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Sorry if I'm picky, so the Luminance under the CMS is the "Y" value, but isn't it also the same as RGB Gain / Bias? Or the value of the gain?

So the red arrows I made on the attached photo are correct in behavior?
That is, the shift of the value "x" and "y" in plus and minus ....

I ask because I realized that some points do not move, for example on the BLUE even if I put -20 on "x" the point does not move, I considered a limitation of the projector.

Fabio
 

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Sorry if I'm picky, so the Luminance under the CMS is the "Y" value, but isn't it also the same as RGB Gain / Bias? Or the value of the gain?

So the red arrows I made on the attached photo are correct in behavior?
That is, the shift of the value "x" and "y" in plus and minus ....

I ask because I realized that some points do not move, for example on the BLUE even if I put -20 on "x" the point does not move, I considered a limitation of the projector.

Fabio
The luminance you adjust under CMS is different from the RGB gains.

You cannot increase the saturation beyond the projector’s native gamut.
 

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Sorry for my late answer but here is the chc file.
https://mega.nz/#!hMcnQYJA!sYA7CeL-7dTuoONE8qEqgXFyMLBmJKnncp-ZKQxTGY0

It is consists a near black and near white measurments to.
I changged

R-Gain: from 100 to 91
G-Gain: from 100 to 94
B-Gain: 100 untouched

R-Offset: from 256 to 253
G-Offset: from 256 to 251
B-Gain: 256 untouched
I'm not sure why you would reduce the R-Gain and R-Offset so much. R readings are way below the G and B levels, which could have caused the cyan cast.

 

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I'm not sure why you would reduce the R-Gain and R-Offset so much. R readings are way below the G and B levels, which could have caused the cyan cast.

For the calibration I used Calman and I did not see that R readings are way too below. But in HCFR You are rigth. I will recalibrate it with the hcfr.
Could You suggest anything for grayscale calibration?
I use 30 and 80 IRE patterns for the 2 point grayscale calibration.
Is there any rule for not to touch green channel or only decrease the channels and not to allowed increase any of the channels?

In the settings of HCFR for the display type what is correct settings for a DLP projector?
 

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For the calibration I used Calman and I did not see that R readings are way too below. But in HCFR You are rigth. I will recalibrate it with the hcfr.
Could You suggest anything for grayscale calibration?
I use 30 and 80 IRE patterns for the 2 point grayscale calibration.
Is there any rule for not to touch green channel or only decrease the channels and not to allowed increase any of the channels?

In the settings of HCFR for the display type what is correct settings for a DLP projector?
If you're re-calibrating then reset all controls to factory default and measure and save the greyscale before making any adjustments.

Increasing gain settings can often lead to clipping of those channels, so if green is higher than red and blue you may have to decrease green.

For lamp-based projectors use projector is the display type.
 

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If you're re-calibrating then reset all controls to factory default and measure and save the greyscale before making any adjustments.

Increasing gain settings can often lead to clipping of those channels, so if green is higher than red and blue you may have to decrease green.

For lamp-based projectors use projector is the display type.
Thx.
And whats the point for an example if the red is 115% green is 110% and blue is 90%? Decrease red to match green and increase blue to match green? Or decrease and increase everything till 100%?

In the Display Type I only have 1 Projector option:
https://www.avsforum.com/forum/attachment.php?attachmentid=2688986&thumb=1

For the measurement I chose none refresh display for display type.
 

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Thx.
And whats the point for an example if the red is 115% green is 110% and blue is 90%? Decrease red to match green and increase blue to match green? Or decrease and increase everything till 100%?

In the Display Type I only have 1 Projector option:
https://www.avsforum.com/forum/attachment.php?attachmentid=2688986&thumb=1

For the measurement I chose none refresh display for display type.
As mentioned previously, increasing gain can potentially leading to clipping. I would deacrease red and green to match blue, or confirm there’s no clipping when increasing blue.

Yes, there is only one projector option for UHP lamps.
 

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As mentioned previously, increasing gain can potentially leading to clipping. I would deacrease respd and green to match blue, or confirm there’s no clipping when increasing blue.

Yes, there is only one projector option for UHP lamps.
But if I decrease green it won't be break the gamma curve?
 

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But if I decrease green it won't be break the gamma curve?
No, that's a common misconception. The green gain control will affect the overall brightness but won't affect gamma much.

As suggested previously, it's very easy check these things out, using the HCFR internal patterns.
 

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After a new look in HFCR i can se there are two choices related to Oled.
- LED OLED (EDR for OLED created with primaries R, G, B, W)
- WRGB OLED (LGB7) (2017))


Anyone who knows the difference between these two? Because my screen is the 2016 model, i assume I should use the first alternative?


Since my LG OLED is 2016 and that only shows an option for 2017, I'm also curious which of these new options will be the best choice when I recalibrate soon?
 

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Hi guys,

I've been reading for a full day now, and I'm less sure than ever which information applies to my use case. So I'm asking directly:

Situation: 4k/SDR/HDR LED Projector calibration using i1 Display Pro. Previous experience calibrating in 709 using HCFR.

1. Is there a specific correction or profile I need in general for an LED based projector? Does an i1 Display Pro even work?
2. For HDR, most of the discussion here is using OLEDs. Which settings in HCFR would you recommend for calibrating an LED projector? I can use CCast, a RPi running PGenerator should also be an option, internal patterns if it's not HDR. Should a projector even be calibrated using HDR patterns? It's effectively tone-mapped anyway. I read mentions of SDR in 2020, how would that work?

If anyone can help me get a foot back in the door, I'd be eternally grateful. Right now I'm missing a piece to start understanding.
 

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Situation: 4k/SDR/HDR LED Projector calibration using i1 Display Pro. Previous experience calibrating in 709 using HCFR.
1. Is there a specific correction or profile I need in general for an LED based projector? Does an i1 Display Pro even work?
Colorimeters like the i1DisplyPro will need to have the profile for the light source. If you don't have the profile try using the generic non-refresh, but of course one can't tell how accurate that is for your display. Ideally you should rent a spectrophotometer to create a correction matrix.

2. For HDR, most of the discussion here is using OLEDs. Which settings in HCFR would you recommend for calibrating an LED projector? I can use CCast, a RPi running PGenerator should also be an option, internal patterns if it's not HDR.
If your projector can be placed manually in the HDR mode then even internal patterns will work.

Should a projector even be calibrated using HDR patterns? It's effectively tone-mapped anyway.
Tone mapping should only be done for highlights > 50% input (code value 504). Below that the EOTF should follow the ST.2084 PQ curve, with a "scale factor" for projectors.

I read mentions of SDR in 2020, how would that work?
That's just one way of measuring a subset of BT.2020. Other alternatives are P3 in BT.2020, or 50% saturation in BT.2020.
 

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Hi guys,

I've been reading for a full day now, and I'm less sure than ever which information applies to my use case. So I'm asking directly:

Situation: 4k/SDR/HDR LED Projector calibration using i1 Display Pro. Previous experience calibrating in 709 using HCFR.

1. Is there a specific correction or profile I need in general for an LED based projector? Does an i1 Display Pro even work?
2. For HDR, most of the discussion here is using OLEDs. Which settings in HCFR would you recommend for calibrating an LED projector? I can use CCast, a RPi running PGenerator should also be an option, internal patterns if it's not HDR. Should a projector even be calibrated using HDR patterns? It's effectively tone-mapped anyway. I read mentions of SDR in 2020, how would that work?

If anyone can help me get a foot back in the door, I'd be eternally grateful. Right now I'm missing a piece to start understanding.


SDR2020 is a profile you would use when your tone-mapping is done externally such as in a UHD BluRay player, madVR or a Lumagen.

So your display will be in SDR mode meaning power law 2.2 or 2.4 gamma, but you still want to take advantage of the wider color gamut from HDR, hence the 2020 as in mapped to BT2020 gamut with your display in a BT2020 gamut mode.

Not every display is capable of using its wide gamut mode with SDR gamma, but many are.
 

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Colorimeters like the i1DisplyPro will need to have the profile for the light source. If you don't have the profile try using the generic non-refresh, but of course one can't tell how accurate that is for your display. Ideally you should rent a spectrophotometer to create a correction matrix.



If your projector can be placed manually in the HDR mode then even internal patterns will work.



Tone mapping should only be done for highlights > 50% input (code value 504). Below that the EOTF should follow the ST.2084 PQ curve, with a "scale factor" for projectors.



That's just one way of measuring a subset of BT.2020. Other alternatives are P3 in BT.2020, or 50% saturation in BT.2020.
Just curious, where would one rent a spectrophotometer? I've been looking and I can't find anyplace to rent one.
 

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Hi, I have a question about when measuring greyscale. Should the first patch (16) be completely black? Because i think it should be and i cant figure out how to make that happen...Only way I've been able to do that has been to change the GDI from 16-235 to 0-255 but that screws up the gamma curve really hard.
 

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Hi, I have a question about when measuring greyscale. Should the first patch (16) be completely black? Because i think it should be and i cant figure out how to make that happen...Only way I've been able to do that has been to change the GDI from 16-235 to 0-255 but that screws up the gamma curve really hard.
If 16 is “slightly grey” it means your TV’s Brightness control needs to be adjusted. If it’s “very grey” then there’s a level mismatch.

If you can attach the HCFR data files for both GDI settings it will help diagnose.
 

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Here are the chc files. Been trying to figure this out for a couple days and I cant for the life of me figure it out on my own.
You cannot adjust the Brightness to bring 16 down?
 
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