different readings from two monitors

[photesh SourceForge]

Hi,
I have two monitors and colormunki device.
I’ve spent days trying to fitgure out why after calibration(with no profiling, or with) of both montiors with exactly same settings I have one monitor pinki-red at white, while another is cyan -green.
The only answer could be instrument has different reading.

The panels are not perfect, and not uniform, so made a test:
I’ve calibrated values(Lum, x,y) as close as possible with manual (interactive) calibration only.
I can see that one is pink and another is cyan a little.
I’ve opened monitor test (white screen) and covered monitors so I could se as much as reading device.
These open parts are close one to another so my eye is not tweaked in the darkroom.
I could see the difference. And switching device from one to another monitor, for given same luminance i had same values (x,y) for the target white point.
I’ve removed device and calibrated visible parts with eye – it seems more precise in this case.
So I have to pretty equal whites, but readings are different with the same munki device on two monitors with the same luminance.

How is it possible ? What can I do ?
What would be the use of calibration when I can’t be sure about values obtained from the device 😉

Thank You,
Tim

[Florian Höch]

Hi, what’s your exact instrument (there are multiple devices under the ColorMunki brand)?

[photesh SourceForge]

Hi,

Hi, what’s your exact instrument (there are multiple devices under the ColorMunki brand)?

Colormunki Smile (x-rite)

• This reply was modified on 2015-10-22 19:16:13 by photesh.

[Florian Höch]

What types of displays are you calibrating? I’m especially interested in the type of backlight as the Smile has tables for CCFL and white LED (selectable under measurement mode).

[photesh SourceForge]

>What types of displays are you calibrating?
>I’m especially interested in the type of backlight
>as the Smile has tables for CCFL and white LED
> (selectable under measurement mode).

Dell U2412M
LG 24MB65
I was using White Led mode for both, technically the same options for both monitors.

—
I was trying to figure out how Argyll works, and found spot metering tool(spotread).
Running the tool, in the RBG numbers I can see somewhat close what my eye see.

When I set both monitors visually same white,
spot meter shows pretty the same numbers for both monitors.

When I was using dispcalGUI interface, I could see sliders and two colour numbers and one number for luminance.
The numbers are different for monitors, when I have visually same colors for both monitors.

—

I think, i should be able to setup white point with spot metering tool.
RGB values are good, cause monitor has RGB controls for manual calibration.
it is not user friendly like tool in the dispcalGUI, but i can try.
than can try to use dispcalGUI with “AsMeasured” white point. That I can try tomorrow.
the only conern if there some different (i.e. Lab) map is used in the rest of calibration that caused that hue shift between monitors. will see.

If You have any other ideas, please let me know.
Also I am open for any experiments/tests.

• This reply was modified on 2015-10-22 21:56:29 by photesh.

[Florian Höch]

I was using White Led mode for both, technically the same options for both monitors.

Yes, that should be fine.

I was trying to figure out how Argyll works, and found spot metering tool(spotread).
Running the tool, in the RBG numbers I can see somewhat close what my eye see.

spotread doesn’t report RGB though, it reports in XYZ.

The numbers are different for monitors, when I have visually same colors for both monitors.

I would just ignore the bars and use the setting that gives you a visual white point match. This requires setting the whitepoint to “As measured”.

[buckiejoe SourceForge]

Try tilting your device up or down while doing a run and try using different parts of the screen for measuring, corners and sides perhaps.

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