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Discussion Starter #1
I apologize for creating a second thread to discuss my calibration questions but I will post any further questions in this topic.

I've just calibrated an older Vizio M651d-A2R (1080p TV) using CalMAN 5.7.3.9 (Home Enthusiast) and PGenerator (thanks for the help everybody!).

Here is my colorspace calibration:


Here is my post calibration report:


However, here it a saturation sweep:


During the colorspace calibration I used my TV 6-axis color calibration to adjust saturation/hue/luminance for the primary and secondary colors and the DeltaE for each color is below 2.

However, the saturation sweep seems extremely terrible with DeltaE around 14 for some colors.

What could I be doing wrong?

Here are some additional pictures of my calibration process.

Thanks SO MUCH for any help! (and I apologize for asking so many questions!)
 

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I apologize for creating a second thread to discuss my calibration questions but I will post any further questions in this topic.

I've just calibrated an older Vizio M651d-A2R (1080p TV) using CalMAN 5.7.3.9 (Home Enthusiast) and PGenerator (thanks for the help everybody!).

Here is my colorspace calibration:


Here is my post calibration report:


However, here it a saturation sweep:


During the colorspace calibration I used my TV 6-axis color calibration to adjust saturation/hue/luminance for the primary and secondary colors and the DeltaE for each color is below 2.

However, the saturation sweep seems extremely terrible with DeltaE around 14 for some colors.

What could I be doing wrong?

Here are some additional pictures of my calibration process.

Thanks SO MUCH for any help! (and I apologize for asking so many questions!)
1. Most displays are not linear in their color performance. Just because 100% is good absolutely does not mean that 40% will also be. It's been suggested for years that if you have a CMS with only one target point per color, you adjust at ~75%. This is far easier for most displays to achieve and more closely duplicates color saturation in actual content. It's the reason that many color bar patterns used to adjust color and tint back in the day were at 75%.
2. Take a look at your 100% White luminance. If you are calibrating SDR, this is likely far too high. The problem with doing this is that you can hit a point at which one or more of your primary colors simply run out of steam and cannot hit their luminance targets at that level. This also adversely impacts your secondaries. Most people calibrate SDR for between 100 to 150 nits at 100% White to avoid this.
3. Most manufacturers' CMS implementations are extremely poor and flat-out suck. They can cause artifacts with anything but tiny changes. Trying to adjust them at the high luminance you have set is begging for failure.

I recommend starting over with everything set to defaults and 100% White at no higher than 150 nits.
 

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Discussion Starter #3
Thanks so much for your advice!

Would you recommended calibrating 100% white luminance (ie. 150 nits) on a 10% window or 100% full pattern? (I believe that makes a big difference on max TV luminance?)
 

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Thanks so much for your advice!

Would you recommended calibrating 100% white luminance (ie. 150 nits) on a 10% window or 100% full pattern? (I believe that makes a big difference on max TV luminance?)
If your Vizio is an LCD/LED, you can use full screen patterns.
 

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During the colorspace calibration I used my TV 6-axis color calibration to adjust saturation/hue/luminance for the primary and secondary colors and the DeltaE for each color is below 2.
Hi, I am not familiar with Calman's workflow buit what color patterns did you use to calibrate? Were they 100%sat/100%lum patterns? Then as Rolls-Royce says, this may not be giving you the optimum calibration for the entire color gamut. You may want to try calibrating 75%sat/75%lum patterns if Calman offers that option. Otherwise, try 100%sat/75%lum ones. Also, remember that you need to get the contrast/brightness/gamma and grayscale dialed in first since these will affect the color gamut.

cheers,

--tom
 

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Discussion Starter #6
Thanks again so much for the help.

I've verified that the color sweep patterns are using 75% stimulus (luminance?) and I adjusted the backlight to 133 nits with a 100% white pattern.

The grayscale seems OK:
3116884


However, I tried adjusting the 11-point grayscale and it's a nightmare. (with a DeltaE under 2 I don't think it's necessary but I wanted to learn)

When I adjust any of the 11 points (plus 5%) it seems like the next and/or previous points become completely out of balance. Is it normally this difficult to adjust multi-point grayscale or is it because I'm already close to DeltaE 0?

Here is the colorspace without any adjustments:
3116888


However, I can't seem to fix the primaries. Here is blue:
3116890


If I understand correctly, the saturation is much too high, and the hue/luminance are also high.

The closest I can come to fixing it is to adjust blue saturation (-26) and hue (-50 which is the lowest it goes):
3116893


Also, if I adjust "Brightness" in my 6-axis CMS, it doesn't change the DeltaL at all...

I'm so sorry for so many pictures/questions. I really appreciate the help so much.
 

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Manual multipoint gray scale can be a real bear unless you do a two-point first (if the set lets you do it) followed by multipoint to fine tune individual points.

For the gamut adjustment, remember that each primary is not really a single pure color, but a blend done by the set's color circuits. So consequently, another way to try and reduce saturation on an oversaturated primary without bottoming out any of the controls is to boost saturation a bit on one or both of the other two primaries (Red and Green in this case).
 

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Discussion Starter #8
Thanks. I've performed the two-point grayscale first (30% and... 100% I think?) but the multi-point is still really difficult.

The DeltaE is under 2 so is that considered pretty good? (I've heard that under 3 should be the target, so under 2 sounds quite decent?)

Thanks for the advice on the gamut adjustment. I'm not at my calibration PC, but I think CalMAN shows the components (RGB) of each primary. Is the goal to have the primaries only consist of that individual color?
 

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Thanks. I've performed the two-point grayscale first (30% and... 100% I think?) but the multi-point is still really difficult.

The DeltaE is under 2 so is that considered pretty good? (I've heard that under 3 should be the target, so under 2 sounds quite decent?)

Thanks for the advice on the gamut adjustment. I'm not at my calibration PC, but I think CalMAN shows the components (RGB) of each primary. Is the goal to have the primaries only consist of that individual color?
Under 2 is acceptable, but not ideal. Lower is better. One thing you can do to improve your two point is to run a complete 10/11-point reading ("read series") every time you adjust. This way you can see how the entire range is responding. The high and low two point adjustments overlap, so this is a good thing to know.
No, the primaries need to be mixtures, as the native primaries are generally far off of those needed for Rec709 or 2020. I personally ignore those RGB displays for the primaries, concentrating only on the Delta L, C, and H. Those are calculated by CalMAN vs the targets in the Rec specifications you are calibrating to. For primaries, L is the most important measure, while for secondaries, it's H.
 

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Discussion Starter #10
Reading the series does help but is very time consuming and still a bit difficult but I understand what you're saying.

I'm not sure what you mean about the high/low two point adjustments overlap. (my two-point adjustments are using 20 and 80 so I know they are also included in the multi-point adjustment if that's what you mean?)

As for the color adjustments, the display doesn't seem to respond to certain adjustments?

For example, I was able to adjustment red brightness and get DeltaL to around 0. However, green brightness is too low but adjusting it on my CMS doesn't change DeltaL. I can decrease the brightness and see DeltaL changing but raising it even to 50 doesn't do anything.

It might also be worth noting that my meter (i1 Display Pro) is from December 2013 so I'm not certain how accurate (or if it's working correctly?) any longer.
 

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Reading the series does help but is very time consuming and still a bit difficult but I understand what you're saying.

I'm not sure what you mean about the high/low two point adjustments overlap. (my two-point adjustments are using 20 and 80 so I know they are also included in the multi-point adjustment if that's what you mean?)

As for the color adjustments, the display doesn't seem to respond to certain adjustments?

For example, I was able to adjustment red brightness and get DeltaL to around 0. However, green brightness is too low but adjusting it on my CMS doesn't change DeltaL. I can decrease the brightness and see DeltaL changing but raising it even to 50 doesn't do anything.

It might also be worth noting that my meter (i1 Display Pro) is from December 2013 so I'm not certain how accurate (or if it's working correctly?) any longer.
Look at the high and low grayscale adjustments (bias and gain, cuts and drives, etc, whatever the manufacturer calls them) as parametric controls. They don't start and end at discrete points, but overlap in the center of the gray scale, each forming a bell curve. Think of a suspension bridge. This is the root cause of the dreaded "blue hump" where blue bulges upward from around 40% to about 70% due to adjustment of blue at both ends of the scale. Doing a full-scale multipoint read is a little time consuming, yes. But it makes it much easier to coordinate your low and high end adjustments because you can see the big picture as it happens. You're trying to even out the red, green, and blue traces and move them to the target line as much as you can before moving to multipoint.

If you can't bring up a primary with the CMS control, it means that color is already as bright as it's going to get. You can improve this by using the set's Color control. Put the CMS controls back at their defaults first, then bring up Color until the primary that's lowest in luminance is where it needs to be. You may then need to lower the luminance on the other two in the CMS, but that's OK. These controls work far better with fewer issues when cutting rather than boosting.
 
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