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I was trying to calibrate an LCD TV this weekend using DisplayCAL and i1Display Pro(NEC OEM).
TV is connected to a PC and DisplayCAL was running there. Ran into the issue where adjusting settings on the TV had no effect on the levels of the colors during the initial calibration phase. I figured there was nothing that could be done about that and proceeded to create a profile.
After the profile completed there was a small change in image quality when using the “preview” checkbox. After the profile, I ran the calibration step again and to my surprise the levels of the colors had not moved or moved so slightly that I couldn’t see a difference(I took a before picture to be sure).
My question then is related to this. Am I misunderstanding what DisplayCAL does? Does the Profile phase not create a profile that compensates for the color variances? Shouldn’t profiling in theory create a profile that would have made all the colors aligned to the center?
The colors on the TV are noticeably not accurate. The reds especially are way too intense(the colorimeter noticed this as well). It should also be noted that I have also used this on my PC monitor before and small adjustments to the monitor resulted in immediate changes in the reading during the calibration phase. But with the TV I could change setting from min to max and there would be hardly any difference in the readings.(even though the colors were very obviously different on the TV)
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Disclosure: As an Amazon Associate I earn from qualifying purchases.TV is connected to a PC and DisplayCAL was running there. Ran into the issue where adjusting settings on the TV had no effect on the levels of the colors during the initial calibration phase.
You are clipping one (or several) of the channels, which is a very bad thing to do – none of the channels should clip. If increasing one channel doesn’t change the readout anymore, then you should reduce that channel until it no longer clips and then decrease the other channels instead of trying to increase the previously clipping channel.
My question then is related to this. Am I misunderstanding what DisplayCAL does?
Yes. During interactive display adjustment, no calibration is active, otherwise it would be very hard to adjust the display (you could never be quite certain what effect is coming from any previous calibration and what is coming from adjusting the display controls).
Does the Profile phase not create a profile that compensates for the color variances?
No, you need to use ICC color managed applications, the profile on its own will do nothing. The only global effect you’ll see is the 1D calibration (adjustment) being applied via the video card gamma tables.
Shouldn’t profiling in theory create a profile that would have made all the colors aligned to the center?
No, see above.
If you want to check the calibration and profile after it has been created, you should use the verification feature and create a measurement report.
In your case, the clipping channels have already degraded the result, so you need to start over.
I am unable to try again at the moment as it was at a friends house and his TV, but for my understanding, please bare with me.
Clipping: I will have to look into this a bit more. Initially the TV didn’t have individual color controls. We would adjust things such as “color” and “tint” in the settings and this would result in obviously different colors on the screen, but no difference in the readings. We then later accessed the service menu and cautiously adjusted those setting. We were unable to alter the image of the screen from there, but that is probably more to do with our misunderstanding of how that menu works. But as I said, we had adjusted setting from min to max and saw no difference.(Edit: If I recall correctly we even adjusted it so the colors were black/white and still calibration measurement was unaffected)
Interactive Display Adjustment: What you say is interesting if I am understanding it correctly. When I run the calibrator, you are saying that the ICC profiles are disabled? If so, that is good. I had previously been removing the ICC profiles before calibration so as to not be calibrating on an already calibrated monitor. Out of curiosity, is that why when I start up DisplayCAL that the screen will flicker? Is that it removing the profile?
ICC: I am still confused about this. I calibrate, then profile, then install that profile. If I do nothing else, then I will only get the benefit of the 1D calibration? Would this not affect the window’s desktop? We didn’t open up any applications, instead we just looked at the desktop icons and could clearly see, especially in the reds, an over intensity. By color managed applications, would something like PhotoShop be an example? Would it have a setting somewhere to select a profile to use?
When you say a profile shouldn’t align the colors, and say to “see above”, are you referring to your reply for how DisplayCAL removes profiles during Calibration?
I’m sorry to say that I am completely uneducated with regards to these matters. So I am sorry if I sound, well, like I am completely uneducated in these matters.
(Edit: If I recall correctly we even adjusted it so the colors were black/white and still calibration measurement was unaffected)
That’s not possible until there are currently not any measurements running or the instrument is broken. A visible change on screen (for the single currently measured color patch, not overall!) will definitely effect a change in the readout. But if a channel is clipping, a white color patch will not change when increasing that channel, because all channels are already maxed – some things around it may change, depending on what else is on screen, as it’s likely not all white.
*EDIT* for a simple “color” or “tint” control, it is true that removing all color may not change the readout of an R=G=B value – it’s already neutral in terms of RGB balance (but not necessarily in terms of actual visual impression). You need access to the actual per-channel R G B gains to be able to adjust neutrals.
Interactive Display Adjustment: What you say is interesting if I am understanding it correctly. When I run the calibrator, you are saying that the ICC profiles are disabled?
There is no such thing as an ICC profile being enabled or disabled. Applications have to actively support and opt-in to use ICC profiles, and the vast majority of them don’t, typically only a few image viewers and graphics applications may have the capability.
I had previously been removing the ICC profiles before calibration so as to not be calibrating on an already calibrated monitor.
That’s not needed. Any existing calibration is automatically disabled during the interactive display adjustment and calibration measurements.
Out of curiosity, is that why when I start up DisplayCAL that the screen will flicker?
No, it is checking if it can access and successfully change the video card gamma tables, which is a prerequisite for calibration.
ICC: I am still confused about this. I calibrate, then profile, then install that profile. If I do nothing else, then I will only get the benefit of the 1D calibration? Would this not affect the window’s desktop?
Correct, yes.
By color managed applications, would something like PhotoShop be an example?
Yes.
Would it have a setting somewhere to select a profile to use?
It will use the display profile assigned to the respective display in Windows color management settings (or the profile associations dialog of the DisplayCAL profile loader, which is equivalent).
I’m sorry to say that I am completely uneducated with regards to these matters. So I am sorry if I sound, well, like I am completely uneducated in these matters.
Don’t worry, don’t be sorry 🙂 Everybody starts somewhere.
