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A "typical" PC LCD monitor has a contrast ratio 1000:1. With a gamma of 2.2, the left pattern 6,6,6 is below the black level, and right pattern 15,15,15 is barely above the black level.

Thus, it's not really the "fault" of the calbration software. Specifying black-point compensation during calibration will help.
I just read through an old (2012) thread that describes this issue in great depth

http://www.avsforum.com/forum/139-display-calibration/1409045-how-power-law-gamma-calibration-can-lead-crushed-blacks-6.html#post22254372

in particular, post #172 sums it up:
Following the power law curve exactly as far "down" the curve as we can adjust, will ensure that at some point (~4.6% Stimulus on my set @ 2.2 gamma) near blacks will simply merge with black (aka clipping.) IOW, if we follow standard practice for setting black level, but neglect to apply at least a linear offset black level compensation to our power law EOTF, we haven't really solved anything.
Most of the PC Monitor calibration software uses 2.2 gamma as the default target; coupled with the low contrast (1000:1) and high ambient light level, the end result is severe black clipping.
 

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I just read through an old (2012) thread that describes this issue in great depth

http://www.avsforum.com/forum/139-display-calibration/1409045-how-power-law-gamma-calibration-can-lead-crushed-blacks-6.html#post22254372

in particular, post #172 sums it up:


Most of the PC Monitor calibration software uses 2.2 gamma as the default target; coupled with the low contrast (1000:1) and high ambient light level, the end result is severe black clipping.
The simple answer is that 2.2 is actually not bad in this respect. The problem is when people try to use 2.4 power law. That will lead to obviously crushed blacks.

2.2, or 2.22, is a reasonable choice. Arguably, BT.1886 is better and the closest thing we have right now to an actual standard for gamma (despite the fact that it doesn't use 2.22, the average gamma with BT.1886 will often be very close to this). Of course, the details on this vary depending on the white/black level of the display.
 

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I have an OLED display and get clipped blacks on 2.2 gamma, and it can't handle gamma properly below 2.0 without severe washout.

Does anyone have an excel spreadsheet that tells me what the gamma values should increase by each IRE? Or is there a table I can make somewhere?
 

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I have an OLED display and get clipped blacks on 2.2 gamma, and it can't handle gamma properly below 2.0 without severe washout.

Does anyone have an excel spreadsheet that tells me what the gamma values should increase by each IRE? Or is there a table I can make somewhere?
That should likely be handled by your calibration software.

How are you measuring the luminance response of the display?
 

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Also BT.1886 for a 1000:1 display and sRGB are incredibly close. like 0.2 dE close.
Interesting. I thought the "standard" sRGB does not include Black Level Compensation, unlike BT.1886?
 

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Interesting. I thought the "standard" sRGB does not include Black Level Compensation, unlike BT.1886?

That's at 5% through 100%, while sRGB technically has 0% defined as 0, if you don't actually calibrate below 5%, the interpolation from 0%-5% will be the same as with BT.1886 because the targets for 5% and up are so similiar.

Remember this is the intent for sRGB. in 1996, the idea of measuring below 5% with a field instrument was crazy. sRGB was not designed to provide a calibration target a 1% or 2%, the simplified offset just pushed the black floor up.

sRGB was designed to encode the actual response of the CRTs in use at the time. BT.1886 also sought to quantify the reproduction of CRTs. The fact that they are so similar is not a coincidence. With the advancement of technology BT.1886 did intend to describe the display performance coming out of black, so the size of the next step coming out of black is relative to the black level. This is much better than simple black offset added to a standard power function, and following any formula down to where it clips in to the display's black level is never recommended. If you want to calibrate anything below 5%, BT.1886 is the only formula I would recommend.
 

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That should likely be handled by your calibration software.

How are you measuring the luminance response of the display?
I am using chromapure standard and a i1d3. HCFR appears to be giving me different results, and I don't think calman provides a checker tool for anything other than color.

So I have multiple software reporting different results, very frustrating.


Here is my current Gamma, this is for me to even see shadow detail and it is STILL clipping black.
 

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What are you using to do the actual calibration?

You said the display is an OLED?

If that's the case, the black level should be zero, which isn't what that graph indicates.
 

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What are you using to do the actual calibration?

You said the display is an OLED?

If that's the case, the black level should be zero, which isn't what that graph indicates.
I don't really understand. I tried making the black level darker, but all it did was make shadows impossible to see. If I have to crank the brightness and gamma up that high just to see shadow detail, how exactly is setting my black level to 0 going to help?

I don't see how I can make black level 0. My i1d3 already struggles reading IRE 5.
 

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I don't really understand. I tried making the black level darker, but all it did was make shadows impossible to see. If I have to crank the brightness and gamma up that high just to see shadow detail, how exactly is setting my black level to 0 going to help?

I don't see how I can make black level 0. My i1d3 already struggles reading IRE 5.
It should struggle to measure 5%, that should be a piece of cake for an i1D3.

There are many possible issues.

What display are you calibrating?
How much ambient light do you have?
Make sure you're setting black level with a visual pattern. You should use a the brightest brightness setting where bitlevel 16 blends into bitlevel 1.

Once you have the black level correctly set, what other controls do you have? Do you have a multipoint grayscale system? An OLED probably will visually crush 17 and 18, but this is correct to the spec and you'll need a lot of control over the signal to change that.
 

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It should struggle to measure 5%, that should be a piece of cake for an i1D3.

There are many possible issues.

What display are you calibrating?
How much ambient light do you have?
Make sure you're setting black level with a visual pattern. You should use a the brightest brightness setting where bitlevel 16 blends into bitlevel 1.

Once you have the black level correctly set, what other controls do you have? Do you have a multipoint grayscale system? An OLED probably will visually crush 17 and 18, but this is correct to the spec and you'll need a lot of control over the signal to change that.
This is the issue. Yes the display has been calibrated, I haven't spent time doing serious amounts of calibration since I don't have my i1pro yet.


If I calibrate to 2.2 gamma, it is IMPOSSIBLE to see reference 17. This is why I am not sure what I am doing wrong. Even in pitch black, brightness to 100 I never see 17 flash. It only becomes visible in 2.0 gamma or higher.

I need to see 17, it is not an option. Video games uses refrence 17 a lot more than movies do.
 

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You still haven't said what the display is, or what controls you are using to calibrate the display.

But from your description of the way the controls work, it sounds like it ships with controls that don't work correctly. This is not uncommon and no amount of fiddling with fix controls that are broken.

Set it up how you want it. But if it can't do two things correctly at the same time, it's probably just a limitation of the display.
 

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That's at 5% through 100%, while sRGB technically has 0% defined as 0, if you don't actually calibrate below 5%, the interpolation from 0%-5% will be the same as with BT.1886 because the targets for 5% and up are so similiar.
Thanks for the explanation. Finally I see the whole picture (pun intended).
 

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You still haven't said what the display is, or what controls you are using to calibrate the display.

But from your description of the way the controls work, it sounds like it ships with controls that don't work correctly. This is not uncommon and no amount of fiddling with fix controls that are broken.

Set it up how you want it. But if it can't do two things correctly at the same time, it's probably just a limitation of the display.
I have an EC9300 LG OLED TV, I used both 2 point for 30 IRE and 80 IRE, then used 20 point for everything else. I am also using chromapure standard with the standard profile, I don't have a correction table until my i1pro ships to me on tuesday.


I see on the forums people are posting 2.4 gamma curves and do not get a crushed black issue, this is frustrating because I have the exact same display and I cannot do the same.
 

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If you have a 20 point, I would set black level correctly then raise 5% up till you're satisfied.

As I mentioned earlier.

An OLED is off for black when correctly set.
BT.1886 is a basic 2.4 power law for true black.
1 DICOM JND above black is 0.049 nits, so values less than that are likely imperceptible.
0.049 is roughly 4.2% or bit level 25, assuming 100 nit max output.

Therefore people maybe exceedingly happy with the performance of their television while you are not.
 

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Just to mirror that, seeing 17 isn't the goal, and shouldn't be a goal.

You can measure 17 to make sure that it is providing more like than 16, that should be true, but your ability to perceive that step isn't important.
 

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I imagine these same people aren't playing video games, because it's super dark. Looking up online video games should be using the srbg curve, which is basically bt1866 but brighter. I guess I'll just continue to use bt1866 because I've tried everything and been very dissatisfied

I have tried doing the black level to be at the exact tipping point from 0, spent like 1 hour calibrating IRE and 2.2 gamma. It was realy really dark, it was equivalent to running a display in full mode with a limited display, it was that bad.


It only became acceptable at 2.0 gamma, which is the level at which I can see most shadow detail but not reference 17. I then tried 1.8 gamma and saw refrence 17 but then I got picture quality distortion, skin tones appeared to have blotches on their faces.

I am going to try calibrating at 1.9 base gamma when I get my Spectro and that will probably fix my issue.
 

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I am going to try calibrating at 1.9 base gamma when I get my Spectro and that will probably fix my issue.
Calibrating your colorimeter with a spectro will improve the colour accuracy, but won't do anything for the gamma.
 
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