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Discussion Starter · #1 ·
I've done ISF Day and Night for my SD DVD HDMI input on my 9G and I'm pretty happy with the results. Looks great, checks out very nicely in CalMAN. Red, however, seems to be one area where I'm still having a bit of trouble. I know that the generally accepted method for Red is to use the Color control to hit 21% of the White for output level, but is that still the best way to do it for a 9G?
 

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Greetings


Considering that the TV does not have a functional CMS ... shooting for 21% is a waste of time.


Regards
 

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Quote:
Originally Posted by tonyptony /forum/post/16972542


I've done ISF Day and Night for my SD DVD HDMI input on my 9G and I'm pretty happy with the results. Looks great, checks out very nicely in CalMAN. Red, however, seems to be one area where I'm still having a bit of trouble. I know that the generally accepted method for Red is to use the Color control to hit 21% of the White for output level, but is that still the best way to do it for a 9G?

No, That is NOT the preferred method.


First, as Michael already points out, there is no CMS so you can't target red specifically to do anything about its chromaticity, you can't move it around in xy. The point of targeting a Y% relative to white is a backup way of setting color decoding if the blue filter doesn't work well on the display (if it leaks). First, see whether or not it even leaks, if it doesn't you're wasting your time: just use the blue filter. Check yellow against black, if yellow looks the same as black, it doesn't leak and you're good to go.


If it leaks and you want to use this % method, you need to measure the xy coordinates of each primary and your white point, then plug them into Greg's calculator to compute what that Y% relative to white will be. You CANNOT just plug in 21%, because that presumes that the red you have is actually Rec709 red, which it is not on this display, so that % is NOT correct.
 

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Discussion Starter · #4 ·
Thanks Mike and Chris. Will Greg's calculator give me a different set of target values than the one built into CalMAN?


I have seen a number of reports for calibrated 9Gs in which Red is well within the margin of error for a 21% target, so it seems like it is possible.


I'll just reiterate that I am pleased with my results, but I'm just curious at this point.
 

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Firstly, calibrate your display as close to the Rec. 709 target as possible.


When that is done, switch from the calibration window to the main CalMAN one.


Go to Tools and Editors > Color Target Editor

If you have already done greyscale calibration, uncheck the Lock White xy and CCT option. Leave RGB Y etc. locked.


This will adjust the RGBCMY luminance targets and secondary positions (CMY) to be correct based on your RGB xy values and display's white balance.


Set Level to 75%. Take a reading of 75% white, red, green and bluethis will prompt you to create a name for your new colour target. These readings are saved automatically.


Switch back to the main calibration window and your colour target should have automatically been selected.


If you want to verify this or change the target, go to Options > Grayscale > White Point Target.


This should now be set up to use the correct target luminance values and CMY positions based on your display.



Sounds more complicated than it really is when it's written out like this.
 

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I am finding this thread extremely hard to follow.


First, the poster refers to 9G Kuro, but does not specify whether it is an Elite or Standard (I think it is an Elite). This is important because the Elite is capable of very close to a Rec. 709 gamut. The Standard is not. Thus, if it is an Elite, then 21% of reference white target (to be more accurate, it is 21.3%) is correct.


Second, the 21% target refers to the brightness of the primaries. The Standard has NO CMS and the Elite has a FUBAR CMS. In any case, the presence or absence of a CMS has no bearing on whether this is the correct brightness target. A CMS, even a good one, will only allow you to adjust the color. It won't tell you what the proper target is. Using the standard Color control modestly you can easily achieve this target for any one of the primaries.


Third, filters are not better than direct measurements. Filters can recommend grossly inaccurate settings on some displays, and even when they work the eye is not sensitive enough (especially with blue) to set Color with any precision. Using a blue filter right now, any Color setting between 0 and +4 seems fine. This is 7.5-8.9% for blue and 24.6%-28.3% for red on my 5020. On the other hand, even the inexpensive colorimeters offer quite good accuracy for luminance readings and do better than this.


Fourth, I think that we are exaggerating somewhat how much the luminance targets vary based on primary chromaticity. For example, the 5020 in front of me right now has native primaries of

R: x0.666, y0.325

G: x0.269, y0.654

B: x0.147, y0.059


For those primaries, the correct luminance values are

R: 23.4%

G: 69.1%

B: 7.4%


Blue is almost exactly the same as the nominal Rec. 709 targets and Red and Green vary by only 2% each.


The bottom line? If you have standard primaries, or even close to standard primaries, the fixed luminance targets are fine. If you don't, then the targets may be slightly different.
 

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Discussion Starter · #9 ·
Andrew, thanks for the explanation.


Tom, you are right it is an Elite. And my color actuals are very close to the REC709 targets, as you've said. My original post did not mention CMS as an option for my question (which I had already understood had no bearing on brightness - at least for an Elite), but I do appreciate the discussion regarding CMS anyway. Just was curious as to whether there was something about these models that would suggest any different way to do this. If so I'd plan to try it at my next calibration point (500 hours).
 

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I have a question about the color gamut (Rec. 709) on a Panasonic TC-P50S1. This is only the second HDTV I've ever calibrated (using Chroma 5 and CalMAN) and since my TV (Pioneer Elite Pro-111FD) had a color gamut that very nearly matched Rec 709, I hadn't encountered this before. I've attached a PDF file with a post-calibration report for Standard mode, although all the other modes had similar results as far as the color gamut.


I'd like to know if my strategy for compensating for this problem is reasonable/correct. My thinking is that, since there is no CMS on this HDTV, I should use a custom color target based on the existing primary locations for this TV. In order to do this, I was going to use the color target editor in CalMAN and put in that matrix the actual values of x and y for the red, green, and blue primaries and then adjust the color decoder as outlined in the "Adjusting the Color Decoder Using a Meter" section of the CalMAN documentation.


Would this be the correct approach to take? Thanks!

 

TC-P50S1_Bluray_Standard_PostCalSummary.pdf 103.123046875k . file
 

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I am pretty new at this but looking at your graphs your set looks way too dark. Your Y at 100% is only 17 and should be between 30 and 40. Also your luminance tracking is to the left of your target line. If you increase contrast it will help both I believe.

As for your orig question.......I don't know..sorry
 

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Quote:
Originally Posted by donnymac51 /forum/post/16995224


I am pretty new at this but looking at your graphs your set looks way too dark. Your Y at 100% is only 17 and should be between 30 and 40. Also your luminance tracking is to the left of your target line. If you increase contrast it will help both I believe.

As for your orig question.......I don't know..sorry

Thanks. I was shooting for 18 fL, which is what I have my set at home set to for night viewing (SMPTE specs, I think?). I will have to futz around with the contrast a bit and look at the effect on the luminance histogram, though. Thanks again!
 

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Quote:
Originally Posted by gerianne /forum/post/16995860


Thanks. I was shooting for 18 fL, which is what I have my set at home set to for night viewing (SMPTE specs, I think?). I will have to futz around with the contrast a bit and look at the effect on the luminance histogram, though. Thanks again!

Good luck. 18 just seems dark to me but everyone has different tastes and viewing environments. Only prob is if you raise your graph then your 18fl will also increase I believe. I am new at this and just going by what happened when I did my own display recently.
 

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I would target 80cd/m² (23.35fL) for video white on direct-view displays, and 40cd/m² for projectors, as that is the target specified in many ITU-R and EBU technical documents. I believe SMPTE actually specifies 30fL for monitor brightness, though I haven't seen this myself. (I can get ITU/EBU documents free, you have to pay for SMPTE ones)


When measuring a power-limited display such as a Plasma, I would use 1% area patterns as specified by the EBU (more specifically, a square of picture height ÷ 7.5) otherwise your measured values are potentially lower than they should be.


With a Pioneer LX5090 that has the energy saving modes disabled, a 25% area window would give you readings that are around 11% dimmer than they should be, and are potentially non-linear if the power limiter eases up on darker patterns.
 

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Quote:
Originally Posted by andrewfee /forum/post/16999983


I would target 80cd/m² (23.35fL) for video white on direct-view displays, and 40cd/m² for projectors, as that is the target specified in many ITU-R and EBU technical documents. I believe SMPTE actually specifies 30fL for monitor brightness, though I haven't seen this myself. (I can get ITU/EBU documents free, you have to pay for SMPTE ones)


When measuring a power-limited display such as a Plasma, I would use 1% area patterns as specified by the EBU (more specifically, a square of picture height ÷ 7.5) otherwise your measured values are potentially lower than they should be.


With a Pioneer LX5090 that has the energy saving modes disabled, a 25% area window would give you readings that are around 11% dimmer than they should be, and are potentially non-linear if the power limiter eases up on darker patterns.

When I did this calibration I used the AVS HD 709 disk and the windowed patterns on it. If I'm understanding you correctly, on a 50" diag (about 25" high), the window pattern should be 25/7.5 or 3" high. Seems very small - where do you find that size window? The windows on the AVS HD disk are the smallest I've used but are about 9.5" high (on this display) and their area is about 15% of the total screen area.


Do I have this right, or am I doing something wrong?
 

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Quote:
Originally Posted by gerianne /forum/post/17000180


When I did this calibration I used the AVS HD 709 disk and the windowed patterns on it. If I'm understanding you correctly, on a 50" diag (about 25" high), the window pattern should be 25/7.5 or 3" high. Seems very small - where do you find that size window? The windows on the AVS HD disk are the smallest I've used but are about 9.5" high (on this display) and their area is about 15% of the total screen area.


Do I have this right, or am I doing something wrong?

A 1% area pattern should be very small, the patterns specified by the EBU look like this:




On smaller displays, or when using a non-contact meter such as the X-Rite Hubble, I find that I have to go up to around 5% or the meter may not read things correctly. Anything above 40" or so can probably use the 1% area patterns without any issues.


Most/all calibration discs I've seen have patterns in the 15-25% area which is too large for most CRTs/Plasmas. (and probably OLED in future)


I either use custom patterns that I have created myself, or the CalMAN pattern generator set to 10/13%. (10% will give you a 1% area pattern, but 13% will give you one with the correct height which may be better depending on the size of the screen and meter used)



Here is how two recent Pioneer displays respond to window size (APL) when peak white was calibrated to 30fL with power saving disabled:





If you're in the 10-15% range, you're maybe ok, as you've only lost ≈7-10% brightness, but it should really be 1% if you want accurate measurementsespecially for gamma. (the problem is that a power limiter may restrict white, but not have any effect on 50% grey for example)



If I remember correctly, EBU-Tech 3325 is one of the documents that goes into detail about this.
 

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Quote:
Originally Posted by andrewfee /forum/post/17000472


A 1% area pattern should be very small, the patterns specified by the EBU look like this:


...If I remember correctly, EBU-Tech 3325 is one of the documents that goes into detail about this.

Wow, that really does make a big difference, doesn't it? Thanks so much for the great post and for the additional info!
 

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Discussion Starter · #18 ·

Quote:
Originally Posted by andrewfee /forum/post/16978121


Firstly, calibrate your display as close to the Rec. 709 target as possible.


When that is done, switch from the calibration window to the main CalMAN one.


Go to Tools and Editors > Color Target Editor

If you have already done greyscale calibration, uncheck the Lock White xy and CCT option. Leave RGB Y etc. locked.


This will adjust the RGBCMY luminance targets and secondary positions (CMY) to be correct based on your RGB xy values and display's white balance.


Set Level to 75%. Take a reading of 75% white, red, green and bluethis will prompt you to create a name for your new colour target. These readings are saved automatically.


Switch back to the main calibration window and your colour target should have automatically been selected.


If you want to verify this or change the target, go to Options > Grayscale > White Point Target.


This should now be set up to use the correct target luminance values and CMY positions based on your display.



Sounds more complicated than it really is when it's written out like this.

Andrew, I tried this and saw how it affected my targets for CIE. Very interesting. Thanks for this useful bit of info. Interestingly enough even after applying the custom targets my Red was too saturated (but not by as much). I'm suspecting I maybe took the wrong approach when setting the RGB levels. They are balanced, but to get them that way I pushed up the RGB Gains for Red and Blue. I'm thinking that may be why both of these are now above the target Y for CIE. Is the smarter approach to hit the two point RGBs by trying to lower the "higher" bars rather than boosting the lower?

Quote:
Originally Posted by andrewfee /forum/post/17000472


A 1% area pattern should be very small, the patterns specified by the EBU look like this:




On smaller displays, or when using a non-contact meter such as the X-Rite Hubble, I find that I have to go up to around 5% or the meter may not read things correctly. Anything above 40" or so can probably use the 1% area patterns without any issues.


Most/all calibration discs I've seen have patterns in the 15-25% area which is too large for most CRTs/Plasmas. (and probably OLED in future)


I either use custom patterns that I have created myself, or the CalMAN pattern generator set to 10/13%. (10% will give you a 1% area pattern, but 13% will give you one with the correct height which may be better depending on the size of the screen and meter used)



Here is how two recent Pioneer displays respond to window size (APL) when peak white was calibrated to 30fL with power saving disabled:





If you're in the 10-15% range, you're maybe ok, as you've only lost ≈7-10% brightness, but it should really be 1% if you want accurate measurementsespecially for gamma. (the problem is that a power limiter may restrict white, but not have any effect on 50% grey for example)



If I remember correctly, EBU-Tech 3325 is one of the documents that goes into detail about this.

Again, some very interesting info.
 

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I am not seeing this effect on a Pioneer 5020.


The result of using 1% patterns is to get higher readings across the entire grayscale. Thus, the gamma is the same. The only difference is peak output, which measures about 10% higher with 1% patterns.


The Before is 1% patterns. The After is regular (approx. 15%) patterns.


The fact that even at 10% stim the 1% pattern reads brighter tells me that this effect has nothing to do with the voltage limitations of the panel.

 

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Thanks for taking the time to measure that Tom. I did say that 10-15% patterns were probably still ok.


That said, it does seem to be having some effect on gamma in the graph you posted, and a 10.5% change in brightness at each point should keep gamma the same. (Also, not that it's a huge difference, I noticed your calibration software is actually using 2.22 as the target gamma and not 1/0.45)


Using the using the data you posted, the difference in the gamma targets is ≈10.5%, so I'll use that as the reference line.


The 1% measured data against the 15% data doesn't seem to be a linear change in brightnessif that were the case, you would see all values shifted by 10.5%. (matching the target line)




And not only that, even if the change was linear, if you're trying to hit a specific target brightness (say 80cd/m² for peak video white) it still means you're 10.5% off target when using the 15% patterns.



Not all displays respond the same eitherPanasonic panels respond quite differently from Pioneer, different CRTs have a different response to window size etc.


While some displays might be fine with larger patterns, it just seems that you would be best off using 1% to be sure?
 
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