Colour Management Headache

Particularly now that I've turned on color management on Firefox 3.

The docs say to set 6500k and 2.2 gamma, but the 6500k I suspect is making it too red shifted when color managed.

Definitely need to read up on this...

Going to re-profile my monitor tonight to see if that helps...

--
Matt Fahrner
http://www.boinkphoto.com

I think it's a bit more important than that. For instance if you're going to publish to the web and Lightroom is showing the flower as "purple" and when it ends up on the web as "pink" (which frankly might happening to me), then it can cause some trouble.

That's not to say your basic point about what is ultimately "important" isn't correct, but having the color management right can be fairly critical...

--
Matt Fahrner
http://www.boinkphoto.com

Well Scathew, there is truth in it. The numbers never lie. For example you know that L50 A10 B0 is a lightish magenta, or that L25 A50 B-50 is a dark purply colour. So, regardless of what you see with your eyes if the LAB numbers are correct, then you know that the colour is correct. Now your monitor, or anyone elses monitor for that matter might make a hash of it, but the underlying value is correct.

Having a correctly calibrated system however aids expedience and operator enjoyment which IMO is very important!

scathew said:

The docs say to set 6500k and 2.2 gamma, but the 6500k I suspect is
making it too red shifted when color managed.

Click to expand...

I find it hard to accept calibrating at anything other than 6500K. But as to whether the docs say you should depends on which docs you read. If it is a CRT monitor, then calibrating to 6500K is almost universally accepted. But if it is an LCD, the case is less strong. For example, see what Andrew Rodney, another great guru of colour management, says in this thread:
http://www.openphotographyforums.com/forums/showthread.php?t=3302

He says that you should not attempt to calibrate an LCD, even a high end one, to 6500K but should accept and profile it at its native white point.

Being somewhat uncomfortable with that idea, and the resulting appearance, I "calibrated" my laptop to 6500K. But images look rather pink (or "red shifted", as you say) on it compared to my CRT, which is also calibrated to 6500K.

I would hate to have to judge colours on an LCD monitor, even one of those ridiculously expensive Lacie or Eizo jobs! I love my Viewsonic CRT so much that I recently bought another to keep as a spare so as to delay the time when I might have to put up with an LCD monitor. I'd willingly have bought two if I weren't so short of space.

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******************************************************
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Ok, so I have a Spyder2 Plus (which is just a Spyder2 with some printer profiling software).

I put the Spyder 2 on my laptop, run Spyder2PRO 2.3.5, go through the calibration and everything looks great (even using 6500k and 2.2 gamma, though perhaps I should use native gamma). After definitely looks much better than before and of course the whole screen shifts when going to before and after. I save the profile and I'm done (I think).

Now it says it set the default Windows profile to the one I created, but it doesn't because there is a known bug. No problem, I manually do so through the control panel and find "Color Management" and set it as the default profile. Just for good measure I reboot.

So, laptop starts up happily, runs the "ProfileChooser" automatically and again, big shift as it loads the profile up. Again things look good (visually and otherwise).

Ok, so now I go to use Firefox 3 with color management on to look at something on the web I created a long time ago, say this:



And the skies, which using an unmanaged browser look blue and correct to my eye, now look PURPLE!

Funny thing is if I download the image above and load it into the also color managed Photoshop, it also has purple skies (for instance the one with the mountains and yellow fields below is wicked purple)(yes, I'm from New England).

Do you guys see purple skies???

If I set Photoshop's working space to the monitor profile I created (instead of sRGB) then it goes back to the blue I expect, but from what I understand that's essentially turning color management off.

It kind of appears to me that I'm double correcting or something (the monitor is corrected via ProfileChooser, and then Photoshop/Firefox are also trying to correct, thus yielding purple).

What are you supposed to do here?

Any help would be appreciated.

--
Matt Fahrner
http://www.boinkphoto.com

So, you run the calibration program with a Spyder (or equivalent) aiming for 6500k and 2.2 gamma (6500k and 2.2 gamma from what I read being exactly what sRGB is defined around).

So it samples all the colors and generates a color profile. It then runs something that loads the LUT of the graphics card. Now, I assume when it loads the LUT all the colors output from the card now shift to compensate so that anything you display, regardless of application, should be manipulated so the colors look exactly as intended for sRGB assuming they are saved as sRGB.

That is, lets say you have a JPEG that was scanned on an accurate scanner that was outputting in the sRGB space. If you double click on on the JPEG and just get the default, unmanaged "Windows Picture and Fax Viewer" it will display this sRGB (which I assume "Windows Picture and Fax Viewer" is keyed for sRGB right since it's the "default"?) and then because the graphics card has the LUTs loaded, it should display, even with this unmanaged application, the colors of that scanned image correctly for sRGB? A red on the print should match the same exact red (or as close as possible) on the screen?

However, when you open this same JPEG in Photoshop, which is managed, and set to the sRGB color space (mine is), it does yet more manipulation (translation) and the colors shift? I don't get why (but it is happening).

Once the LUTs are loaded, based on the sRGB color corrections, shouldn't everything displayed, even those in unmanaged applications, be being compensated by the graphics card injected LUTs? Shouldn't even your desktop background, which I assume would be usually saved off as sRGB, look the same outside Photoshop as in? Yet when I load mine in (it's a picture I took and is in sRGB I believe), it shifts when going to Photoshop (or Lightroom too).

I guess if the LUTs weren't being loaded I would understand why Photoshop would compensate based on the color profile to make it look correct on the monitor, but if you have a program pre-loading the LUTs, shouldn't essentially all the work be done already? Shouldn't the graphics card have all the compensation needed already in it and have no need for Photoshop or any other color managed app to do even more compensation?

What am I missing?

Sorry and thanks!
--
Matt Fahrner
http://www.boinkphoto.com

actually, it sounds like you first edited these pics on an uncalibrated monitor, thought the color looked fine and now after calibration you see a purple shift. Its probably been there all along you just never saw it on your previously uncalibrated monitor. One of my mantras here and elsewhere is, "you can't edit false color". That may have been what you inadvertantly did before.

The only way to check it out is to print an image or have it printed. If your system is calibrated correctly, the print should pretty much match what you see in CS.
--
BigPixel / Hawaii

It's quite possible, and was a thought I had. However, it doesn't quite explain why if I have an RAW image in Lightroom today and export it as sRGB I get a major shift viewing it in "Windows Picture and Fax Viewer" (or Picasa), whereas if I load it into Photoshop it matches Lightroom perfectly.

There's definitely something funky here.

Incidentally I'm not sure it's in all color ranges, but may be specifically in the blue-purple.

Thanks for the response!

--
Matt Fahrner
http://www.boinkphoto.com

Its a Windows thing. I see a slight difference too between the windows/fax viewer and Photoshop. Just get used to it. The critical thing is that you are now calibrated and so every pic you edit from now on should look as you intended online and in print.
--
BigPixel / Hawaii

Windows Pic/Fax viewer is non colour managed (NCM), photoshop is.

When you look at something in a NCM application, you are at the mercy of your monitor manufacturers interpretation of the RGB values your file represents.

EG , the shade of blue you picked out for your sky is only showing up as blue to you because the manufacturer when they designed the screen thought "Yes, that value of 0,0,255 should look like this!"

When you calibrate your monitor what's happening is the device is comparing youe monitors interpretation of 0,0,255 with the actual laboratory tested value of 0,0,255. That's why you stick the sensor to your screen, to get actual physical feedback.

So now, you have a wee file (The icc profile) that basically adjusts colour values so that when your monitor displays them, they come out OK. Example...

If your monitor by default (In NCM apps) displays purple as pure blue, the profile will adjust the colourvalue of purple, as it makes the way to the screen, into a value that your screen wlill actually SHOW as purple, rather than letting your screen manufacturer interpret it as blue.

So, if you have your profile created and set as default, and you load photoshop into an sRGB working space and load up an sRGB image, because the application is colour managed (CM) photoshop is using the ICC profile to adjust the colours you see on screen as closely as possible to their true values. This means that now the purple that your monitor manufacturer thought was blue is finally, pun intended, showing its true colours. (Which you could check without any calibration at all by looking at the A channel in LAB mode...)

The benefit of all this, is because I have a calibrated system, if you work on the picture and save it with an attached colour profile, when I open it on my syste, it should be consistant. Without the profiling, the colour numbers in your file would display on my screen according to MY manufacturers interpretations, so your purple sky (Which was blue to you) might look cyan to me!

When it comes to the internet, now is the time to start uploading sRGB tagged jpgs. The reason being is that anyone without a calibrated system is a complete crapshoot anyway, you have no way of knowing or controlling what the heck they're going to see. Some of the monitors and screens I've seen in my time doing on site PC repairs have made me weep...

The upside is that anyone who cares enough about imaging to have a calibrated screen and CM sensitive browser will see things as you intended them to see them!

scathew wrote

scathew said:

That is, lets say you have a JPEG that was scanned on an accurate
scanner that was outputting in the sRGB space. If you double click on
on the JPEG and just get the default, unmanaged "Windows Picture and
Fax Viewer" it will display this sRGB (which I assume "Windows
Picture and Fax Viewer" is keyed for sRGB right since it's the
"default"?)

Click to expand...

First, sRGB is not the “default” for Windows. Windows has no default. Windows Picture and Fax Viewer does not “assume” sRGB and nor does any other unmanaged application. Unmanaged applications are not profile aware and they do not apply or assume any profile at all. Moreover, in a colour managed application, such as Photoshop, converting to Monitor working space is not the same as turning colour management off. It is important to distinguish between calibration (LUT) and profile (display profile held in the monitor profile).

When you use a Spyder, it first measures what the uncalibrated monitor does with colours. It then creates a LUT to attempt to alter those colours to be as close to target as possible, namely gamma 2.2 at 6500K, which is close to but not identical to sRGB.

It then loads the resulting LUT into the graphics card. The monitor should thus be calibrated close to gamma 2.2 6500K. It then measures what the calibrated monitor in fact displays. The result is the monitor display profile. The display profile represents what the monitor displays after calibration, not before.

Let’s take your hypothetical nice scanned jpeg with an embedded sRGB profile. If you open it in a non-managed app, the pixel values get fed to the graphics card, to which the LUT has been applied. The LUT is applied by the LUT loader, not by Windows.

The embedded sRGB jpeg profile is neither seen nor used and the output display profile is not used either. The colours displayed are whatever the LUT calibrated monitor happens to show.

If you open the jpeg in Photoshop (PS), with working space set to monitor profile, PS converts the pixel values from those of the embedded sRGB to those required by a device whose calibrated LUT applied output is defined by your monitor display profile. It does this by assigning the embedded profile and then applying the inverse of the monitor display profile. (If you save the jpeg and embed the profile at this point, PS will embed the monitor display profile rather than sRGB because the pixel values have been converted to monitor space). In order that PS can display the image on your screen while you are doing this, it applies the inverse of the display profile (again) to the values held in working space and throws the result at the graphics card (which applies the LUT to everything it receives).

In fact, the working space is irrelevant to what PS displays provided the image has an embedded profile and you have set PS to convert images to working space. If you set working space to adobeRGB, for example, PS would convert the input jpeg to adobeRGB. Then, to display the image to you, it applies the inverse of the working space (adobeRGB) followed by the inverse of the monitor display profile and throws the result at the graphics card. Saving the file, however, would result in embedding adobeRGB. The working space should affect the display only if you choose to discard the embedded profile when you open the image.

The upshot is this. If you display an image in PS, the LUT calibration is applied (as it always is, regardless of whether the application is colour managed or not) PS applies the image embedded profile and then applies the inverse of the display profile of the LUT calibrated monitor. If that latter profile is accurate, the result is a display that respects the image embedded profile (which is only sRGB if that is what was embedded). But note that nothing actually applies the display profile.

If you display in an unmanaged application, the LUT calibration is applied as always, the embedded profile is ignored and the inverse of the monitor display profile is not applied. The monitor display profile is not applied either (and never is, regardless of whether the application is colour managed or not).

LUT is always applied. Display profile is never applied. Inverse of display profile is applied prior to display by a colour managed application. Embedded image profiles are applied only by colour managed applications. So sRGB is applied only if embedded and viewed in a colour managed application.

scathew said:

I guess if the LUTs weren't being loaded I would understand why
Photoshop would compensate based on the color profile to make it look
correct on the monitor, but if you have a program pre-loading the
LUTs, shouldn't essentially all the work be done already? Shouldn't
the graphics card have all the compensation needed already in it and
have no need for Photoshop or any other color managed app to do even
more compensation?

Click to expand...

Should now be clear, I hope! The colour profile is the profile after LUT has been applied. It allows the (hopefully small) compensation that is needed for a colour managed application to correct for how the LUT calibrated display actually behaves, as defined by its display profile. LUT calibration is not precise, especially on LCD monitors. Display profiles should be more accurate, depending on how accurately the colorimeter (eg Spyder) measures.

Finally and not a major problem - but sRGB is not based on gamma 2.2 or 6500K. It is based on a power law curve that approximates to gamma 2.2 for most of its range except for the lowest brightnesses, where it is different. And the colour temp is for a D65 standard, which is similar to 6500K.

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To follow up on Denny's very good explanation:

As I already explained in my previous posts, calibrating is one thing, profiling is another. One cannot profile without hardware tool. Ditto.

So what is calibration?

Calibration makes sure all three channels R, G and B follow the gamma law, where gamma can be 1.8, 2.2 or arbitrary.

Second thing calibration makes, is it sets the white point to the desired value and black level to the minimum possible.

The above steps ensure, Gray is Gray in all of its range.

And that's all it can do. It doesn't take into consideration the black level, the white level and the Lab values of the R, G, B primaries (phosphors or filters), which by the way shift over time.
Remember, RGB is a device dependent system, CIE Lab is not.

This is where profiling comes to play. It helps PS or Firefox or any other CM application correct for the display's deficiencies.

In essence, almost all LCD users will notice that the picture will become slightly duller, and that's because the black levels of LCD are bad. What is PS doing it's levelling up the dark tones, so that the entire range of the grayscale is visible.

Just how many of you can see levels 5-8 in a non colour managed browser?
http://www.drycreekphoto.com/Learn/Calibration/monitor_black.htm
Now, try that with a colour managed browser. See the difference?

Since the eye records relations of values, this is not a problem once you get over the fact that in PS the pictures won't look as contrasty as your monitor can deliver.
Just get over this or buy a good CRT or esoteric LCD.

--Davor

scathew said:

Do you guys see purple skies???

Click to expand...

Yes!

scathew said:

If I set Photoshop's working space to the monitor profile I created
(instead of sRGB) then it goes back to the blue I expect, but from
what I understand that's essentially turning color management off.

Click to expand...

See my long reply elsewhere in this thread. It is not the same as turning colour management off. It only seems to be so with the image you posted because because it (is a gif and) does not contain an embedded profile. If there is no embedded profile, PS interprets the pixel values as if they are designed for your working space. It does not do a conversion because, without an emebdded profile, it has no way of knowing what you are converting from.

But if the image has an embedded profile, PS will convert it to the working space if you have set up the colour settings to do so. The embedded profile will then be respected.

Also, whatever the working space, PS still makes a correction for your monitor profile when you display the image. An unmanaged application makes no such correction.

Try the experiment again but first embed a profile in the image. For example, set working space to sRGB and then open your gif. Choose Image> Mode and choose RGB colour. Then save the image (as a copy) as a jpeg, which will embed the sRGB profile.

Now set your working space to something extreme, like ProPhotoRGB. Open your original gif and the jpeg alongside it, together in Photoshop. The gif will show the extreme colours of ProPhotoRGB but the jpeg will show the more muted colours of sRGB.

Now set your working space to monitor space, close the images and reopen them. The gif will display in the colours of your monitor space but the jpeg will display as sRGB (since that is what you embedded when you saved it). At least, you will now see a difference between them. Hence, using monitor RGB as working space is not the same as turning colour management off. The jpeg will show the same when your working space is monitor RGB as it did when the working space was ProPhotoRGB.

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Well, at least I'm glad you see purple and I definitely follow some of what you're saying, but by profiling my monitor and running "ProfileChooser" isn't it loading LUTs into the graphics card and thus making everything I see, even in unprofiled apps, conform visually to the sRGB space?

In that case, if I open something saved in sRGB (with profile embedded, or even not), shouldn't I see the same thing outside of Photoshop/Lightroom (say "Windows Picture and Fax Viewer", heretofore called "WPFV") as inside Photoshop/Lightroom.

Or am I just plain daft (I'm not sure I want you to answer this)?

As an example, here is a screen save of Lightroom on the right with the S5 image, and then on the left a WPFV open of a JPEG conversion with embedded sRGB profile (which, yes, I know WPFV will ignore the profile, but assume sRGB right?):



Now previewing this post with profile correction turned off in Firefox, I see exactly what I see on the screen - the Lightroom image is far more purple than the WPFV image. Now I suspect what you'll see, having a profiled monitor, is the WPFV side looking like the purple I see in Lightroom, but the Lightroom side looking almost magenta since it has shifted so much. From what I can tell, most people see the WPFV version I see when looking at this in an unmanaged browser.

But my point is I would expect both to look the same because the monitor is corrected to sRGB space by the ProfileChooser load and Photoshop would also be using sRGB so the two should be the same.

However, clearly that's not the case.

On the other hand, if people are saying the more saturated purple of the right (Lightroom) is what I would expect to see printed, then I would say, I don't print that much and would rather see what most people are going to see on their monitor since most of what I do is web based.

Gak!

I think I'm going to re-read your post and try to print this to see which version comes out on my printer...

Of course I wish I remembered which of the two versions the plant actually looked like to me (I think the Lightroom version but...).

--
Matt Fahrner
http://www.boinkphoto.com

Here's the full pic saved as a JPEG with sRGB rather than a screen print:



(note this is as much for me as anyone else).

Now the curious thing is when I tell Photoshop to "Save for Web & Devices" what I see is the less purple version that doesn't match what I'm seeing in Photoshop under the normal editing window. The normal editing window looks like the Lightroom version of the previous post. The "Save for Web & Devices" looks like the WPFV version.

Problem is, I don't know which is the right version! However what I want is so that when I save/view for web, it matches the version I see when I'm editing when in Photoshop/Lightroom!

Note the Photoshop/Lightroom version looks much more saturated and the light spots on the petals merge a bit together, whereas the white spots are much more evident on the WPFV version.

I'm soooooooo confused.

--
Matt Fahrner
http://www.boinkphoto.com

scathew said:

....................by profiling my monitor and running
"ProfileChooser" isn't it loading LUTs into the graphics card and
thus making everything I see, even in unprofiled apps, conform
visually to the sRGB space?

Click to expand...

No. The LUT can only alter the gamma curves of the three channels (R, G and B) and set the white point as a combination of the primary R, G and B values. But it cannot alter the values of the primaries themselves. So if, for example, the primary B (blue) of your monitor is displaced towards orange, the LUT cannot correct that. You are stuck with a blue primary that is too orange. LUTs do not mix the channels. However, the display profile measures what the monitor is actually displaying after the application of the LUT. The display profile therefore records that your primary B is too orange. Thus when Photoshop displays an image on your monitor, it shifts the blues away from orange and towards purple.

scathew said:

In that case, if I open something saved in sRGB (with profile
embedded, or even not), shouldn't I see the same thing outside of
Photoshop/Lightroom (say "Windows Picture and Fax Viewer", heretofore
called "WPFV") as inside Photoshop/Lightroom.

Click to expand...

No, for the reason I explain relating to primaries and also because Photoshop does apply the inverse of your measured monitor display profile when it displays the image whereas WPFV does not apply anything at all.

scathew said:

Or am I just plain daft (I'm not sure I want you to answer this)?

Click to expand...

I will and you're not.

scathew said:

As an example, here is a screen save of Lightroom on the right with
the S5 image, and then on the left a WPFV open of a JPEG conversion
with embedded sRGB profile (which, yes, I know WPFV will ignore the
profile, but assume sRGB right?):

Click to expand...

Wrong. WPFV does not assume sRGB. It simply ignores the profile without assuming anything else. It simply throws the image's pixel values straight at the LUT enabled graphics card. If the LUT happens to have achieved a good match to sRGB, the result will be a reasonable approximation to sRGB. But if the primaries are badly displaced, as they almost always are on an LCD display (with the possible exception of the bank breaking Lacies and Eizos), even the LUT adjusted display will not be anywhere near sRGB, since the primary colours will still be shifted.

scathew said:

Now previewing this post with profile correction turned off in
Firefox, I see exactly what I see on the screen - the Lightroom image
is far more purple than the WPFV image. Now I suspect what you'll
see, having a profiled monitor, is the WPFV side looking like the
purple I see in Lightroom, but the Lightroom side looking almost
magenta since it has shifted so much. From what I can tell, most
people see the WPFV version I see when looking at this in an
unmanaged browser.

Click to expand...

What you expect I'll see is pretty much what I do see.

scathew said:

But my point is I would expect both to look the same because the
monitor is corrected to sRGB space by the ProfileChooser load and
Photoshop would also be using sRGB so the two should be the same.

Click to expand...

No because, as I say, the ProfileChooser can only apply the LUT and so cannot correct it to sRGB if the primaries are shifted. But Photoshop can correct for the difference between how the the LUT applied display actually does look and how it ought to look if it were true sRGB. It will still have quite a struggle with badly shifted primaries because it also has to preserve the relationship between the image colours and handle colours out of gamut for the monitor as well as trying to mix the primaries it is presented with. So even Photoshop will not achieve the same result on a primary-shifted monitor as it can on one with better primaries.

scathew said:

On the other hand, if people are saying the more saturated purple of
the right (Lightroom) is what I would expect to see printed, then I
would say, I don't print that much and would rather see what most
people are going to see on their monitor since most of what I do is
web based.

Click to expand...

The print would probably be more like the Lightroom version. As for what most people would see on their monitors, it is more or less impossible to know. People viewing on low end LCDs, which will include virtually all laptops and all but the highest end, most expensive and exotic LCD monitors, will be suffering displaced primaries that cannot be corrected by calibration. Those viewing on good CRTs will see versions closer to what your LR displays.

And people viewing on displays that are uncalibrated see......well, guess.

scathew said:

Gak!

Click to expand...

That's a great word. Very apt.

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I have a home on pbase
http://www.pbase.com/claypaws/
If you have the time to look
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Thank you Claypaws, you have finally allowed me to put this to rest - I understand what's going on now thanks to your post. Makes perfect sense given the inability to truly correct the monitor - I assumed the LUTs could do more than they really could.

In any case, I came up with what I think was a sort of ingenious test to see what the camera took versus what it was (he says patting himself on the back). I took a picture of the monitor showing the image in question here and then imported it into Lightroom.

While there was a bit of shift to blue (actually I just white-balanced off the gray edges and now it's dead to nuts), the image colors and the white petal zones were mostly preserved. That makes me think the version I see in Lightroom is at least relatively accurate to what is actually in front of the camera. That is ultimately probably more important being accurate to what most web viewers will see.

I'm also guessing since most colors seem to be relatively unmangled compared to these purples (and that is looking at multiple managed and unmanged LCDs) that this particular range is a sore spot on LCDs.

A big thanks again for all your help, as well as others who have contributed.

I can now go back to real work who pays for these toys!

--
Matt Fahrner
http://www.boinkphoto.com

And now having understood Claypaws explanation yours also essentially says the same thing, I just didn't get it.

Now I do - thank you very much!

--
Matt Fahrner
http://www.boinkphoto.com

scathew said:

Now the curious thing is when I tell Photoshop to "Save for Web &
Devices" what I see is the less purple version that doesn't match
what I'm seeing in Photoshop under the normal editing window. The
normal editing window looks like the Lightroom version of the
previous post. The "Save for Web & Devices" looks like the WPFV
version.

Click to expand...

Save for web removes the embedded profile by default. So what you are seeing in a save for web version is an unconverted image without colour management. That is exactly what you see in the unmanaged WPFV.

scathew said:

Problem is, I don't know which is the right version! However what I
want is so that when I save/view for web, it matches the version I
see when I'm editing when in Photoshop/Lightroom!

Click to expand...

In that case, use "save as" rather than save for web, and ensure you have ticked the box to include the icc profile. Of course, ensure that you have converted the image to sRGB or are working with sRGB as your RGB working space. The latter is the easiest method to ensure that images will be saved with an embedded sRGB profile.

BTW, CS2 allows you to include an icc profile in a save for web. Not sure which version of PS you have. In any case, "save as" is the way to go as it gives you full control over what you want to do

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******************************************************
I have a home on pbase
http://www.pbase.com/claypaws/
If you have the time to look
******************************************************

scathew said:

Thank you Claypaws, you have finally allowed me to put this to rest -
I understand what's going on now thanks to your post. Makes perfect
sense given the inability to truly correct the monitor - I assumed
the LUTs could do more than they really could.

Click to expand...

You're welcome. Every time I think about this sort of question, I learn a lot by having to think clearly - always difficult!

scathew said:

I'm also guessing since most colors seem to be relatively unmangled
compared to these purples (and that is looking at multiple managed
and unmanged LCDs) that this particular range is a sore spot on LCDs.

Click to expand...

Saturated blues and cyans are close to the boundary of the sRGB gamut, possibly outside it and almost certainly outside the gamut of many LCD displays.

Very saturated colours are also those most obviously affected by shifted primaries.

--
******************************************************
I have a home on pbase
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If you have the time to look
******************************************************