Calibrate w. i1Display new iMac and new LG Ultrafine to match

[KirbyKrieger]

I haven't been able to get a new 27" iMac and a new 27" LG Ultrafine monitor to match after calibration.  I purchased the iMac and the LG in order to have matched monitors.

I'd like to confirm that my choices during calibration are not causing any issues.  In fact, I'd like to know what steps I can take to end up with matching monitors.

I have calibrated the monitors twice, each time after being on for at least 2 hours.  The color on the monitors is not even close (iMac has pinkish grays, LG has greenish grays, &c.).  The LG is connected to the iMac with the included T'bolt cable.  The screens do not appear to be showing the influence of any external electronic distortion.

The i1Display software — i1Profiler — lets me set or select the following.  Since the monitor in the iMac is identical to the LG (per Apple), I have used the exact same settings for both the iMac and the LG.

Display Type:  G8-LED (this was the default for the iMac)
White Point:  CIE Illuminant D65
Luminance:  Custom - 85 cd/m^2  (I have always preferred luminance in the 80-90 range.  I am calibrating in order to pre-proof prints.)
Tone Response Curve: Standard
Gamma:  2.20
Ambient Light Smart Control:  Off
Automatic Display Control:  (Have used both "On" and "Off".)

Additionally, I have set the iMac Display Preferences to not vary the luminance.  The ghastly "Night Shift" is off.

To my eye, the luminance of the displays is matched (at least in the mid-tones, which is all I've checked so far).  The other aspects of color, particularly hue, are wildly divergent.

As a personal and meta Q: how can it be so damn hard to get matching monitors?

Thanks.

[digitaldog]

It's possible, due to differences in the two, that you'll never get a close match.
It's VERY possible you'll need vastly different calibration settings to get close: trial and error.
Getting luminance nailed first was a good move! Now work on color (white point and IF possible, and probably necessary, control over the green/magenta axis).

[smthopr]

I haven't been able to get a new 27" iMac and a new 27" LG Ultrafine monitor to match after calibration.  I purchased the iMac and the LG in order to have matched monitors.

I'd like to confirm that my choices during calibration are not causing any issues.  In fact, I'd like to know what steps I can take to end up with matching monitors.

I have calibrated the monitors twice, each time after being on for at least 2 hours.  The color on the monitors is not even close (iMac has pinkish grays, LG has greenish grays, &c.).  The LG is connected to the iMac with the included T'bolt cable.  The screens do not appear to be showing the influence of any external electronic distortion.

The i1Display software — i1Profiler — lets me set or select the following.  Since the monitor in the iMac is identical to the LG (per Apple), I have used the exact same settings for both the iMac and the LG.

Display Type:  G8-LED (this was the default for the iMac)
White Point:  CIE Illuminant D65
Luminance:  Custom - 85 cd/m^2  (I have always preferred luminance in the 80-90 range.  I am calibrating in order to pre-proof prints.)
Tone Response Curve: Standard
Gamma:  2.20
Ambient Light Smart Control:  Off
Automatic Display Control:  (Have used both "On" and "Off".)

Additionally, I have set the iMac Display Preferences to not vary the luminance.  The ghastly "Night Shift" is off.

To my eye, the luminance of the displays is matched (at least in the mid-tones, which is all I've checked so far).  The other aspects of color, particularly hue, are wildly divergent.

As a personal and meta Q: how can it be so damn hard to get matching monitors?

Thanks.

Maybe it's your display type setting.  Try some others like ""RG Phosphor" and "GB-LED" and see if you can get better results.