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Hi! As you know, I have being going back and forth with a colleague that have the same hardware, but we have different colorimeters / spectrometers.
With the screen at 100% brightness, and no calibration loaded, I was getting a contrast ratio of 1070:1 with the Colormunki with a minimum black point of about .15 and he was getting with his Spyder 5 a contrast ration of about 750:1 with a minimum black point of about .45 so then I tried my Spyder 4 and I also got a contrast ratio of about 730:1 with a min black point of .4xxx
So the question, who should I believe? Colormunki or Spyder??? Is there a way to find out if the Colormunki black reading is accurate? Like test it several times and see if I always get the same? would that help to see if the device can be trusted on its black reading?
Also, you mentioned several times the Spyder can be calibrated with the use of the Colormunki, could you give me a quick explanation of how to do that? or point me to the documentation where that is explained? I remember seen something but now I can’t find it.
Would that calibration affect only the color readings or will affect also the black reading too? I know this particular screen has a pretty new technology of backlight and Spyder might not have the right correction profile
Hey!
So im the one with the 750:1 reading for the same type of panel when using the Spyder 5.
Other than what Victor stated above, when i do a 256 Gray Testchart verification, even if i have all of my profiles unloaded, DisplayCal changes to a very cold profile.
I made sure Windows Calibration was off, moved all my profile data out of the DisplayCal storage folder.
Im guessing, and i might be completely wrong here, that DisplayCal is loading a correction profile for the Spyder 5?
So the question, who should I believe? Colormunki or Spyder???
I would lean towards the ColorMunki, although spectrometers usually don’t have the best low light accuracy.
Is there a way to find out if the Colormunki black reading is accurate?
If you start a calibration with interactive adjustment enabled, you can move the measurement window out of the way and bring up a black patch (e.g. in MS Paint) instead. Then you can observe if/how much the readings fluctuate.
Also, you mentioned several times the Spyder can be calibrated with the use of the Colormunki, could you give me a quick explanation of how to do that?
With both instruments connected, click the blue “Refresh” arrow on the “Display & instrument” tab so they both show up in the instrument dropdown. Select the Spyder. Next to correction, click the blue “plus” icon. In the window that pops up, click “Measure” for both the ColorMunki and Spyder.
Would that calibration affect only the color readings or will affect also the black reading too?
It’ll affect everything (to some extent also the black level reading), and the correction will also make the Spyder’s white level reading match the ColorMunki’s.
Other than what Victor stated above, when i do a 256 Gray Testchart verification, even if i have all of my profiles unloaded, DisplayCal changes to a very cold profile.
You’re probably just observing the display with linear videoLUTs.
You’re probably just observing the display with linear videoLUTs.
So is that normal ? Is there any way to prevent that from happening? Since it does not happen when Victor uses his Colormunki spectrometer.
And since i do not have a spectrometer like Victor, is there any way for my get the correct contrast values detected and calibrate off of that?
Exactly. When I reset the table, and then I start the verification to see the response of the grayscale on the Uncalibrated monitor I do not see any changes. Or should we create a linear profile in order to do a Uncalibrated verification??
Is there no change when you use the Spyder as well? Or only with the Colormunki there is no change?
Thanks. That was an easy process. And actually applied some correction to the Spyder 4. I’ve uploaded it to the database.
Don’t know yet. Still running the calibration. And Florian will correct me if I’m wrong, but the contrast ratio is a probably a thing to be carefull with using it as a quality indicator. Unless you have a device with NIST (National Institute of Standards and Technology) certificate of accuracy the contrast ratio can be way off. Specially if the error reading comes from the dark portion. An error in reading on the low side of .2 cd/m2 can shave 400 units from a 1000:1 decide, and visually speaking that difference can be something a human will not notice. Different would be a difference in reading of 50 cd/m2 on the top side, that would make that 400 difference something you will really see.
Am I correct Florian?
An error in reading on the low side of .2 cd/m2 can shave 400 units from a 1000:1 decide, and visually speaking that difference can be something a human will not notice.
If you notice the contrast difference or not mainly depends on the viewing conditions (e.g. ambient light level, diffuse light reflecting off the monitor). In a dim environment, the difference may well be very visible, while in broad daylight it could be invisible.
But you agree with me that a difference caused by a .2cd/m2 on black is not as visible as a difference caused by a difference of 40cd/m2 on white? Mathematically speaking they could cause the same contrast ratio difference but is not the same. Kind of like is not the same to have 40% more of 10 million dollars than 40% more of 1 dollar :-))))
No, because a human’s visual system responds to lightness roughly logarithmic, not linear. 🙂
About if calibrating the Spyder with the ColorMunki helped. Yes. It did. Now I got a really nice tint free calibration. Definitely the ColorMunki measures the black darker than then Spyder and repeating the test is consistent, so I think I will believe that the black measures is actually 0.18cd/m2 as I tested about 20 times and got always the same +/- 1 cd/m2.
I keep learning 🙂
Is there any way to share the Spyder 4 correction file? And then using it on the Spyder 5? I do not have access to a ColorMunki Spectrometer.
Now I got a really nice tint free calibration.
That’s great.
Is there any way to share the Spyder 4 correction file? And then using it on the Spyder 5?
Sure, the database is public. This should be the correction file: Spyder4 & AU Optronics B173ZAN01.0 (ColorMunki)
Note though that due to manufacturing tolerances and other variables the correction may not work as well on your particular instrument + display combination (even if it were the same instrument).
You may have to edit the file (replace all occurrences of “Spyder4” with “Spyder5”) in a text editor.
