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I’m a photographer, and have been calibrating my two monitors for many years. I shoot RAW 16-bit images and make all my corrections in Adobe Lightroom. My published work is sRGB JPG. What I want is for my monitors to be calibrated for accurate sRGB.
I just tried DisplayCAL this week but after a few attempts (and several hours) I’m not getting the expected results. Using a gray chart, in the light areas near white a color cast is clearly visible. One on monitor it’s green, and on the other it’s red. Also overall contrast is different on the two monitors.
Using the builtin app that came with my colorimeter, I get a slightly better result. Still, I can see a slight color cast. That’s why I’m trying DisplayCAL but I’m not getting rid of the color cast. If anything, I’m not even getting as good of a result using the 5 minute calibration app that came with the colorimeter. DisplayCAL is taking over a hour.
There must be something I’m missing. Here’s what I’ve tried.
- Reset monitors to factory settings
- Use default settings of DisplayCAL (advanced options disabled)
- Selected Spyder4 as my instrument
- Mode is LCD (tried both generic and white LED)
- Correction Auto/None
- White and Black Drift were not enabled
- Run the calibration test and then set the R G B values manually on the monitor.
Attempting to set the monitor’s RGB values would cause brightness to drop. Increasing brightness would only cause the already too high color value to increase. Eventually I get the RGB colors to balance even if the brightness was below the target.
Wait an hour, and I get a color cast using the generated profile. Each monitor has a different color cast.
Without knowing much about what I’m doing, I ran the Measurement Report. The summary listed everything as “not ok.” Looking at the overview, values are in the green until I get to #38-#40. There they jump to a delta of 3.06 and even 4.21. This seems to be what I see, where the brighter grays get a color cast.
Looking at the Gamma chart, values at 80% start falling off and turn from green to yellow and red. Values above 85% are below 2.0.
RGB Gray Balance shows an equal drift starting at 87%. The three colors separate before finally rejoining at 100%.
What settings DisplayCAL should I be using? What’s the procedure I should be following?
- Mac OS 10.12.6
- AMD Radeon R9 280X video card
- Two ViewSonic VP2365LED monitors (LCD with LED backlight, but I don’t know if it’s white or RGB but I suspect it’s white)
- Spyder4 Pro
- DisplayCAL 3.3.5.0
This might be helpful.
14:39:37,227 Report on uncalibrated display device
14:39:38,904 ——————————————————————————–
14:39:38,905 Command line:
14:39:38,905 /Applications/DisplayCAL/Argyll_V1.9.2/bin/dispcal
14:39:38,906 -v2
14:39:38,906 -d2
14:39:38,906 -c1
14:39:38,907 -yn
14:39:38,907 -P0.5,0.5,50.0
14:39:38,907 -R
14:39:38,907
14:39:38,916 DisplayCAL: Starting interaction with subprocess
14:39:39,273 Setting up the instrument
14:39:41,491 Instrument Type: Datacolor Spyder4
14:39:41,491 Serial Number: 05230458
14:39:41,492 Hardware version: 0x070f
14:39:41,800 Place instrument on test window.
14:39:41,802 DisplayCAL: Waiting for send buffer
14:39:43,304 DisplayCAL: Skipping place instrument on screen message…
14:39:43,309 DisplayCAL: Sending buffer: ‘ ‘
14:39:43,365 Hit Esc or Q to give up, any other key to continue:
14:40:08,463 Patch 3 of 3
14:40:57,080 Patch 17 of 17
14:41:45,618 Patch 17 of 17
14:41:45,619 Uncalibrated response:
14:41:45,619 Black level = 0.2479 cd/m^2
14:41:45,620 50% level = 26.02 cd/m^2
14:41:45,620 White level = 135.14 cd/m^2
14:41:45,620 Aprox. gamma = 2.38
14:41:45,621 Contrast ratio = 545:1
14:41:45,621 White chromaticity coordinates 0.3122, 0.3414
14:41:45,621 White Correlated Color Temperature = 6443K, DE 2K to locus = 11.5
14:41:45,622 White Correlated Daylight Temperature = 6440K, DE 2K to locus = 8.4
14:41:45,622 White Visual Color Temperature = 6024K, DE 2K to locus = 11.1
14:41:45,623 White Visual Daylight Temperature = 6157K, DE 2K to locus = 8.1
14:41:45,623 dispcal: Warning – Unable to determine effective Video LUT entry bit depth
14:41:45,625 The instrument can be removed from the screen.
14:41:45,631 DisplayCAL: Reached EOF (OK)
If you’re going to match two monitors to one another, use the same whitepoint target (not “As measured”) on the calibration tab. Note that most “standard” (= roughly sRGB) gamut LCD displays use white LED backlighting. Also see the FAQ re visual whitepoint matching in case the monitors are different models and/or use different backlighting technologies.
Thank you Florian. Yes, I’ve read those articles. My question is how to get rid of the color cast. Set aside for the moment that I have two monitors I wish to match. Each one individually isn’t getting calibrated correctly. There is a clear color cast after building the profile with DisplayCAL. This is less of a problem with the Spyder4 software. I’m sure DisplayCAL can produce a better calibration than that.
Why am I getting a poor calibration using DisplayCAL?
Each one individually isn’t getting calibrated correctly.
Compared to what? There is no “absolute” white reference with respect to how the human visual system works. Color casts are always perceived in comparison to something else, be it ambient lighting or another source of “white” light that is bright enough to influence adaptation state.
There is a clear color cast after building the profile with DisplayCAL. This is less of a problem with the Spyder4 software.
This to me is an indicator that you may not be using the same settings in both softwares, especially whitepoint.
The monitor itself displays a color cast. I have a test pattern of several gray squares. The darker 80% are good. The lighter 20% have a color cast. I think the reports I included show this. The lighter values of grey are not neutral.
When I re-calibrate with Spyder4, it’s improved. It’s not accurate but has less of a color cast.
I’m certain DisplayCAL can do a much better job of calibrating than the Spyder4 software. I’m not able to get that. I’ve tried several different settings, but I’m not getting better results.
The Spyder4 software recommends a white point of 6500k. It can be changed to native. It also has the option of using the monitors RGB adjustments, but recommends against that.
I think my question is based on not understanding how to use the DisplayCAL software. The lighter 20% of a grey scale is showing a color cast. How to I correct for this?
This sounds a bit like the monitor is driven with wrong levels by the graphics card. Attach the profile please (“Create compressed archive…”).
Attach the profile please (“Create compressed archive…”).
I’m not sure what you’re asking. How do I create the “profile” you need?
I found a way to look at the curves after calibrating. I zoomed into the upper RGB values. Looking at the attached I see how the three channels have drifted apart.
This portion of the RGB curves seems to be what I see (what I’ve been calling the color cast at upper levels).
I’m not sure what you’re asking. How do I create the “profile” you need?
You already have it. The “create compressed archive…” button is next to “Settings” with the profile selected.
This portion of the RGB curves seems to be what I see
Nothing out of the ordinary.
OK, now I understand what you are asking for. I’m not familiar with the software, so you’ll have to forgive me.
I’ve attached a couple profiles I’ve tried for both of my monitors. Seems like it’s the green that I can’t get correct, at least that’s what my eyes are showing me.
OK, now I understand what you are asking for. I’m not familiar with the software, so you’ll have to forgive me.
Don’t worry about it, I don’t expect anyone to instantly know the ins and outs of admittedly relatively complex software.
I’ve attached a couple profiles I’ve tried for both of my monitors. Seems like it’s the green that I can’t get correct, at least that’s what my eyes are showing me.
Try decreasing calibration speed to “medium”.
I’m still testing different settings, but haven’t found one that changes the results. I still get a green cast on one monitor.
I have a test image (set of grey blocks going from black to white on one row, and white to black on the bottom row). I can enlarge this image to span across both monitors. I notice the Mac will alter the image based on which monitor contains the most amount of pixels for the image. I can center the image across the two monitors and move it slightly left/right to see the image colors change. I’m not suggesting there’s something wrong with this. I’m only describing this since I noticed it.
Still, the gray blocks on just one monitor shows a color cast in the brighter areas. One monitor becomes green, and the other becomes red.
Also, I found a new problem happening after changing the quality and calibration speed. After completing the calibration, DisplayCAL moves on to “create profile from measurement data.” This step usually happens in less than a minute. But half the time this took over 10 minutes. I also get the spinning beachball, and the normally continuous sound that plays breaks up. It plays for a few seconds, then stops for a few seconds, and repeats like this. First time this happen I forced quit the app thinking it was basically crashed or hung. When it happened again, I let it alone until it finally finished. The third time I happened while I was waiting, and kept track of how long it took – over 10 minutes.
Just completed another attempt at calibrating. To give you an idea of just how green the gray chart is, during the display adjustment phase to get the target white point I have the monitor set to red at 97, green at 100, and blue at 99.
After calibration, to get rid of the green cast and get neutral greys I have to turn the green down to 75. Even the second monitor is showing the green cast, and to get it neutral I have to bring the monitor’s green down from 93 to 82.
Something is really off but I don’t know how to fix it. Maybe setting the white point isn’t working?
I don’t have this problem with the included Spyder4 software. After calibrating with DisplayCAL, how do I verify what my eyes are clearly showing me?
Still, the gray blocks on just one monitor shows a color cast in the brighter areas. One monitor becomes green, and the other becomes red.
This is a common problem in matching displays, see the FAQ on visual whitepoint mismatch.
DisplayCAL moves on to “create profile from measurement data.” This step usually happens in less than a minute. But half the time this took over 10 minutes.
Is the machine starved for RAM? If swapping to disk occurs, things usually slow to a crawl. This is not a problem per se.
My system has 32GB of RAM. VM isn’t thrashing to disk with any other apps, including big memory useage like Lightroom. DisplayCAL didn’t have this problem until I changed the quality and speed settings.
Again, I’m not comparing the two monitors. I’m not talking about trying to match two monitors. I read all the docs, three times so far. I read the FAQ and the one about trying to match two monitors. I’m aware of human color perception issues.
I’m seeing green on the monitor. I can turn off the second monitor, and the remaining one is clearly green. The test image of grey blocks on one monitor become green – so green it’s obvious. The latest calibration of the other monitor has made it green too. So both have become green.
The light grey blocks are green, not grey. I can hold up a physical grey card and the monitors are green. My eye’s color perceptions are good. I’m a photographer, and I’ve had my eyes checked for color. I assure you, the monitor is very green after DisplayCAL creates a profile.
I recalibrate with the Spyder4 software, and there is no green cast.
Something isn’t working when I try using DisplayCAL. I don’t understand what’s going wrong or how to fix it.
