Calibration using DisplayCal and UltraStudio Mini Monitor

I’m calibrating an external monitor which is an LG, connected to an Apple iMac Pro using the UltraStudio Mini Monitor. I am using the DisplayCal software. The iMac is my workspace and the external monitor is for reference. I’m using the DisplayCal software to calibrate the LG via the Calman integration in Resolve which actually works with DisplayCal. Hence DisplayCal is using the test patterns from Resolve. When calibrating, the colors of the patches on Resolve that is displayed on the iMac 5K Retina display is much more saturated that what is shown on the LG monitor. Granted that the iMac Display is set to default to Apple’s Display P3 and the LG is being calibrated for Rec709 Gamma 2.2, is this okay or is there something wrong? When I run the measurement of the LG before calibration, everything was at or very close to the target white point. My colorimeter is the x-rite i1 Display.

Display during Calibration…

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Display after Calibration…

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Since I have a very similar setup and don't see that much of a difference, I'll have another look at the settings when I'm back to my grading station.
Currently about 10.000km away from it, but we'll fly back on Monday.

I hope someone else is going to chime in.

I find that the image on the LG monitor after calibrating had more dynamic range to grade with and as I played around with grading the image, I felt that it gave me the flexibility to get the look I wanted, albeit that the colors and brightness on the viewer of Resolve on the iMac was terribly saturated and dark. Here is a screenshot from the resulting h.264 that was rendered and sent to my IPad for viewing.

Do note that this is a screenshot and a small jpeg file so it can be uploaded here.

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Since I have a very similar setup and don't see that much of a difference,

Uli, just trying to understand your statement… Did you mean that you’re not seeing much difference between your iMac and external LG, or that you don’t see much difference with your displaying to what’s shown here. Thanks much!

I meant that I don't see that much of a difference between my iMac and the calibrated LG (soon a Xiaomi).

I meant that I don't see that much of a difference between my iMac and the calibrated LG (soon a Xiaomi).

That’s very curious. I wonder what I’m doing wrong with my calibration settings.

Sorry, can't compare right now, since I don't remember my settings on that iMac.
I'm going to set up a new station based on a Mac mini M4 Pro, 4K cards by BM and my recently repaired Asus ProArt. The Xiaomi (curved wide) will be my editing monitor. Yaiii

Anyone there who has similar setup please chime in…. Just curious if your calibrated monitor looks far off from your editing monitor.

Recalibrated the monitor this time setting DisplayCal to Rec709 1886 at 100 cd/m2, and set the lighting of the room to < 5 lux measurements. Results are better but still distinguishable between the iMac which is the editing display (left) and the LG being the calibrated LG display (right). The iMac has it defaulted to Display-P3 and the LG being calibrated for Rec709.

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Here’s an image (with no grading at all) comparing the iMac Retina 5K display with the LG after calibration.

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Do note that these are pictures taken of the monitor and compressed so it can be uploaded and attached here so the rendition is not as good.

I’m wondering if the brightness needs to be at about 80 cd/m2. But that’s could be too low for SDR.

Also the Mini Monitor only outputs at 1080 (HD) and the display of the LG is a VA. I’m questioning since the mini monitor is bypassing the Mac’s color management system, the color and luminance is more representative of what Resolve is sending as broadcast accurate - yes? - hence the difference in the color and saturation.

It's at least partially due to different screen technology. 100 to 120 nit should be right for SDR.
But since you use Display Cal anyway, why not try to calibrate the iMac too? DisplayCal can generate a LUT, which you need for proper I/O with a BM device.
But it can also generate and load an ICC into the Mac, aiming for Rec. 709, of course. That should get you pretty close, if using iMac settings for viewers. The rest is backlight technology.

All your answers will be in the post calibration report. What does it say?

Don’t be surprised if your GUI you’ve been staring at is off.

All your answers will be in the post calibration report. What does it say?

Don’t be surprised if your GUI you’ve been staring at is off.

So here's the data from the LG monitor measurement and it's not a perfect monitor like the $15K Sony BVMs but for Rec709 1886 I think this will do for me.

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I'm somewhat lazy to go and analyze the measurements one for one so I usher the assistance of ChatGPT, however I made sure that I verified its analysis and responses. Golly, it dd a good job!

Given the above measurements I asked it rate the monitor for Rec709 1886 color monitoring (in a nutshell... my prompt was much more thorough). Here's what it answered:

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Then I asked for what's deficient with the monitor based on the measurement report and here's what it answered and I think I can live with that... Delta < 2 which most prosumers monitors are reported to be.

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I'm looking into the Asus ProArt series so that's in my list.

Those commentaries seem quite accurate to me.
I'll post the values for my recently repaired (actually replaced) Asus ProArt soon.

Those commentaries seem quite accurate to me.

I’m contented with it too.
I’m going to calibrate the iMac for similar colorspace, white point, and gamma as what I used for the LG. I’ll see if the displays will match closer to each other when I use the generated and installed ICC.

If that has never been done before, it should definitely help to get them closer.

Just calibrated the iMac with same settings as the LG. It looks closer. I think the difference is that the iMac is backlit. iMac is viewer left, LG is right. Keep in mind these are compressed photos of the screens so it’s not fully representative… . It’s definitely matching better than previous.

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