thing that makes we wonder is this comment the OP made. _Neither does the posterization show up if I'm viewing jpg files in a run-of-the-mill viewer on my external monitor._


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## George Dibble (Nov 19, 2018)

Umberto Cocca said:


> Sorry to hear that... Sometimes we miss the simplest and most obvious.
> Does any other photo viewer experience the same issue on that monitor?
> 
> Sent using Tapatalk



No problem.  Although I've been calibrating my display for a few years now, this is the first time I've run into any problems.

When I open a jpg in the stock Windows photo viewer, it does not display the same issue on the external monitor.  This tells me the problem seems to be specifically with how either my monitor or the calibration profile is interacting with Lightroom.


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## George Dibble (Nov 19, 2018)

clee01l said:


> What happens when you set Windows to use the factory sRGB color profile on the ASUS Monitor.  If you are still getting posterization with the factory  Color Profile, then I would suspect the monitor is failing.



I still get posterization with a plain sRGB profile on the monitor, but only in Lightroom.  Viewing the identical exported jpg in the Windows photo viewer (for instance) does not show the same behavior, regardless of color profile.  I also checked how Photoshop does, and it seems to be fine.


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## LRList001 (Nov 19, 2018)

George Dibble said:


> I still get posterization with a plain sRGB profile on the monitor, but only in Lightroom.  Viewing the identical exported jpg in the Windows photo viewer (for instance) does not show the same behavior, regardless of color profile.  I also checked how Photoshop does, and it seems to be fine.



It sounds like LR has a serious difference of opinion with the OS as to the resolution of the monitor.
What technology are you using to connect to the monitor (VGA/HDMI/DP/etc)?
Have you exported the working jpeg and imported it back into LR, maybe in a new catalogue?
If you drop the resolution of the exported jpeg (or a tiff) down somewhat, and re-import, does LR then get it right (ie the same as outside LR)?
Have you tried setting a different resolution on the external monitor (then set it back again)?


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## George Dibble (Nov 19, 2018)

LRList001 said:


> It sounds like LR has a serious difference of opinion with the OS as to the resolution of the monitor.
> What technology are you using to connect to the monitor (VGA/HDMI/DP/etc)?
> Have you exported the working jpeg and imported it back into LR, maybe in a new catalogue?
> If you drop the resolution of the exported jpeg (or a tiff) down somewhat, and re-import, does LR then get it right (ie the same as outside LR)?
> Have you tried setting a different resolution on the external monitor (then set it back again)?



I'm using HDMI as my connection method.  Although the monitor has a wider variety of options, that's the only one that my computer will employ.

Per your questions, I've tried different resolutions on the monitor (followed by resetting to its recommended setting (1920 x 1200), as well as importing both the unaltered and altered resolution versions.  No change.

I don't know if this is particularly relevant to my problem, but the posterization is most pronounced in the low-mid-tones of an image.  Highlights don't seem as affected.


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## LRList001 (Nov 20, 2018)

George Dibble said:


> I'm using HDMI as my connection method.  Although the monitor has a wider variety of options, that's the only one that my computer will employ.
> 
> Per your questions, I've tried different resolutions on the monitor (followed by resetting to its recommended setting (1920 x 1200), as well as importing both the unaltered and altered resolution versions.  No change.
> 
> I don't know if this is particularly relevant to my problem, but the posterization is most pronounced in the low-mid-tones of an image.  Highlights don't seem as affected.



Can you borrow another HDMI monitor?


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## LouieSherwin (Nov 22, 2018)

Hi George,

I think that this is more likely that  something is out with your color management for that monitor. Such as  your monitor profile for your Asus not handling the deep saturated blues in the sky. Or that you do not have the profile correctly installed. I would double check the Window color settings and the monitor hardware settings to make sure that you are using the current monitor profile and that you haven't accidentally changed the color settings in the monitor. 

Also have you recently upgraded DisplayCAL? What colorimeter are you using and how old is it? These devices to age and need to eventually be replaced.

-louie


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## George Dibble (Nov 25, 2018)

LRList001 said:


> Can you borrow another HDMI monitor?


I connected my laptop to my television (Sony Bravia, for what it's worth) and was not able to replicate the problem.  This leads me to think that there's something wrong specifically with my monitor, although I still can't figure out for the life of me why it would only manifest itself within Lightroom.


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## George Dibble (Nov 25, 2018)

LouieSherwin said:


> Hi George,
> 
> I think that this is more likely that  something is out with your color management for that monitor. Such as  your monitor profile for your Asus not handling the deep saturated blues in the sky. Or that you do not have the profile correctly installed. I would double check the Window color settings and the monitor hardware settings to make sure that you are using the current monitor profile and that you haven't accidentally changed the color settings in the monitor.
> 
> ...



Louie,

Those are all thoughts that have run through my head as well.  I've checked the profile, and verified that the problem persists even if I use a different profile (such as the standard sRGB profile).  Additionally, the problem doesn't show itself if I view the same image as an exported jpg in a different program.

I'm running the most recent DisplayCAL version, although before I started this troubleshooting process about a month ago, I was running a previous version.  I'm using a Spyder 5 Pro, which is about 3.5 or 4 years old.

Based on all of the trial and error I've tried, I'm starting to think my monitor is the problem, but I can't figure out why it would only be evident within Lightroom, and not when viewing the same images in a different program.


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## LouieSherwin (Nov 27, 2018)

George,

Hi George,

I still don't think that this is a problem with the monitor. The banding in dark blues is consistent with a profile that is not able to smoothly map the image colors to the output device.

My description below is somewhat detailed and may cover much of what you already know but I include it for clarity and to make sure anyone else that comes across this later can get see all the pertinent details. 

Lightroom's internal workspace is ProPhoto RGB. This has an extremely large range of color (gamut) that includes the entire range of human vision plus some colors outside our vision. The gamut of the working spaces Adobe RGB ,sRGB and all output devices (monitors and printers) are quite limited by comparison. This means it quite easy to make edits especially to a raw image  in Lightroom especially to saturated colors that pushes the image gamut outside these others. I am pretty sure that this is what is happening with your image. There are colors contained in the image that you are not able to see with the limited gamut of your monitor.

The banding you are seeing in the saturated blues is happening when colors contained in the image file are being compressed to fit in the gamut of the monitor. You might think that the solution would be to convert the image to a smaller color space, sRGB for example. That would eliminate the banding as you have seen with JPEG versions of the image. However, if you remove that color information permanently you can never get it back. Most modern inkjet printers now have color gamuts larger than sRGB even approaching Adobe RGB and most medium to high end monitors have  a gamut close to Adobe RGB. 

The solution is already built in to you computer. It is part of the operating system called the Color Management System (CMS). It is the job of the CMS to translate colors between working spaces and devices, input and output. One of the main problems it has to handle is how to map the out of gamut colors coming from a wide gamut to a smaller gamut. When working correctly it will produce a visually pleasing representation. 

In the Lightroom Develop module the image data is being processed within the very large ProPhoto RGB working space. As you make edits in Lightroom the image is re-rendered still in ProPhoto RGB. At the end of each rendering this image data is passed to the display driver to be displayed on the monitor. This is where the device profile is key. The display driver uses the CMS which in turn uses the device profile to translate the ProPhoto RGB numbers into corresponding RGB numbers that when sent to the monitor will be perceptually accurate. 

The above is basically the same for images viewed in the Loupe view except all previews are rendered from the latest develop settings as JPG images and converted to Adobe RGB by the CMS. Adobe RGB is quite a bit larger than your monitor gamut. So when you view the images on your monitor in Loupe view the driver and CMS still have to map any out of gamut colors into the monitor gamut.

It is in this step where the banding is occurring. It could be any part of the CMS but it is most likely due to a faulty or poorly constructed device profile for the monitor.  The device profile* being used* by the CMS simply doesn't have sufficient information for how to map the out of gamut saturated blues to the gamut of the monitor and it stumbles and ends up with the ugly bands. I emphasize "*being used*" here because it is possible that the CMS is somehow using the wrong profile a bug or obscure setting etc..

The reason you are not seeing banding with the jpg version of this image is probably due to the fact that as you exported it to JPEG it was converted to sRGB which is the default for JPEG. Therefore the out of gamut colors are already adjusted to be within the range that can be displayed by your monitor.  I predict that if you export this image as a TIFF in ProPhoto RGB and then display this exported image with a "*color managed application*" that you will still see the banding. There are a lot of apps out there especially in Windows that are not color managed and the results of those will not be an accurate test.

Keep in mind that because your monitor only has a gamut that is close to the gamut of sRGB you will never be able to see these deep saturated colors that are present the image and are probably present in the original raw capture. This is a physical limitation of the monitor.  So even if everything is working correctly all you will be able to view is an approximation of what is in a highly saturated image. 

In a different sense  your monitor is part of the problem due to it's restricted gamut. sRGB is a through back to the days of CRT monitors. Todays modern digital sensors are all capable of capturing a gamut larger than Adobe RGB. Trying to edit raw images with such a limited gamut is going to be difficult. You simply won't be able to see changes in saturated colors. 

I would try making a new monitor profile using the software that came with your Spyder 5. Also it could be that your Spyder 5 is not working correctly . These devices do degrade over time and it simply may be making incorrect measurements that are causing a bad profile to be generated. If you know anyone nearby, perhaps a photo club, who has another colorimeter it could be useful to try that.

Regardless of whether or you get a new monitor you should try resolve the banding issue. Because if you don't then you are likely to perpetuate it with the new monitor. 

-louie


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## Victoria Bampton (Nov 28, 2018)

LouieSherwin said:


> I would try making a new monitor profile using the software that came with your Spyder 5. Also it could be that your Spyder 5 is not working correctly . These devices do degrade over time and it simply may be making incorrect measurements that are causing a bad profile to be generated. If you know anyone nearby, perhaps a photo club, who has another colorimeter it could be useful to try that.


That's my suspicion too. I had one that created odd banding when it still passed the manufacturer's verification.


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## clee01l (Nov 28, 2018)

Victoria Bampton said:


> That's my suspicion too. I had one that created odd banding when it still passed the manufacturer's verification.


I recommended using sRGB to check against the computed icc Profile and this was the response: 


George Dibble said:


> I still get posterization with a plain sRGB profile on the monitor, but only in Lightroom.  Viewing the identical exported jpg in the Windows photo viewer (for instance) does not show the same behavior, regardless of color profile.  I also checked how Photoshop does, and it seems to be fine.


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## LouieSherwin (Nov 29, 2018)

Cletus,

I understand  your suggestion above but I am not sure what it has revealed. Posterization or banding (the same thing) in digital output is an indication that the CMS having difficulty mapping colors from a wider gamut source to a smaller gamut destination. I cannot think of any way that a failure of the monitor would produce such a specific type of banded output. 

I believe but have not yet confirmed from George that the test version of image use outside of Lightroom is JPEG with sRGB because that is the default export settings. That would explain why he doesn't  see the banding outside of lightroom as Lightroom has done a good job mapping the out of gamut tones into sRGB. 

This is also why I  requested that he make some additional test images exported with wider gamut color spaces.  Specifically I want to see what happens when viewing the image  that is exported with the ProPhoto RGB color space. That will give an apples to apples comparison of how the CMS is working outside of Lightroom.  

Is Windows Photo Viewer color managed? If not is there another color managed tool?  Unfortunately I am simply not knowledgable of the Windows color eco-system to offer specific knowledge.

Regarding your suggestion of replacing the monitor profile with sRGB. The fact that it didn't seem to make any difference indicates to me one of several possibilities, incorrect settings in the Windows color setup, a bug the Windows CMS or even some incorrect settings in the monitor itself. 

-louie


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## LouieSherwin (Dec 2, 2018)

George Dibble said:


> I'm using HDMI as my connection method. Although the monitor has a wider variety of options, that's the only one that my computer will employ.



Hi George,

I came across this post in the Luminous Landscape forum and it may be relevant to your problem. HDMI vs DisplayPort cable? In the first reply there is a reference to HDMI output being restricted. This could be what is causing the banding to be seen in the out of gamut regions of your image.  

If this is the case then you will need to either find a way to change the output of the HDMI port on your computer or perhaps even get a new computer with more advanced external display interface.

-louie


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