# White Point Calibration



## AtomicAgeZombie

My Samsung Un60D7000 has two seperate White Point controls, one is the offset & gain, the other is the 10p. If I don't touch the offset/gain, the 10p does virtually nothing. So I used to offset/gain to adjust 20 & 80, got them near perfect, switched to the 10p to fine tune everything, and 50-70 couldn't really be adjusted. (they were really off the chart) What am I dong wrong?

Also, I'm using Calman 4 with an X-Rite Display Pro Retail. Feel free to talk to me like a dummy and walk me through this.

Thanks!


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## mechman

Post a screen grab of the results. What are the dEs?

One thing that I read somewhere was that for the D7000 on the 2 point grayscale you should calibrate 30 and 100%. Most other displays you would use something like 20 and 80 or 30 and 70. After that you should go and fine tune the rest under the 10 point grayscale.


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## lcaillo

AtomicAgeZombie said:


> My Samsung Un60D7000 has two seperate White Point controls, one is the offset & gain, the other is the 10p. If I don't touch the offset/gain, the 10p does virtually nothing. So I used to offset/gain to adjust 20 & 80, got them near perfect, switched to the 10p to fine tune everything, and 50-70 couldn't really be adjusted. (they were really off the chart) What am I dong wrong?
> 
> Also, I'm using Calman 4 with an X-Rite Display Pro Retail. Feel free to talk to me like a dummy and walk me through this.
> 
> Thanks!


Off the chart how? I suspect that if you use the offset and gain it disables the 10 point correction by design.


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## AtomicAgeZombie

I wish I had saved the info, I got frustrated and didn't save. I just reset my settings and quit messing with my set for the day. I'll have screens over the weekend.

Using the 2 point (offset/gain) doesn't disable the 10p. I've used them in conjunction before, it just seems like I've forgotten how to do this. Ugh. I can really nail the color gamut, but the white balance really hurts my brain.

Here's a link to the emanual if anyone feels like checking out the menu options. Maybe you'll see something I don't.

http://downloadcenter.samsung.com/content/UM/201201/20120128100021210/[ENG_US]GPATSCA-1025.pdf


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## lcaillo

What are the other settings that you are starting with? Some settings like vivid modes may have some unusual gamut or gamma responses. I am not familiar with this series of sets, so I can't offer much specific advice, sorry.


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## AtomicAgeZombie

I go with Movie mode and Warm 2. Anything other than that is too bright.


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## AtomicAgeZombie

So I got some free time to run a quick calibration. I used mechman's suggestion of 100 and 30, and it seems to have helped. My only problem now is working with the 10p. I will gladly accept any advice on how to proprly use the 10p settings. Right now, I have them disabled.


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## donnymac

What is your Contrast setting? It shoudl be set between 90-95 on the Samsungs. Anything lower starts to muck up the greyscale. On the 10 pt. start with 100 and work your way down. ONce done take a greyscale reading. You may have to go back and tweek a little. You should not have this issue on this display. You shoudl be able to get your de under 1 for each step. Dynamic contrast should be off of course. What gamma are you adjusting for?


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## donnymac

Didn't see your charts until after I posted but your greyscale looks ok. Everything is de of less than 3. Gamma also looks good.


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## AtomicAgeZombie

My contrast is 86 and brightness 50.


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## AtomicAgeZombie

Also, feel free to comment on the Color Gamut.


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## AtomicAgeZombie

@donnymac

Should I raise the contrast to 90 as a standard? If so, I'll go back and re-do to grayscale with that change.


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## donnymac

AtomicAgeZombie said:


> @donnymac
> 
> Should I raise the contrast to 90 as a standard? If so, I'll go back and re-do to grayscale with that change.


You can try to set contrast around 93-95 and then lower the backlight to keep your 100% white the same. Remember the higher the bakclight the more grey your blacks will be. Your gamma looks good so if you do try the 10 pt just adjust red and blue. If you want to tweak your gamma then you would use green to do that while in the 10 pt WB.
Try this procedure to bring in your color gamut.
•To desaturate a primary, add equal amounts of both of the other 2 primaries to it. To desaturate a secondary, add the opposing primary to it.
•To change the hue of a primary add unequal amounts of the other 2 primaries. To change the hue of a secondary, add unequal amounts of the contributing primaries.
•To decrease the lightness of a primary, reduce the amount of the primary itself. To decrease the lightness of a secondary,decrease equally the amount of the contributing primaries.
You cannot increase saturation or lightness.
Good luck,
Don


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## AtomicAgeZombie

donnymac said:


> You can try to set contrast around 93-95 and then lower the backlight to keep your 100% white the same. Remember the higher the bakclight the more grey your blacks will be. Your gamma looks good so if you do try the 10 pt just adjust red and blue. If you want to tweak your gamma then you would use green to do that while in the 10 pt WB.
> Try this procedure to bring in your color gamut.
> •To desaturate a primary, add equal amounts of both of the other 2 primaries to it. To desaturate a secondary, add the opposing primary to it.
> •To change the hue of a primary add unequal amounts of the other 2 primaries. To change the hue of a secondary, add unequal amounts of the contributing primaries.
> •To decrease the lightness of a primary, reduce the amount of the primary itself. To decrease the lightness of a secondary,decrease equally the amount of the contributing primaries.
> You cannot increase saturation or lightness.
> Good luck,
> Don


Right now my backlight is 14 (out of 20), which based on the readings in Calman, puts me in a good spot for dim & dark rooms. This weekend I'll raise my contrast and go from there.
So, just to clarify, to tweak the grayscale with the 10p, only use the red and blue. To tweak the gamma and get it closer to my 2.3 setting, I only adjust the green in 10p. Is that correct?
Also, thanks for the explanation of working with the color gamut. I'm always looking for simple breakdowns on how to do things.
One last thing, do you have a workflow suggestion or should I just stick with the Calman Standard?

Thanks.


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## donnymac

AtomicAgeZombie said:


> Right now my backlight is 14 (out of 20), which based on the readings in Calman, puts me in a good spot for dim & dark rooms. This weekend I'll raise my contrast and go from there.
> So, just to clarify, to tweak the grayscale with the 10p, only use the red and blue. To tweak the gamma and get it closer to my 2.3 setting, I only adjust the green in 10p. Is that correct?
> Also, thanks for the explanation of working with the color gamut. I'm always looking for simple breakdowns on how to do things.
> One last thing, do you have a workflow suggestion or should I just stick with the Calman Standard?
> 
> Thanks.


The green channel is the luminance of each step. If let's say your are adjusting 80 and your gamma is right on then just bring the blue and red channels to meet green. If your gamma needs adjusting then move the green to where gamma is correct or as close as you can get it. then tweak red/blue to again meet green. Remember to get an accurate gamma or Y reading for each step you must first take a reading at 100. Everything is calculated based on your reading at 100.
Not sure what workflows you have available. Try quickview if you have it as it will give you some gamma charts. Make sure you go into "options" and change the "Target exponent" to the gamma target that you want for whatever workflow you use. This will ensure that you have the correct "Target Y" in your data graph. You want to match your Y to target Y by adjusting the green channel. I hope this makes sense. Good luck.


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## AtomicAgeZombie

This is fantastic, thanks for making it easy to understand. One last thing to calrify, you mention "Target Y", I just looked at my Grayscale.pdf and noticed there were 2, target_y & target_Y_, which were you referring to?


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## donnymac

AtomicAgeZombie said:


> This is fantastic, thanks for making it easy to understand. One last thing to calrify, you mention "Target Y", I just looked at my Grayscale.pdf and noticed there were 2, target_y & target_Y_, which were you referring to?


Was referring to Y. x and y are coordinates on teh CIE chart. Y is luminance of each step.


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## AtomicAgeZombie

Got it. I'll be using this info either tomorrow night or Saturday.


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## AtomicAgeZombie

So here are the captures of round 2. It went much better this time, but I'm sure there's more I can do. Please give me feedback and tips on everything.

Thank you donnymac and mechman for your help in getting me this far.


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## donnymac

AtomicAgeZombie said:


> So here are the captures of round 2. It went much better this time, but I'm sure there's more I can do. Please give me feedback and tips on everything.
> 
> Thank you donnymac and mechman for your help in getting me this far.


Looks like you nailed it.


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## donnymac

I see a difference in your color gamut results and the post capture results. Maybe revisit that and tweak a litt more on the Cyan. If you just wanted to play some more you could tweak the greyscale using the 10 pt. As close as you are you prob wouldn't see any diff in the picture. Nice work.


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## AtomicAgeZombie

Should I not bother with the Y on yellow? Would it make any difference?

And thanks again for all of your help.


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## AtomicAgeZombie

Just saw your post about the cyan. I'll get back in there and mess around with all of that.


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## donnymac

Tweak as much as you can. Just because some colors adjust almost perfectly doesn't mean every color will. If you can make things better then go for it. If you can only get so far with a certain adjustment you just have to raise the white flag and move on to the next. It looks like you have a pretty good handle on what you are doing now.


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## AtomicAgeZombie

I just found something interesting. On my set, the white balance is 10 point, so I was under the assumption that 1 = 10% 2 = 20%... 10 = 100%, but when I try to adjust 10% with Interval 1, nothing happens. 10% seems to be adjusted with Interval 2. With that in mind, what should Interval 1 adjust?


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## AtomicAgeZombie

Any guesses?


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## lcaillo

Black level.


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## AtomicAgeZombie

What do you mean? Which pattern should I be adjusting?

And thanks for responding!


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## AtomicAgeZombie

I just ran the 10 & 11 point grayscale in Calman 5, and Interval 1 doesn't control anything. Also there is no control over 60%.

Breakdown:

1 = Nothing (that I know of)
2 = 10%
3 = 20%
4 = 30%
5 = 40%
6 = 50%
7 = 70%
8 = 80%
9 = 90%
10 = 100%

:scratch:


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## AtomicAgeZombie

Awww, c'mon. There's no way this has stumped you all. :blink:


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## lcaillo

The first setting should be adjusting your black level. This is usually adjusted on a pluge pattern. I am not familiar with this set's controls, but I would assume that you have it adjusted such that you are not seeing the difference when you make changes.


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## AtomicAgeZombie

Just to clarify, could/should I use it on the brightness pattern, or just a normal pluge? Also, what should I look for while adjusting?

Thank you for getting back to this topic!


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## tbaudoin

AtomicAgeZombie said:


> Just to clarify, could/should I use it on the brightness pattern, or just a normal pluge? Also, what should I look for while adjusting?
> 
> Thank you for getting back to this topic!


I would think any PLUGE that shows below black (16 and below). 16 not visible, 17 first visible step for video calibration. As far as which pattern, it depends on the source of the pattern. Different manufacturers/designers use differnet patterns. If you change the brightness/black level, etc. and it doesn't impact a change, then something may be clipping/clamping the control and keeping you from setting it correctly.

If this doesn't help, help me understand by telling me which PLUGE you are using and I will try to assist.

Regards,
tbaudoin


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## AtomicAgeZombie

I'll be using the DPG2000 from SpectraCal for all of my patterns.


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## AtomicAgeZombie

Samsung and CalMan 5 both released updates, one of them fixed the issue of bad readings. Everything is back to normal, Interval 1 now controls 10% and 6 controls 60%.


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## nodixe

I have noticed something similar on my es6500. I have been playing around trying with different presets/modes and I successfully calibrated game mode (standard mode only) which has 2pt wb and cms controls. Afterwards I tried just standard mode (which includes 10pt and) and noticed that interval 4 controlled 40 & 50%, 5=60%, 6= 60 & 70% etc etc. I got it to be more precise by changing contrast around. My best guess is that if contrast is too low/high it skews the wb controls. Standard mode has some peculiarities and seems like everything is overdriven (color must be set at 35) so I set my contrast lower than normal. I haven't seen this behavior in movie mode


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