I recently tried measuring both a new Westinghouse VR-3730 LCD HDTV and my older Panasonic 42PZ85 plasma HDTV. I used my i1 Display LT colorimeter with HCFR software, only to find a large RED color shift. The subective PQ looks OK but the i1 is reading RED at about 50-60% lower than what I would be expecting.
I directly compared an older data file of my Panasonic TV with a new one at the same TV settings. The luminance and gamma charts are quite similar but the RGB levels, color temperature and CIE diagrams are different or shifted, especially WRT red values.
Is this magnitude of drift error that others have experienced with i1Display colorimeters? Or is there something else that is the problem?
Can HCFR software null this error out? Is this feature within it's capabilities?
Quote:
Originally Posted by Plasma54321 /forum/post/21934749
So if I understand what you are saying, the grayscale measurement only consists of the GREEN or Y component (of the XYZ system), therefore my OLD and NEW plots for luminace and gamma are similar.
Then, why when adjusting the white point, one balances all 3 colors to 100% as the goal, the colorimeter must read the RED and BLUE colors to allow this adjustment? I'm not getting it. Why some of my charts are similar and some are not? It seems like they should all be out of whack.
The Y value is luminance, so if the Y filter didn't change much, then luminance response would measure similarly given the that the display is still similiar to when you measured it originally.
Color is the ratio of X to Y to Z. So if the X filter is off, then it will change the ratio so you'll get an entirely different color reported back than you are measuring.
Quote:
Originally Posted by airscapes /forum/post/21934278
He is in the anger phase.. has not accepted the loss yet.. but it in reality, what is done is done and no amount of crying will fix the problem.. time to get back on the horse and move on!
I think my I1D2 has drifted too, only had it for a week. Couldn't find driver on Xrite site, it's discontinue. When I do my CMS calibration, it's shows my red and blue are under saturated. Crank up blue and red to 100 and still not working.
Quote:
Originally Posted by kanti123 /forum/post/21947157
I think my I1D2 has drifted too, only had it for a week. Couldn't find driver on Xrite site, it's discontinue. When I do my CMS calibration, it's shows my red and blue are under saturated. Crank up blue and red to 100 and still not working.
I suspect your issue is not drift but rather initial accuracy. You may be able to live with the grayscale errors this meter leaves behind, but the gamut errors are harder to ignore.
Also, if your primaries start out undersaturated in custom color space at defaults, then nothing with move them outward (increase saturation). If the latter is the case, then you don't have a meter issue.
I just re-measured my Panasonic plasma and compared the measurements to ones I took in May 2012 (5 months ago). My Display Lt is reading blue higher than it did in May, so my red hasn't drifted but in fact my blue has. My blue readings back in May were all in line with red and green across the grayscale and now the blue readings are about 110% across the grayscale, i.e. my color temp has gone from 6500K to about 7250K.
Could my TV set have drifted or is it more likely that my Display Lt has drifted? If the latter, then can I use my TV set as a reference and create a manual correction matrix for use in HCFR?
Quote:
Originally Posted by daMaster /t/1406079/massive-color-drift-correction-for-i1-display-colorimeter/60#post_22479473
Could my TV set have drifted or is it more likely that my Display Lt has drifted? If the latter, then can I use my TV set as a reference and create a manual correction matrix for use in HCFR?
Quote:
Originally Posted by daMaster /t/1406079/massive-color-drift-correction-for-i1-display-colorimeter/60#post_22479473
I just re-measured my Panasonic plasma and compared the measurements to ones I took in May 2012 (5 months ago). My Display Lt is reading blue higher than it did in May, so my red hasn't drifted but in fact my blue has. My blue readings back in May were all in line with red and green across the grayscale and now the blue readings are about 110% across the grayscale, i.e. my color temp has gone from 6500K to about 7250K.
Could my TV set have drifted or is it more likely that my Display Lt has drifted? If the latter, then can I use my TV set as a reference and create a manual correction matrix for use in HCFR?
The TV may have drifted, but more likely the i1 meter did. They are known for drift with age due to deterioration of the color filters. You can buy an i1 Pro spectrometer to "profile" or correct the errors in your i1 Display colorimeter, but you will have to do that periodically since the meter will continue to drift.
In other works, you have to buy or rent a meter to make sure your i1 Display is close to accurate. Or buy another meter which still may drift. These are well known issues with hobbyist grade meters unfortunately.
Recalibration is one thing, deterioration is another.
Quote:
Originally Posted by Phase700B /t/1406079/massive-color-drift-correction-for-i1-display-colorimeter/60#post_22479844
In other works, you have to buy or rent a meter to make sure your i1 Display is close to accurate. Or buy another meter which still may drift. These are well known issues with hobbyist grade meters unfortunately.
That makes sense but it does open up another question, and that is how often should the instruments be re-calibrated? I know there isn't any black and white answer for that because all meters are different from consumer grade (hobbyist) to professional. It seems to me that unless the user has a perceived change in the performance of their tv (real or imaginary), then re-checking the calibration shouldn't be done unless they have recently re-calibrated their meter, period. Otherwise, issues like this come up and you don't know if the problem lies with the tv or the meter(s), and you can spend a lot of time chasing your tail. For a lot of us (some of us more OCD than others
), checking and tweaking is a hard habit to break and that can be very disconcerting if the meters aren't kept in perfect (or as close as is possible) condition, which can be costly. Sort of like the dark side of calibrations. I almost wish I hadn't started the slippery slope of calibrating (I know, I can hear the groans and the hands slapping foreheads now) but then I look at my pq.....................
Quote:
Originally Posted by Otto Pylot /t/1406079/massive-color-drift-correction-for-i1-display-colorimeter/60#post_22483840
That makes sense but it does open up another question, and that is how often should the instruments be re-calibrated? I know there isn't any black and white answer for that because all meters are different from consumer grade (hobbyist) to professional. It seems to me that unless the user has a perceived change in the performance of their tv (real or imaginary), then re-checking the calibration shouldn't be done unless they have recently re-calibrated their meter, period. Otherwise, issues like this come up and you don't know if the problem lies with the tv or the meter(s), and you can spend a lot of time chasing your tail. For a lot of us (some of us more OCD than others
), checking and tweaking is a hard habit to break and that can be very disconcerting if the meters aren't kept in perfect (or as close as is possible) condition, which can be costly. Sort of like the dark side of calibrations. I almost wish I hadn't started the slippery slope of calibrating (I know, I can hear the groans and the hands slapping foreheads now) but then I look at my pq.....................
NIST certification is only good for 1yr, so you can see where NIST must think the meters don't drift enough until after a year to invalidate their calibration results.
Granted all meters are designed differently so they will all age differently, but nobody is getting meters re-calibrated on anything shorter than 1yr increments. That said the amount of drift you see in a high end meter like a K-10, Jet 1211 or even a i1 Pro is pretty small at 1yr and with the i1 Pros we see some of them coming in 3 and 4 years out that are still within factory specs.
It shows the clear reason why pros have to purchase higher quality to minimise design limitations.
I spoke directly with Jeti about NIST regarding my jeti1211, pretty concluded with the calibration is more of a check and a NIST resert on a yearly basis, the actual change or drift with the device is typically only as much as the design deviation.
Quote:
Originally Posted by sotti /t/1406079/massive-color-drift-correction-for-i1-display-colorimeter/60#post_22484405
NIST certification is only good for 1yr, so you can see where NIST must think the meters don't drift enough until after a year to invalidate their calibration results.
Granted all meters are designed differently so they will all age differently, but nobody is getting meters re-calibrated on anything shorter than 1yr increments. That said the amount of drift you see in a high end meter like a K-10, Jet 1211 or even a i1 Pro is pretty small at 1yr and with the i1 Pros we see some of them coming in 3 and 4 years out that are still within factory specs.
Can the i1Pro's be re-calibrated (not just re-certified) if you send it to X-Rite directly? Has anyone ever needed to do this, given that you see units 3-4 years past the expiration of NIST certification that are still within spec?
What does SpectraCal do when you send in the i1Pro to them?
Basically, for a DIY user who owns a i1Pro that is outside of NIST certification, do they need to worry about re-calibration? If so, at what point (how many years since the last NIST Cert)?
So, if someone sends in a i1pro for re-cert to SpectraCal and it is out of spec (unlikely but let's assume it is), do they still get charged $175 for the re-cert? I ask because I assume the re-cert would then be pointless if the meter was out of spec and the owner would have to spend another several hundred dollars for the re-cal in Switzerland.
Also, do you update the LED tables during a re-cert (assuming the meter is in spec)?
Thank you Joel for sharing this. I think a lot of folks who are new to the DIY aspect of calibrating don't have a clear understanding of the differences between certification and calibration, and what they mean quality-wise and cost-wise. Good questions PlasmaPZ80U!
The verification service is only for certain meters and is basically only a pass fail test.
For the i1 Pro the only service available would be the Recertification service. That would include getting the enhanced LED table added or updated as well.
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