Luminous Landscape Forum
Raw & Post Processing, Printing => Colour Management => Topic started by: Hening Bettermann on January 18, 2010, 01:30:39 pm
-
Hi!
So I have bought this wide gamut monitor and calibrated it with the Eizo software and the DTP94 puck. I have also just made a profile for my 5D2 using the ColorCheckerSG and Argyll_CMS. On my old monitor, a Samsung 193P, the profile gives a very good visual match between the screen image of the 24 patch ColorChecker, displayed in Raw Developer, and the physical chart, illuminated by one of the 2 Solux® lamps that were used to shoot it. But on the Eizo, there is an overall reddish cast, particularly visible in patches row1/column2, 2/1, 2/3 and 2/6.
How can I achieve more correct colors on the Eizo? My main point is not the match between the monitors, but between the Eizo and the chart. If it was the Samsung which was off, I would not care - I had planned to use it for the tools, and home office use. - The Samsung was calibrated with EyeOne software and the same DTP94 year(s) ago.
I have read WillH's advice in thread
http://luminous-landscape.com/forum/index....or*++red*++cast (http://luminous-landscape.com/forum/index.php?showtopic=38135&hl=calibrat*++Wide++gamut++monitor*++red*++cast)
but this refers to NEC software. I can not see these options in the Color Navigator.
This is on Mac Pro Nehalem 2.66 GHz running 10.6.2.
Hoping for your help - again... Hening.
-
So I have bought this wide gamut monitor and calibrated it with the Eizo software and the DTP94 puck. ...
what are your targets for profiling (white point, luminance, gamma/trc)?
-
what are your targets for profiling (white point, luminance, gamma/trc)?
Hi tho_mas, white point is 6500, luminance 100 cd, gamma 2.2.
-
Hi tho_mas, white point is 6500, luminance 100 cd, gamma 2.2.
hmh, I think this should be within the realms of possibility ...
Hard to say without seeing the screen.
What if you edit the white point in Color Navigator manually to match a neutral white on your color checker under the Solux lamps visually?
Color Navigator->Detail->Adjust manually.
After the manual adjustment Color Navigator measures again to correct the profile; so you can only adjust manually with the DTP94 connected.
I'd note the resulting white point - so the XY values.
Afterwards I would create a new target with 100cd/m2, gamma 2.2 and the respective XY values as white point.
This is what I do and it works perfectly (though with a CG241W).
And set the priority to "gray balance" not to "contrast".
-
Thank you tho_mas, I'll try this ASAP.
-
Hi,
What about synthetic CC card? Try downloading this:
http://www.brucelindbloom.com/downloads/Co...culator.tif.zip (http://www.brucelindbloom.com/downloads/ColorCheckerCalculator.tif.zip) and open in Photoshop.
Compare with your CC card. Do you see the same problem?
Best regards
Erik
Hi!
So I have bought this wide gamut monitor and calibrated it with the Eizo software and the DTP94 puck. I have also just made a profile for my 5D2 using the ColorCheckerSG and Argyll_CMS. On my old monitor, a Samsung 193P, the profile gives a very good visual match between the screen image of the 24 patch ColorChecker, displayed in Raw Developer, and the physical chart, illuminated by one of the 2 Solux® lamps that were used to shoot it. But on the Eizo, there is an overall reddish cast, particularly visible in patches row1/column2, 2/1, 2/3 and 2/6.
How can I achieve more correct colors on the Eizo? My main point is not the match between the monitors, but between the Eizo and the chart. If it was the Samsung which was off, I would not care - I had planned to use it for the tools, and home office use. - The Samsung was calibrated with EyeOne software and the same DTP94 year(s) ago.
I have read WillH's advice in thread
http://luminous-landscape.com/forum/index....or*++red*++cast (http://luminous-landscape.com/forum/index.php?showtopic=38135&hl=calibrat*++Wide++gamut++monitor*++red*++cast)
but this refers to NEC software. I can not see these options in the Color Navigator.
This is on Mac Pro Nehalem 2.66 GHz running 10.6.2.
Hoping for your help - again... Hening.
-
Hi!
Erik, thank you for the tip with the synthetical CC. With it, the experience is slightly different: on the Samsung, the match with the chart is good (and better than with the camera image); on the Eizo, the look is overall muddy, but with a good match to the chart with the Solux® lamp turned off or dimmed; that is in diffuse (cloudy) wintery noon daylight from a window 3 meters away and snow outside. In this comparison, the chart image does not look "more reddish"; but the mud makes comparison invalid.
The difference between the monitors is also very clearly seen with the Desktop set to solid light gray, as I have on both monitors.
The Samsung was calibrated to max brightness, which was 122 cd. On the Eizo, the muddy look of the CC does not change at all when I choose the 120 (or 80) cd profile which I also made.
What can I conclude from this so far? Obviously, to use the synthetic CC for comparing monitors rather than the camera image. Beyond that? How come that the CC looks more muddy on the Eizo?
I have a feeling that it might be a good idea to do the visual white point adjustment of the monitor in darkness.
Thank you both for your interest. - Hening.
-
Hi,
One thing you may consider is which color space you use. For a time I had an iMac 24" and an Eizo FlexScan SX2461W side by side. The iMac 24" was much brighter. Now, my Eizo was using Adobe RGB while the iMac was using sRGB. I also made the Eizo darker as the iMac was a bit to bright to match my prints, and couldn't be made darker. Both were calibrated using my ColorMunki, clearly shaking my belief in calibration. I think I could match my iMac on the Eizo by using sRGB and increasing brightness.
Coming back to the Macbeth (sorry I mean X-rite) color charts. The problem is that when you take a picture of a CC-card the picture will have a tone curve applied to enhance contrast. It's nice for the eye but makes comparison harder. That's the reason I recommend a synthetic target.
Best regards
Erik
Hi!
Erik, thank you for the tip with the synthetical CC. With it, the experience is slightly different: on the Samsung, the match with the chart is good (and better than with the camera image); on the Eizo, the look is overall muddy, but with a good match to the chart with the Solux® lamp turned off or dimmed; that is in diffuse (cloudy) wintery noon daylight from a window 3 meters away and snow outside. In this comparison, the chart image does not look "more reddish"; but the mud makes comparison invalid.
The difference between the monitors is also very clearly seen with the Desktop set to solid light gray, as I have on both monitors.
The Samsung was calibrated to max brightness, which was 122 cd. On the Eizo, the muddy look of the CC does not change at all when I choose the 120 (or 80) cd profile which I also made.
What can I conclude from this so far? Obviously, to use the synthetic CC for comparing monitors rather than the camera image. Beyond that? How come that the CC looks more muddy on the Eizo?
I have a feeling that it might be a good idea to do the visual white point adjustment of the monitor in darkness.
Thank you both for your interest. - Hening.
-
I have to add to the above, that the monitor gray looks *lighter* on the Eizo with 100 cd than on the Samsung with nominal 120. I assume that aging is the reason.
Now it is dark in my part of the woods, and I make new discoveries.
The Desktop set to dark gray on both monitors.
4 copies of the synthetic CC opened in PS and Preview respectively on the 2 monitors and compared to the physical CC illuminated by 1 Solux lamp, in the otherwise dark room, show this:
PS CS3:the Eizo image looks more muddy (than the chart and than the Samsung image) in most patches, in particular in patch 3/2 (green), 3/3 (red) and 3/5 (magenta). Patches 1/6 (bluish green) and 2/5 (yellow green) look pale (under-saturated).
Preview: The Samsung image is the one that comes closest to the chart, of all the 4. The Eizo edition is slightly more reddish, but not muddy at all. The reddish cast is in particular visible in patch 2/1 (orange) and 2/3 (moderate red). And also in patch 1/2 (light skin); here, it makes the Preview/Eizo image the best of the quartet.
The PS/Eizo image is way out muddy and impossible. All the other 3 are closer to each other and the chart, Preview/Samsung being the best, but all 3 would be acceptable.
I find it very difficult to judge the gray scale in comparison to the chart.
So when adjusting the White Point manually, I tried to match the monitor (light) gray of the Samsung. That was impossible. Then I tried to match the CC image with the chart, looking at the color patches more than the gray scale. I found it very very difficult. At last, I found that I got the best result by setting all: R, G and B to 100%! The profile created with this new target has a color temperature of 7008 K! And both the monitor gray and the CC images are just as before. Is this software just pretending?
Remaining questions:
-1-Should I try a different software? The Samsung was calibrated with ColorEyes. I would have to buy a new license, since my version does not run under Snow Leopard.
-2-Why is the PS image so muddy on the Eizo?
Sigh! - Hening.
I see that in the meantime you (Erik) have written a new answer, which however I do not understand: The color spaces appear in the same menu as the profiles, I can only choose one. ? Otherwise, I use ProPhoto whereever I have the choice. - I have used the synthetic target, as you may see in my "log" above.
-
This appears to be either a corrupt calibration profile or the numbers derived from the colorimeter's measuring of the display and written within the profile's matrix formula are inaccurate. Henning's initial description of the appearance of the X-rite hues in certain patches seems to suggest this, but it could be caused by the tone curve default suggested by Erik.
Also some versions/brands of calibration packages have colorimeter filters/software driver that may not be tuned to give an accurate measurement of one particular display inducing it to come up with a messed up set of matrix formulas that affects only some colors.
To get an idea if the matrices are messed up if on a Mac that allows the DigitalColor Meter to be set to CIELab readouts, you'll be able to test if it's a matrix issue either on the synthetic or the original shot by taking LAB readings from DCM.
I actually did this to get the source Raw image used to create the DNG profile for my Pentax K100D DSLR to actually deliver the Lab readings included with my X-rite CCchart to see if the LAB readings give an accurate representation on a display. After some extreme edits in ACR using these Lab readings to guide me, I got a very exact visual match to the original as demonstrated in the screenshots below.
Unfortunately I can't apply those LAB based preset edits derived from the Lab corrected CCchart to other Raw images without even further additional edits. Just applying the DNG profile to ACR's default was enough but keeping in mind how contrast can affect hue/saturation so critically to guide my edits visually.
[attachment=19572:CCchartA...Gprofile.jpg]
[attachment=19573:CCchartC...rLabEdit.jpg]
-
Hi,
The Eizo has different presets for color spaces. I don't know how to set because I have a much simpler model. But it does support both sRGB and nearly Adobe RGB. Choosing sRGB mode may be an option. You obviously need to reprofile once settings are changed. The setting I talk about is on the monitor.
Regarding sRGB vs. Adobe RGB, it's said that there are advantages to both. I'm not advocating either but it could be helpful to have the same color space when comparing two monitors.
Regarding ColorEyes I'd suggest that you could try a demo license. I think it's usable for a few days. I think that the Color Eyes gives some dE values? That could be helpful.
Best regards
Erik
I have to add to the above, that the monitor gray looks *lighter* on the Eizo with 100 cd than on the Samsung with nominal 120. I assume that aging is the reason.
Now it is dark in my part of the woods, and I make new discoveries.
The Desktop set to dark gray on both monitors.
4 copies of the synthetic CC opened in PS and Preview respectively on the 2 monitors and compared to the physical CC illuminated by 1 Solux lamp, in the otherwise dark room, show this:
PS CS3:the Eizo image looks more muddy (than the chart and than the Samsung image) in most patches, in particular in patch 3/2 (green), 3/3 (red) and 3/5 (magenta). Patches 1/6 (bluish green) and 2/5 (yellow green) look pale (under-saturated).
Preview: The Samsung image is the one that comes closest to the chart, of all the 4. The Eizo edition is slightly more reddish, but not muddy at all. The reddish cast is in particular visible in patch 2/1 (orange) and 2/3 (moderate red). And also in patch 1/2 (light skin); here, it makes the Preview/Eizo image the best of the quartet.
The PS/Eizo image is way out muddy and impossible. All the other 3 are closer to each other and the chart, Preview/Samsung being the best, but all 3 would be acceptable.
I find it very difficult to judge the gray scale in comparison to the chart.
So when adjusting the White Point manually, I tried to match the monitor (light) gray of the Samsung. That was impossible. Then I tried to match the CC image with the chart, looking at the color patches more than the gray scale. I found it very very difficult. At last, I found that I got the best result by setting all: R, G and B to 100%! The profile created with this new target has a color temperature of 7008 K! And both the monitor gray and the CC images are just as before. I this software just pretending?
Remaining questions:
-1-Should I try a different software? The Samsung was calibrated with ColorEyes. I would have to buy a new license, since my version does not run under Snow Leopard.
-2-Why is the PS image so muddy on the Eizo?
Sigh! - Hening.
I see that in the meantime you (Erik) have written a new answer, which however I do not understand: The color spaces appear in the same menu as the profiles, I can only choose one. ? Otherwise, I use ProPhoto whereever I have the choice. - I have used the synthetic target, as you may see in my "log" above.
-
Hi again, and thank you all for your concern.
@ Erik: Now I see, the Color Mode button allows me to choose between a handful of color spaces including sRGB, plus Custom plus 3 Calibration sets. However, I am reluctant to use sRGB. I have spent about 2,000 EURO to get a wider gamut, and I want to use it. My main concern is not the match between the monitors, but the match between the best monitor and the chart.
The Eizo software, too, can save a validation report with DeltaE values. For the original profile, these were: (dE2000):average 0.2, max 0.6, dE White Point 0.3
For the profile I created with the new target: average 0.2, max 0.7, dE White Point 0.2.
So my manual White Point is slightly better by the numbers, but I can not see the difference. Also a White Point of 7000 K worries me.
@ tlooknbill:
> Also some versions/brands of calibration packages have colorimeter filters/software driver that may not be tuned to give an accurate measurement of one particular display inducing it to come up with a messed up set of matrix formulas that affects only some colors.
Hm, this was the Color Navigator software supplied with the monitor, and a supported puck. Of course, the puck might be damaged...??
I can not quite look through how the Lab values come in. When trying to compare them to reference values given on Bruce Lindbloom's site, I don't know which reference illuminant to choose and which RGB model. Anyway, here are the values for the 1. row of the synthetic CC, + the neutral gray patch. Both opened in PSCS3 and Preview, respectively. Can you see anything on these values? And why is the PS image so muddy?
------------
Eizo screen, Bruce Lindblooms synthetic CC target, L*a*b* readings from Apple Digital Color Meter
CC patch number - L - a - b
image opened in PSCS3, working color space ProPhoto
1 33.019 10.316 14.719
2 62.745 13.340 18.203
3 46.722 -4.062 -21.023
4 38,099 -8,859 18,711
5 51,778 6,930 -24,883
6 67,871 -23,098 0,953
22 47,375 0,277 1,387
image opened in Preview
1 37,923 14,371 16,523
2 66,448 16,617 18,449
3 50,304 -4,383 -21,383
4 43,343 -13,555 21,438
5 55,486 9,488 -24,234
6 70,723 -31,645 0,605
22 51,427 0,273 1,344
---------------------------------------------
Hening.
-
Hi!
The Delta E values you measure seem to be pretty good. The dE values you see are very good. I read a rule of thumb is that differences below dE 5.0 are hard to see. The difference between the LAB values in "preview" and CS3 is something I don't understand. I might look into this a bit more in a couple of days but I don't have the energy right now. It's a pity that folks like the Digital dog don't chime in (or would it be bark in? :-) on this discussion.
One thing you may consider. Eizo monitors are said to be well calibrated from factory, could you just use factory presets and profiles from Eizo and see what it looks like?
Best regards
Erik
Hi again, and thank you all for your concern.
@ Erik: Now I see, the Color Mode button allows me to choose between a handful of color spaces including sRGB, plus Custom plus 3 Calibration sets. However, I am reluctant to use sRGB. I have spent about 2,000 EURO to get a wider gamut, and I want to use it. My main concern is not the match between the monitors, but the match between the best monitor and the chart.
The Eizo software, too, can save a validation report with DeltaE values. For the original profile, these were: (dE2000):average 0.2, max 0.6, dE White Point 0.3
For the profile I created with the new target: average 0.2, max 0.7, dE White Point 0.2.
So my manual White Point is slightly better by the numbers, but I can not see the difference. Also a White Point of 7000 K worries me.
@ tlooknbill:
> Also some versions/brands of calibration packages have colorimeter filters/software driver that may not be tuned to give an accurate measurement of one particular display inducing it to come up with a messed up set of matrix formulas that affects only some colors.
Hm, this was the Color Navigator software supplied with the monitor, and a supported puck. Of course, the puck might be damaged...??
I can not quite look through how the Lab values come in. When trying to compare them to reference values given on Bruce Lindbloom's site, I don't know which reference illuminant to choose and which RGB model. Anyway, here are the values for the 1. row of the synthetic CC, + the neutral gray patch. Both opened in PSCS3 and Preview, respectively. Can you see anything on these values? And why is the PS image so muddy?
------------
Eizo screen, Bruce Lindblooms synthetic CC target, L*a*b* readings from Apple Digital Color Meter
CC patch number - L - a - b
image opened in PSCS3, working color space ProPhoto
1 33.019 10.316 14.719
2 62.745 13.340 18.203
3 46.722 -4.062 -21.023
4 38,099 -8,859 18,711
5 51,778 6,930 -24,883
6 67,871 -23,098 0,953
22 47,375 0,277 1,387
image opened in Preview
1 37,923 14,371 16,523
2 66,448 16,617 18,449
3 50,304 -4,383 -21,383
4 43,343 -13,555 21,438
5 55,486 9,488 -24,234
6 70,723 -31,645 0,605
22 51,427 0,273 1,344
---------------------------------------------
Hening.
-
Hi again.
Using the Eizo default profile gives the same picture, except that the images are slighlty lighter overall; the difference between the Preview and the PS rendering however is largely the same. As before, the PS image comes closer to the physical chart as I dim the Solux lamp.
It seems to me that there are 2 different problems here: One is the slightly reddish cast on the Eizo; the second is the dim look of the PS image on the Eizo, which differs significantly both from the PS look on the Samsung and the Preview look on the Eizo.
Could the reason be that it is a part of the not-full support of CS3 for Snow Leopard, that PS fails to convert from its own working space to the monitor profile, and that this makes more of a difference on the wide gamut monitor? - No, the pattern is the same if I set the PS working space to Adobe or even sRGB.
I tried ColorEyes yesterday night, but it got stuck. Maybe I'll try again tonight, but since my profile seems to be so good by the numbers, I have little hope that it will make the difference.
Good light! - Hening.
-
The Lab numbers you posted from both Preview and CS3 are quite a bit off compared to the numbers I get in Preview, CS3 and DigitalColor Meter on my chart which all match up on my 2004 G5 iMac in OS 10.4.11 calibrated with the original i1 Display and EyeOne Match 3.6.2, not i1 Display 2. My numbers are based on an averaging of several CC charts created by Babelcolor that can be found in this pdf:
http://www.babelcolor.com/download/RGB%20C...olorChecker.pdf (http://www.babelcolor.com/download/RGB%20Coordinates%20of%20the%20Macbeth%20ColorChecker.pdf)
This page:
http://forums.imatest.com/index.php?topic=709.0 (http://forums.imatest.com/index.php?topic=709.0)
shows how other owner's CC chart appear which are quite close to what I got.
Frankly that's not the real issue anyway. The fact as Erik pointed out you are getting two different Lab readouts between Preview and CS3 which are both color managed is an indicator the profile is either corrupt or inaccurate or something isn't right with your setup.
Right now I'ld suggest you not use your Solux lit chart to troubleshoot this problem and stick with a synthetic preview made from known Lab numbers you can verify between the two apps in order to eliminate variables between your camera, DNG profiling and the display calibration in order to get this sorted out.
It might help if you could post a screenshot of this red that shows up in the CC chart on the Eizo mentioned in your initial post and a screenshot viewed with the Samsung.
-
Hi again!
In order to make these screen shots more comparable, I made a new profile for the Eizo, trying to match the desktop light gray of the Samsung. I set the luminance to 80 cd and came pretty close:
Digital Color Meter Lab reading of Desktop Light Gray:
Samsung 87,059 - 0 - 0
Eizo 86,981 - 0 - 0
Also, I chose L* rather than gamma 2.2. The Samsung was calibrated with ColorEyes, and ColorEyes recommends L*, and even if I have no record of it, I believe I followed the recommendation.
BTW I can see a slight green-to-red gradient in the gray on the Eizo, but Digital Color Meter can not measure it.
The Samsung profile had delta E average 0.37, max 0.68. The Eizo has average (dE2000) 0.2, max 0.5, dE White Point 0.4
The screenshots are from Bruce Lindbloom's synthetical ColorChecker target, opened in Preview and PSCS3, and displayed on either monitor.
Comparing the Preview images, I find a red cast on the Eizo, see patches 1/2, 2/1, 2/3, 2/6. Much grosser however is the dull appearance of the PS Eizo image compared to the other 3.
Bruce Lindbloom's reference values for his synthetic CC for Illuminant D65,
rounded down to 3 post-comma digits:
row 1 and patch 22, middle gray;
37,257 12,766 14,869
65,959 13,500 17,224
50,585 -1,609 -21,263
43,188 0,433 21,970
55,662 11,1813 -25,010
71,232 -31,861 1,507
51,244 -0,076 0,687
Lab readings of
Preview on Samsung, row 1 and patch 22
37,841 13,996 16,410
65,943 15,648 18,121
50,205 -4,762 -21,539
43,119 -13,723 21,371
55,424 9,430 -24,691
70,771 -31,648 0,043
51,415 0,207 1,195
PS on Samsung
36,945 13,621 15,699
65,943 15,648 18,121
49,673 -5,395 -21,770
42,382 -13,555 20,383
54,841 8,711 -25,008
70,343 -31,891 -0,016
50,921 -0,199 1,039
Preview on Eizo
37,856 14,223 16,383
66,566 16,609 18,820
50,289 -4,430 -21,598
43,326 -13,895 21,723
55,375 9,785 -24,852
70,835 -31,645 0,414
51,431 0,273 1,273
PS on Eizo
35,450 10,102 14,371
64,199 12,328 17,441
49,044 -2,684 -20,504
40,923 -9,305 18,969
54,014 6,363 -23,422
69,551 -21,277 0,984
49,514 0,277 1,277
[attachment=19650:CC_Previ...ung.tiff.jpg]
[attachment=19648:CC_PS_Samsung.tiff.jpg]
[attachment=19649:CC_Previ...izo.tiff.jpg]
[attachment=19647:CC_PS_Eizo.tiff.jpg]
----------------------------------------------------------
Have a nice week-end! - Hening.
-
I extracted the embedded profile of one of your screenshot images and got a large 720K LUT based file named "193P_dig_max-native.icc". The screenshot of Colorsync Utility shown below shows the "vcgt" tag curves applied to the video card to correct nonlinearity and color cast down the entire grayscale of the native response of your display. These RGB vcgt curves are having to do way too much work for an 8 bit video system.
Also the gamut shown on the right is much smaller than sRGB and I know Eizo/Samsung? wouldn't put out a high quality display with this size gamut. I can only surmise your profile is toast.
My only suggestion is for you to recalibrate and profile by first loading a 21 step grayramp spanning the entire display and set brightness and contrast with the display's buttons to get this grayramp to look as perfect as possilble with the sRGB2.1 profile loaded as your system profile.
Then go through the calibration process by setting gamma 2.2, white point brightness to match the Samsung's and build a simple matrix profile to where the final profile is way under 720K, more like around 10K and use native color temp and just measure the response and build the profile.
That table based profile you made is messed up. You might want to try using some other calibration software that works with your colorimeter.
[attachment=19692:BadEizoProfileLL.jpg]
Strangely everyone of those screenshots you posted has the Samsung 193 profile embedded. Could it be that your Eizo is using the Samsung profile?
-
Its normal, I had the same issue of the reddish cast with my CG241W when I first bought it, and went crazy to solve the problem, just like you, but it went away within 2-3 weeks of use. I think it has with the burn-in period for a monitor. FYI I also use the ColorEyes software and the DPT94. I get identical results calibrating with either the CE or Color Navigator software.
-
Strangely everyone of those screenshots you posted has the Samsung 193 profile embedded. Could it be that your Eizo is using the Samsung profile?
If you're running dual monitors, it's best to have separate video card for each monitor, otherwise you can run into a situation where one profile is always being used for both monitors, regardless of settings, profiling methods, etc. That may well be what is happening here. The messed-up non-linear table profile is a strong indication that something along those lines is happening; all of the Eizos I've profiled have had very linear TRC curves.
-
If you're running dual monitors, it's best to have separate video card for each monitor, otherwise you can run into a situation where one profile is always being used for both monitors, regardless of settings, profiling methods, etc. That may well be what is happening here. The messed-up non-linear table profile is a strong indication that something along those lines is happening; all of the Eizos I've profiled have had very linear TRC curves.
Not really the case with Macs!
-
Not really the case with Macs!
PC/Mac doesn't matter. If your video card has dual outputs but only a single LUT, (which many do), then that LUT is used for both monitors regardless of any other settings--it's a hardware limitation. Dual cards guarantees that each monitor has its own LUT and can be separately profiled.
-
PC/Mac doesn't matter. If your video card has dual outputs but only a single LUT, (which many do), then that LUT is used for both monitors regardless of any other settings--it's a hardware limitation. Dual cards guarantees that each monitor has its own LUT and can be separately profiled.
Maybe, but I've been using dual monitors on different macs with single cards for years and never had any issues.
-
Maybe, but I've been using dual monitors on different macs with single cards for years and never had any issues.
You've simply been lucky enough to have used dual-LUT cards.
-
PC/Mac doesn't matter. If your video card has dual outputs but only a single LUT, (which many do), then that LUT is used for both monitors regardless of any other settings--it's a hardware limitation. Dual cards guarantees that each monitor has its own LUT and can be separately profiled.
This 2005 Colorsync Mailing List discussion reply by Peter Karp indicates you're sort of right:
http://lists.apple.com/archives/colorsync-...b/msg00062.html (http://lists.apple.com/archives/colorsync-users/2005/Feb/msg00062.html)
But frankly there's a lot of confusing terminologies in discussions like these to describe internal components of a display profile that I wish would be made more clear. For instance the term "LUTs" often get interchanged with "VCGT", "TRC's", "Table based as opposed to matrix based version of a profile (both have different file sizes)" and "Gamma Curves". That Colorsync discussion doesn't make it any more clear what's really getting downloaded to the video card either.
From my understanding a Mac profile has a "VCGT"-(Video Card Gamma Tag) which contains ONLY the separate RGB curves that work out all the little kinks in a display's measured response compared to a forced target response. If the display's response is already close to target (i.e. 6500K, 2.2 gamma, XXX cd/m2 luminance and neutral in all 255 gray levels) which most displays already are these VCGT RGB curves will almost resemble a straight line. These curves are what make each display change slightly in color cast and contrast globally outside of color managed apps whenever you click on different profiles in the Display Preference panel.
I can confirm on my 2004 G5 iMac with an external Dell 2209WA each display's corresponding "VCGT" curves within their given profiles are occupying the same video card. To confirm this I have both the sRGB standard profile chosen for both displays which doesn't have a "VCGT" clearing the correction from the video card and each display show differences in color cast and contrast but only slightly. VCGT is not a TRC curve which is just a simple 2.2 gamma curve used only by CM apps in case an image is tagged with a working space containing a gamma curve other than 2.2 like the 1.8 gamma of ProPhotoRGB.
What I'm not clear on is the term "Table" based profile as opposed to "Matrix" based. From examining the Samsung embedded profile's table section on this in Colorsync Utility it appears to be a more complicated set of individual matrix transform formula's.
The issue here is figuring out if Hening's red cast in select colors is caused by the VCGT or bad matrices written into the profile causing color managed apps to screw with hue/sat or a combination of both.
He first needs to confirm how each profile is being assigned to each display on his setup which he hasn't done.
-
Thank you all for your concern!
ddk, what you write is a great consolation! I have so far avoided to use the Eizo for trivia (=non-photography) to keep the mileage down on this precious instrument, but I'll change that now...
Concerning the dual profile and 1 videocard: When I open the display prefs, the profile i chose is selected for either monitor. I can flip through all the (canned) profiles on either monitor and see corresponding changes on that monitor only. E.g if I choose the Samsung profile for the Eizo, the Desktop light gray on the Eizo changes towards greenish. Wouldn't this indicate that the card is capable of handling 2 profile output?
(It's a NVIDIA GeForce GT 120).
Then why is the Samsung profile embedded in all my screenshots ? Could it have something to do with the fact that they are screenshots, i.e. have gone through Grab (the screenshot utility on the Mac)? Bruce Lindblooms synthetical CC, which is a .tif and the basis of all the screenshots, has Lab embedded as the color space, according to the Mac's Get Info command. Could it be that Grab embeds the profile of the "primary" monitor, i.e. the one that holds the menu bar? It is very likely that this was the Samsung when I took the shots.
Yes exactly! When I open the synthetic CC in Preview and save the image, Get Info still shows Lab as the color space. When I take a screenshot of the Preview image with Grab on the Eizo, with the Eizo holding the menu bar, and save the image, Get Info shows "Color space: RGB, Color profile: CG243W" (The factory profile, which is currently selected). This does not change if I move the open image to the Samsung when I take the shot. - One mystery solved!
If it is just the Samsung profile which is damaged, that's no problem. IF the Eizo really looses the red cast before all too long, I don't care for color accuracy on the Samsung.
In the meantime, I may try to make new profiles for the Eizo with the native White Point, which seems to give the most neutral white.
Concerning profiling software: The downloaded trial of Color Eyes does not run on my Mac, it stops with error #1 or -1. The support has advised deleting the prefs and repairing permissions, which I have done to no avail. Anyway, it seems that is not the Eizo profiling software which is the problem. Also I am befriending Argyll CMS despite the Unix surface.
What is left?
1- I am shocked to read that sRGB is my System color space. I have never chosen that. Where is this shown, and how can I change it?
2- What is wrong with muddy Photoshop?
3- Even if my video card can handle 2 profiles: In the end, I want a high end LUT profile for the Eizo. So if such profiles are too large for the NVIDIA, I am willing to invest in a card that can handle one. Could you recommend a card?
I wrote the above before I had seen post #24 or studied the link to the ColorSync discussion, which I probably will have difficulties to follow, so I better kick this out now.
Best regards - Hening.
-
From what you indicated everything checks out with the way the system is handling two profiles on one video card. You just didn't supply us with the Eizo screenshots containing the custom profile that makes the preview of the synthetic CC reddish. The previous screenshots with the embedded Samsung looked and measured OK.
The only thing left is to recalibrate and build a profile that is a simple matrix (not a large LUT/table based) profile to see if that changes anything.
If your current video card is a third party upgrade installed version as opposed to the one that came with your system when you bought it, you probably should update the driver if there's one available.
1- I am shocked to read that sRGB is my System color space. I have never chosen that. Where is this shown, and how can I change it?
Don't know where you got that idea. You may have got this confused with my mentioning before you recalibrate, to load the sRGB2.1 profile to get an idea how close your display's native response before calibration to the ideal target of 6500K, 2.2 gamma with no multi-colored tints throughout a grayramp really looks. Loading the sRGB2.1(not Apple's sRGB) profile will clear the "Gamma Tables"/"VCGT"/"Calibration Curves" (see how confusing-there's already three names for this one profile component) which is what your calibration software is going to do anyway before it measures the response of your display.
It's not necessary to load the sRGB2.1 profile. Sorry for confusing you.
3- Even if my video card can handle 2 profiles: In the end, I want a high end LUT profile for the Eizo. So if such profiles are too large for the NVIDIA, I am willing to invest in a card that can handle one. Could you recommend a card?
This isn't a question about whether your video card can handle a large LUT profile. Your video card is just fine.
To make this simple just examine your custom high end LUT Eizo profile in Colorsync Utility by double clicking on it which will bring up a separate panel. Scroll down and click on the 'vcgt' line entry and look at each RGB "Gamma Table" curve. It should be a straight line or close to it. It shouldn't look like the Samsung's as shown in my previous post.
-
Bad news.
>You just didn't supply us with the Eizo screenshots containing the custom profile that makes the preview of the synthetic CC reddish.
I had meant to do this, but can now see, that #3 and 4 were useless, since they had the Samsung profile embedded.
So here are new screenshots with different profiles. All have the correct profile embedded, i.e. the shots of the Eizo were taken when the Eizo was the monitor holding the menu bar, and accordingly on the Samsung (it requires a restart of the system to make Grab recognize the shift and embed the correct profile).
All LUT profiles. Color Navigator does not seem to have an option for a matrix profile, and after some hours of fiddling with Argyll, I take a break from that. In the end, I want a LUT profile anyway.
In the vcgt panel, all profiles have 100% straight lines in all 3 colors.
Here goes:
1- Preview on Eizo, gamma 2.2, WP target 6500K
2- Preview on Eizo, L*, WP target 6500K
3- Preview on Eizo, L* with the native WP of the monitor. (~7000K)
4- Photoshop on Eizo, gamma 2.2, WP target 6500 K
5- Photoshop on Eizo, L*, WP target 6500K
6- Photoshop on Eizo, L*, with the native WP of the monitor. (~7000K)
7- Preview on Samsung, with the SyncMaster default profile.
8- Photoshop on Samsung, with the SyncMaster default profile.
9- Preview on Eizo, default profile
10-Photoshop on Eizo, default profile
Conclusion:
My first observation, that led me to start the topic, was invalid because my comparison was based on a damaged profile on the Samsung side.
Now, with the SyncMaster default profile, compared to all Eizo profiles, my picture when comparing the screenshots is this:
All look good (that is: close to the physical chart in Solux light) overall when displayed on the Samsung. Photoshop has the edge in that it avoids the oversaturation of red in patch 2/3. Patch 2/1 is very slightly reddish in all. All fail to render the purple in patch 2/2.
When displayed on the Eizo, all look so muddy overall that the rest is not worth while.
It makes no difference if I choose a profile with 100 rather than 80 cd/m^2 max luminance (no screenshots of this). Even with the default SyncMaster profile on the Samsung, there is still a good brightness match of Desktop light gray, both visually and by Lab numbers. (Samsung: 87.045/0/0, Eizo: 86.981/0/0). The Eizo looks more reddish, but the Digital Color Meter obviously can not see it.
Do I have to return the screen??
:-(
Good light! - Hening.
[attachment=19749:1_Ei_Pr_...00K.tiff.jpg]
[attachment=19750:2_Ei_Pr_...00K.tiff.jpg]
[attachment=19751:3_Ei_Pr_...00K.tiff.jpg]
[attachment=19752:4_Ei_PS_...00K.tiff.jpg]
[attachment=19753:5_Ei_PS_...00K.tiff.jpg]
[attachment=19754:6_Ei_PS_...00K.tiff.jpg]
[attachment=19755:7_Sa_Pr_...ult.tiff.jpg]
[attachment=19756:8_Sa_PS_...ult.tiff.jpg]
[attachment=19757:9_Ei_Pr_...ult.tiff.jpg]
[attachment=19758:10_Ei_PS...ult.tiff.jpg]
---------------------------------------------------------------------------
-
All those screenshots look identical viewed in Preview on my system. They all look correct. DigtitalColor Meter LAB readouts are within specs and there is no red cast. However, for some reason they won't open in Photoshop because I get an error warning stating "Can't complete your request because of an unknown or invalid JPEG marker type is found".
Also both custom profiles embedded in those screenshots ARE simple matrix based, but with NULL vcgt meaning this type of curve is not correcting for any global visual inaccuracies in your display's contrast and neutrality. You're seeing your display's raw native response.
It doesn't matter anyway because this is just getting too complicated troubleshooting over the web.
The important point you made is you say your Eizo Photoshop previews of the synthetic CC is muddy but not in Preview which suggests Photoshop is not using the custom Eizo profile. Go into Photoshop's Color Settings scroll up within the RGB Working Space menu and check to see if "Monitor RGB..." shows the name of your custom profile.
If it doesn't, then you have other unknown software issues you have to deal with which are too difficult to solve here.
Also don't expect a DSLR capture of the CC chart to look exact shot under Solux lights without considerable editing because this light's halogen underpinnings throws off camera's WB sensors. Stick with the synthetic CC chart to make critical assessments of your display calibration/profile.
Sorry I can't help you any further.
-
Thank you for your extensive reply!
> [the screenshots] won't open in Photoshop because I get an error warning stating "Can't complete your request because of an unknown or invalid JPEG marker type is found".
They will open if you remove the fake .jpeg extension so the .tiff is revealed. (The LL software requires jpegs, but *converting* to jpeg even with the lowest quality setting will *IN*crease file size from ~70 to ~100 kB when done in PS, which I knew from an earlier instance. First now, when I check this, I see that converting in Preview will *de*crease the file size to ~30 kB. Also, in this case, converting with one of the involved apps would have added yet another layer of confusion which I could not look through).
>Also both custom profiles embedded in those screenshots ARE simple matrix based, but with NULL vcgt meaning this type of curve is not correcting for any global visual inaccuracies in your display's contrast and neutrality. You're seeing your display's raw native response.
Does this mean these profiles do nothing at all?? Would mean that the CN software is just faking? I don't understand. I think you wrote earlier that these curves "should be a straight line or close to it." ??
>The important point you made is you say your Eizo Photoshop previews of the synthetic CC is muddy but not in Preview which suggests Photoshop is not using the custom Eizo profile.
No what I wrote was
>All look good [...] overall when displayed on the Samsung. [...] When displayed on the Eizo, all look so muddy overall that the rest is not worth while.
Since it is an overall muddy look even more than the red cast in some patches, I made a new profile with a max luminance of 120 cd, but it makes now visual difference whatsoever.
>Go into Photoshop's Color Settings scroll up within the RGB Working Space menu and check to see if "Monitor RGB..." shows the name of your custom profile.
Thank you for this tip! That menu shows Generic RGB profile, + the profile of the monitor which holds the menu bar. So this seems ok.
> Also don't expect a DSLR capture of the CC chart to look exact shot under Solux lights without considerable editing because this light's halogen underpinnings throws off camera's WB sensors. Stick with the synthetic CC chart to make critical assessments of your display calibration/profile.
You may misunderstand me. I am not comparing the screen display of the synthetic CC to screen displays of camera images of the CC, but to the physical chart on my desktop lit by a Solux lamp. When comparing 2 monitors, I think I need a "third opinion".
Is there any better light source for a reasonable price? I chose the Solux according to Bruce Frasers book on Color Management.
> Sorry I can't help you any further.
Thank you very much for your help so far!
-----------------------------------------------------------------------
New discovery:
When I drag my monitor closer to the balcony door and compare the screen image to the CC chart viewed in diffuse daylight under an overcast sky, then the Eizo image is close to the chart! In this light, the chart *does* look muddy. The Samsung looks clearer and thus prettier, AND this is closer to the chart lit by a Solux lamp. The Eizo's native white point of 7 000 K (which I have chosen for the actual profile) is probably close to todays overcast daylight. But what if I view the chart in clear sunshine in the late afternoon? (My typical shooting light). The other way round: What does the synthetical chart look like when I make a monitor profile with a target white point of 5 000 K and compare that to the physical chart? -> Just as muddy.
So what am I to believe??
-
So what am I to believe??
That the "color cast" of the monitor is dependent on the ambient light in which the monitor is viewed. Just like ambient light is important when trying to match the monitor to the print. Or the Color Checker.
-
Hening
Did you ever got your Eizo calibrated correctly? I am asking this as I was planning to buy the same monitor but not willing to spend 2000 Euros just to face the same problems as with 500 Euros HP monitor. From my experience the the wide gamut ISP panels seem to have this problem. I recently had exactly the same problem with HP 2475 with ISP panel (attached to 24" iMac as a secondary monitor), far too red overall cast, I tried all possible calibrators (I have them all) and spent weeks with it. Finally I tried ColorEeys Display Pro calibration software and that finally solved the problem.
-
(accidental dup cleared, HB)
-
Hi Mikko
I thought I had answered your PM, but now I can not find it. I'll try again here. -
I am now perfectly happy with the Eizo, and I hardly remember the problems I had. I think it all was a failure on my side, comparing to a Samsung whose profile turned out to be corrupted. Also, part of it may have been as ddk wrote, the reddish cast went away by itself after a little while. - The profiling software that comes with the monitor works just fine.
Good light! - Hening.