R.Masciola's HDR-10 UHD Test Patterns - Page 59 - AVS Forum | Home Theater Discussions And Reviews
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post #1741 of 1765 Old 06-10-2019, 01:41 PM
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Originally Posted by ajc9988 View Post
If you are cool doing 5 instead of 4 point, go into misc. folder>Color Gamuts in BT2020 Patterns > P3 Sat Sweep in BT2020. I do agree on wanting a 0% saturation to check sat shifts in HCFR, but wanted to mention that there are 2020/P3 patterns included in the misc. folder. These are not specific to HCFR, but HCFR does NOT have official DV support at the moment. It does support the SMPTE 2084 and BT.2390 standards (the latter being a roll-off on the high end).

So, if you just change the parameters to 5 point for saturation, you can use the BT2020/P3 patterns in that folder to attempt it. You may even reach out to the HCFR thread for others with an LG C8 to ask about their successes. In the unreleased version 3.5.1.7, there is a box to use a vertex to inject DV signal. That does not mean that it is made fully for the implementation of DV though.


Why? Give a cogent reason why just the grayscale. Do you believe the company producing your set accurately set DV color space? Or are you referring to people without Spectracal that may not have proper correction of the color space due to software not yet supporting it officially? Or are you getting at it may not accurately say how to adjust the saturation and brightness within the format due to YCbCr being stretched to the RGB full in the DV standard (not a perfect explanation of what is going on AT ALL with DV, but an explanation I read somewhere before).

I mean, give a cogent argument. It seems like you can adjust the CMS with the 50/50 pattern amp/sat to hit targets within the space even if you cannot check the full saturation sweep. Now, there is an argument that hue might get it aligned, but messing with the saturation and brightness without the right points and luminance for said points would throw off the color further, so doing 2-pt gray scale and possibly the 10/11/20 gray scale NOT for gamma but instead just to tighten the rgb entirely over the gray scale will aide in accuracy and anything else, but specifically saturation and luminance values, would make it worse without having an accurate defined target. It's a pretty good argument.

But just saying don't touch it in DV without more doesn't explain to a reader WHY they may not want to and what risks they can run if they do manipulate it. Also, these pratfalls can be manufacturer specific so that, depending on which manufacturer made your TV, you could encounter different difficulties.
Thanks. I forgot that I could change the saturation to 5 points using the parameter in HCFR. I was stuck at 4 points. Now I could calibrate using the miscellaneous patterns in the current DV files.
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post #1742 of 1765 Old 06-10-2019, 02:45 PM
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@mascior

I see there are P3 in bt.2020 patterns in the suite. I found it best to target rec.709 in a bt.2020 container. Most scenes are within the rec.709 color space. I don't know if Ryan plans on adding these patterns to the suite.
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post #1743 of 1765 Old 06-10-2019, 05:12 PM - Thread Starter
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Thank you all for the feedback and emails regarding our newly released Dolby Vision test pattern suite, greatly appreciated! However, please remember this is the first revision off many to come and that it took over 20+ revisions to get the HDR-10 test pattern suite where it is today. I already have numerous additions in the works for REV_002! Please see below:

- A compete set of 5% test patches that mimic the 10% variations
- BT709 in BT2020 Color Sweep
- BT709 Sat Sweep inside BT2020
- 24 Point MCD Original ColorChecker
- 24 Point Pantone Skin Tones ColorChecker
- 18 Point ChromaPure Skin Tone ColorChecker
- 11 Color Ramps
- Additional Grayscale Sweeps
- Additional Contrast patterns
- 15 HDR Clipping Test Patterns
- 7 Digital Zone Plate Patterns
- 3 Chroma Subsampling Patterns

Also, I would like to implement DV workflows for both ChromaPure and HCFR, along with LightSpace, once Dolby Vision has been fully implemented within each software.

The only other outstanding item that still needs to be addressed is the Codec ID, which is currently set to dvhe. This flag allows for DV playback compatibility across almost all available DV enabled decoders, except Apple and/or iOS devices. In order for playback on devices like the ATV4K or any other Dolby Vision enable Apple product, a "dvh1" Codec ID is necessary. We are currently working on implementing this flag into our MUX and should be available within the next revision for all of our current test patterns.

I will keep everyone updated on the forums. Again, thank you for your continued support!

- Ryan M.
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post #1744 of 1765 Old 06-10-2019, 05:39 PM
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Quote:
Originally Posted by ajc9988 View Post

Why? Give a cogent reason why just the grayscale. Do you believe the company producing your set accurately set DV color space? Or are you referring to people without Spectracal that may not have proper correction of the color space due to software not yet supporting it officially? Or are you getting at it may not accurately say how to adjust the saturation and brightness within the format due to YCbCr being stretched to the RGB full in the DV standard (not a perfect explanation of what is going on AT ALL with DV, but an explanation I read somewhere before).

I mean, give a cogent argument. It seems like you can adjust the CMS with the 50/50 pattern amp/sat to hit targets within the space even if you cannot check the full saturation sweep. Now, there is an argument that hue might get it aligned, but messing with the saturation and brightness without the right points and luminance for said points would throw off the color further, so doing 2-pt gray scale and possibly the 10/11/20 gray scale NOT for gamma but instead just to tighten the rgb entirely over the gray scale will aide in accuracy and anything else, but specifically saturation and luminance values, would make it worse without having an accurate defined target. It's a pretty good argument.

But just saying don't touch it in DV without more doesn't explain to a reader WHY they may not want to and what risks they can run if they do manipulate it. Also, these pratfalls can be manufacturer specific so that, depending on which manufacturer made your TV, you could encounter different difficulties.
The way I understand it on the LG specifically, as per the dolby vision process, when you generate new configuration files for your specific set, WRGBYCM is read during the creation process after the gray scale calibration is done and the results are written to the file which is then uploaded to the set. Dolby then updates their 3D LUT information dynamically during playback based on the meta-data. I've found the CMS to be very accurate when validating with this process. Different sets have different processes to calibrate DV but for the 2018 and newer LGs, the CalMAN DV workflow process works the best and from my experience gives the most consistent results.
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post #1745 of 1765 Old 06-10-2019, 07:18 PM
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The way I understand it on the LG specifically, as per the dolby vision process, when you generate new configuration files for your specific set, WRGBYCM is read during the creation process after the gray scale calibration is done and the results are written to the file which is then uploaded to the set. Dolby then updates their 3D LUT information dynamically during playback based on the meta-data. I've found the CMS to be very accurate when validating with this process. Different sets have different processes to calibrate DV but for the 2018 and newer LGs, the CalMAN DV workflow process works the best and from my experience gives the most consistent results.
Thank you for the explanation. Explaining to people why one way is preferred over another helps to prevent the follow ups.

I forgot that LG was one that specifically did the upload profile that is created in Calman, which of course I would recommend an updated 3D LUT to a CMS correction.

And I am not arguing that CalMAN does not. Portrait Display/Spectracal have been working closely with Dolby and manufacturers on Dolby Vision (not to say others have not). But, truly, CalMAN is leading in the DV calibration space, if not the space overall.

But, truly, thank you for getting back with that response.
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post #1746 of 1765 Old 06-10-2019, 09:32 PM
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So, first, it depends on which software suite you are using for calibration. I primarily use HCFR, but if you use chromapure, spectracal, or light illusion, there are going to be some differences.

Next, are you talking about HDR10 generally and the PQ EOTF thereof, or Dolby Vision. As was warned, although DV and HDR10 use the same PQ EOTF curve, different display manufacturers may implement it in such a way that you cannot easily do DV the same way of doing HDR10. My Vizio P50-C1 is an example of that. That is the reason I'll eventually be purchasing the Spectracal Home product, but since my next sets will be either Vizio or TCL with current offerings and pricing, I'm holding out until they put out an autocal version for one of those manufacturers (the TCL X10, for example, uses a 17x17x17 3D LUT autocal feature, but isn't released until around September).

So the following will describe my HDR-10 workflow, not DV workflow because I still have not discovered a good way to do it with the freeware software available (if possible, support your developers for software, patterns like R. Masciola's, R.Pi generator, or Ted's Lightspace if going with those options, etc.), but this may work for DV depending how your TV mfrs implemented DV.

1) Set the Backlight.
To do this, you first need to do a reading of your black and 100% white to see what you are working with. If you are under a peak white of 465cd/m^2 with a roll-off implemented, then you should calculate what your diffuse white value should be, which roughly translates to where the 50% gray pattern should be set for nits. For HCFR, this adjusts the luminance curve. You may also want to just run the entire gray scale to figure out whether the manufacturer implements a BT.2390 roll-off at the near white. That is important to understand if it clips and where, which can effect the diffuse white value, which really only comes in if a roll-off is employed.

After you know if the roll-off is implemented and have the diffuse white value, which roughly sets the 50% gray value, you then put up the 50% gray pattern and adjust the backlight until the Y value (xyY calibration) matches the calculated 50% value (on many sets with lower nit values, raising the backlight value will not change the peak brightness. If yours does not change that value, it will move the curve inside of that by changing backlight, so lining up the 50% gray on brightness should help get it close to where it needs to be. This can vary by set, so try to verify how your manufacturer has implemented their controls on the set.).

2) use the patterns to set your brightness and contrast values. Then use the flashing boxes patterns, if your TV employs a color only mode (like blue only mode or red only mode, etc.), to set the color value.
Sometimes you cannot set these perfectly with HDR. Just try your best with what you know on SDR. Many choose Blue over red or green only mode for numerous reasons which will not be discussed here. You could even check the values and select the color with the highest value on color. This is setting chroma, which is related to saturation, but distinct from it. Tom Huffman discussed this a bit in his guide in this forum.

3) Set the grayscale.
First, start with the offset and gain values to try to lower the dE as low as possible. I personally use dICtCp error value, but many use the dECIE76 for gray scale and dECIE2000 values for colors. That really is a preference, but Calman is mentioning that dITP/dICtCp 720 is what they are going with on HDR. I prefer the look I achieve with that even on SDR. But pick your poison, so to speak.

I like to run gray scale sweeps rather than just doing 30/80 or 30/100 for this, then monitoring the RGB delta without gamma on the entire sweep. This allows me to analyze how the offset or gain is effecting the entire scale, allowing to get the RGB dE as low as possible before moving on. Many recommend trying to minimize any increase on the offset values as it may change the black value, including raising the number of nits there. Be aware of the limits of your colorimeter on reading near black levels as well to know where it may be less accurate. For gain, playing with the green value can change the contrast on some displays, so be careful there as well, as you can often just change the red and blue values to balance the gain without running that risk.

Once you have the offset and gain set, then you can move on to adjusting the gray scale with the 10/11/20 point adjustments by including gamma in the calculation. Some manufacturers set the adjustments within the scale that they work with, so you may have to figure out what the percentage on the TV adjustment pairs up with which pattern you are displaying. You might have the 50% TV value match with the 55% gray pattern, etc. So figuring out which value matches which pattern is key (or if it spans two patterns, trying to balance the setting versus the dE value on the two patterns). This can be the most infuriating and time consuming at first. Once you know the set, you can jump in relatively quickly.

4) Set the CMS values for the color, often HSV/HSB values.
Depending on how much gamut coverage you have, this will vary. The wider the supported gamut, the easier this is to set, obviously. This is why, for the most part, you can just use the 50%amp/50%sat patterns, which are around 100 cd/m^2, to set roughly where the color would be similarly to how you set up SDR using 100%amp/100%sat, except you won't have the steps in between if you use sat sweeps to set it. You will want to get the 50% patterns and 25% patterns more on point than worrying about the higher values as this is where the accuracy will matter a bit more, but if your set can support the full values for DCI P3 gamut, up to 90% REC 2020 on top end flagships potentially on some sets, then you will want to try to get it accurately set on the sat sweeps across all percentages as much as possible (good practice anyways). As R. Masciola pointed out in one of his manuals, I think the DV manual, getting the xy coordinates correct is more important than matching the Y luminance value, so if you have to give somewhere, give on that.

You may find you have to make some tradeoffs. It happens.

5) Go back and verify the earlier settings are still good. You may need to change some of the 10/11/20 point adjustments for gamma after making changes to the color CMS. If so, then double check the CMS doesn't need some extra tweaks after that if you changed anything.

So, it is roughly similar to that of SDR calibration for HDR, to a degree. More things to watch for, but not so many that it should be insurmountable. DV does not always follow the above. It should be close, but not always and will vary by implementation by the manufacturer, as well as limitations of your TV set. You also need to watch to make sure the HDR you are setting has activated with the pattern being displayed before taking the measurement, which means there may be a delay between selecting the pattern and when the set kicks in for HDR to then measure, which can vary by set.

The brighter your set's top value is (meaning nits or cd/m^2), the easier it should be for getting the values set, same with wider supported gamut values.



This isn't a perfect explanation, but should give you a rough idea of calibrating HDR. HLG is much simpler, as it follows more closely SDR calibration. For my Vizio P50-C1, it seemed the CMS values were shared between HDR-10 and HLG, so I stuck with my settings for HDR-10 calibration, then just worked within that to set the more global settings of backlight, brightness, contrast, color, tint, sharpness to get it right, which the grayscale tracked really well in regards to RGB balance by using the HDR-10 settings, and did decent on the gamma value, so no real complaints. That can vary by manufacturer though and may be separate CMS controls for each depending on your set.

Hope this helps you guys somewhat.

Edit: and if anyone with more experience wants to jump in and correct anything I've described above, please do so. This is speaking from my current understanding of HDR calibration, which may not be representative of the industry at large or may be inaccurate compared to someone who calibrates for a living or is more engrossed in the content of color theory than I am.
Thanks for a great post. Still trying to get my head around it but certainly helps (not withstanding the arguments that followed )
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post #1747 of 1765 Old 06-11-2019, 09:19 AM
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Thank you all for the feedback and emails regarding our newly released Dolby Vision test pattern suite, greatly appreciated! However, please remember this is the first revision off many to come and that it took over 20+ revisions to get the HDR-10 test pattern suite where it is today. I already have numerous additions in the works for REV_002! Please see below:

- A compete set of 5% test patches that mimic the 10% variations
- BT709 in BT2020 Color Sweep
- BT709 Sat Sweep inside BT2020
- 24 Point MCD Original ColorChecker
- 24 Point Pantone Skin Tones ColorChecker
- 18 Point ChromaPure Skin Tone ColorChecker
- 11 Color Ramps
- Additional Grayscale Sweeps
- Additional Contrast patterns
- 15 HDR Clipping Test Patterns
- 7 Digital Zone Plate Patterns
- 3 Chroma Subsampling Patterns

Also, I would like to implement DV workflows for both ChromaPure and HCFR, along with LightSpace, once Dolby Vision has been fully implemented within each software.

The only other outstanding item that still needs to be addressed is the Codec ID, which is currently set to dvhe. This flag allows for DV playback compatibility across almost all available DV enabled decoders, except Apple and/or iOS devices. In order for playback on devices like the ATV4K or any other Dolby Vision enable Apple product, a "dvh1" Codec ID is necessary. We are currently working on implementing this flag into our MUX and should be available within the next revision for all of our current test patterns.

I will keep everyone updated on the forums. Again, thank you for your continued support!

- Ryan M.
Wow, that's amazing progress on the DV front. Can't wait for the other work flows. Excellent!
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post #1748 of 1765 Old 06-13-2019, 05:03 AM
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Thanks for a great post. Still trying to get my head around it but certainly helps (not withstanding the arguments that followed )

I have no ideas what is he talking about sadly Too many conflicting information. Someone told me I cant adjust contrast/brightness/
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post #1749 of 1765 Old 06-13-2019, 05:20 AM
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Someone told me I cant adjust contrast/brightness/
If you mean in HDR, that is correct. There are a couple of reasons for this. The first is that the current ST2084 luminance curve for HDR is absolute. That means, for instance, that 100% is always intended to be 10,000 nits. It isn't "suggested", as SDR values are. Secondly, because current displays cannot reach either 10,000 nits nor the full Bt2020 gamut, they have to tone map all values above those that they can do. The tone mapping for each display is based on default values for contrast and brightness set by the manufacturer. Change either of those, and the tone mapping is invalid.
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If you mean in HDR, that is correct. There are a couple of reasons for this. The first is that the current ST2084 luminance curve for HDR is absolute. That means, for instance, that 100% is always intended to be 10,000 nits. It isn't "suggested", as SDR values are. Secondly, because current displays cannot reach either 10,000 nits nor the full Bt2020 gamut, they have to tone map all values above those that they can do. The tone mapping for each display is based on default values for contrast and brightness set by the manufacturer. Change either of those, and the tone mapping is invalid.
By that same reasoning, changing the CMS positions of the colors in any way would be invalid because it would effect the tone mapping by the manufacturer, resulting in incorrect display of colors.

So let's bring it back down. Much of HDR content is currently mastered on 4,000 nits, not 10,000 nits. Many displays, instead of trying to tone map ALL THE WAY to 10,000 nits winds up with 4,000 nits as 100% white with the tone mapping within that range up to 4,000. So adjusting the contrast relative to the 4,000 nit value is what I am discussing.

Also, I believe DV is up to 10,000 nits while HDR-10 is 4,000 nits. If you go back and read, I said that is my workflow for HDR-10, meaning what is being adjusted is for the 4,000 nit mastering of HDR-10 content.

Yes, adjusting the contrast CAN effect the tone mapping. You are correct. But there are assumptions and misinformation in your statement as well, unless you are talking about DV content specifically. And even then, currently there are NO 10,000 nit mastering displays, meaning that content mapped between 4,000-10,000 is done on a 4,000 nit mastering display that all are trying to approximate with the tone mapping rather than having some true reference. That means manufacturers may already have incorrect tone mapping for those levels. The question then becomes whether changing the contrast value results in a reduction or exacerbation of the tone map inaccuracies. Many err on the side of caution, following what you have said for leaving well enough alone.

I could make a couple other arguments here, but I'll save those for later.
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By that same reasoning, changing the CMS positions of the colors in any way would be invalid because it would effect the tone mapping by the manufacturer, resulting in incorrect display of colors.

So let's bring it back down. Much of HDR content is currently mastered on 4,000 nits, not 10,000 nits. Many displays, instead of trying to tone map ALL THE WAY to 10,000 nits winds up with 4,000 nits as 100% white with the tone mapping within that range up to 4,000. So adjusting the contrast relative to the 4,000 nit value is what I am discussing.

Also, I believe DV is up to 10,000 nits while HDR-10 is 4,000 nits. If you go back and read, I said that is my workflow for HDR-10, meaning what is being adjusted is for the 4,000 nit mastering of HDR-10 content.

Yes, adjusting the contrast CAN effect the tone mapping. You are correct. But there are assumptions and misinformation in your statement as well, unless you are talking about DV content specifically. And even then, currently there are NO 10,000 nit mastering displays, meaning that content mapped between 4,000-10,000 is done on a 4,000 nit mastering display that all are trying to approximate with the tone mapping rather than having some true reference. That means manufacturers may already have incorrect tone mapping for those levels. The question then becomes whether changing the contrast value results in a reduction or exacerbation of the tone map inaccuracies. Many err on the side of caution, following what you have said for leaving well enough alone.

I could make a couple other arguments here, but I'll save those for later.
I was specifically referring to his post about contrast and brightness, not CMS. HDR-10 is 10,000 nits also.
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I was specifically referring to his post about contrast and brightness, not CMS. HDR-10 is 10,000 nits also.

https://www.rtings.com/tv/learn/hdr10-vs-dolby-vision
Unless you have an update you can point me to?

Edit: if the image is broken for you, do a quick search on peak brightness on that page.
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post #1753 of 1765 Old 06-13-2019, 06:29 AM
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I was specifically referring to his post about contrast and brightness, not CMS. HDR-10 is 10,000 nits also.
No. It isn't. HDR-10 is capped at 4,000nits.
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I was specifically referring to his post about contrast and brightness, not CMS. HDR-10 is 10,000 nits also.
To delve further into the tone mapping issue, I'd like to revisit my discussion on diffuse white value.

With lower peak nit displays, there is a point where the diffuse white cannot reach the ideal point. Personally, to automate the calculation of this value, I open up displaycal, go to the 3D LUT page, and enter the peak brightness of the display in the target peak luminance box, with 2084 roll-off selected. This is not perfect, but gets the diffuse white value in the ball park when implementing a roll-off on sets with peak luminance values below the 465 cd/m^2 value.

After that, in HCFR, I try to manipulate the near white values (edit: in the preferences>references menu for the target value related to the luminance targets) to get the curve to approximate that of the manufacturer. Why? Because you will only be able to change the roll-off curve so much in the manipulation of the 10/11/20 point gamma settings. Those can effect the tone mapping as much as the contrast setting. By finding the curve employed, roughly, you can more closely adjust the brighter side of the white scale to the curve employed with a bit less distortion to the manufacturers tone map, or such is my theory. Not all manufacturers have the same roll-off points and the slope, needless to say matching an idealized roll-off.
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post #1755 of 1765 Old 06-13-2019, 07:04 AM
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Ok, guys. Copied and pasted directly from the rtings page ajc9988 linked to:

"Most Dolby Vision content is currently mastered at 4000 cd/m²; HDR10 and HDR10+ content are mastered at a variety of levels from 1000 to 4000 cd/m² depending on the title.

All three standards cater for images of up to 10,000 cd/m², although no display can currently reach that level. (my emphasis) Therefore there is no real difference between the formats as they both top out at 4000 cd/m²."

They both use ST2084 Perceptual Quantizing, which specifies the luminance levels. Mastering is a separate facet. See:
https://www.lightillusion.com/uhdtv.html
https://www.smpte.org/sites/default/...-2-handout.pdf
Admittedly, the SMPTE info is from 2014, and things may have changed.

@skschatzman said:"No. It isn't. HDR-10 is capped at 4,000nits."
What's your source?
Finally, we are WAYYY off Ryan's topic here. I'm out...
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Originally Posted by Rolls-Royce View Post
Ok, guys. Copied and pasted directly from the rtings page ajc9988 linked to:

"Most Dolby Vision content is currently mastered at 4000 cd/m²; HDR10 and HDR10+ content are mastered at a variety of levels from 1000 to 4000 cd/m² depending on the title.

All three standards cater for images of up to 10,000 cd/m², although no display can currently reach that level. (my emphasis) Therefore there is no real difference between the formats as they both top out at 4000 cd/m²."

They both use ST2084 Perceptual Quantizing, which specifies the luminance levels. Mastering is a separate facet. See:
https://www.lightillusion.com/uhdtv.html
https://www.smpte.org/sites/default/...-2-handout.pdf
Admittedly, the SMPTE info is from 2014, and things may have changed.

@skschatzman said:"No. It isn't. HDR-10 is capped at 4,000nits."
What's your source?
Finally, we are WAYYY off Ryan's topic here. I'm out...
Are you familiar with BT.2390 and roll-off implementation? Have you seen the various roll-offs employed by different manufacturers. Without a roll-off, you have a hard-clip. That is fine, and with that, it has defined values and should follow the 2084 PQ standard without much issue.

But, since you wanted to discuss the effects on tone mapping, BT.2390 effects the high end tone mapping for a roll-off rather than a hard clip.

Also, in regards to Ryan's topic here, the more people understand how to calibrate for HDR, specifically HDR-10 (the namesake of the topic), the better they may use his product in order to calibrate their own sets.
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post #1757 of 1765 Old 06-13-2019, 12:57 PM
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My display clips white below 4000 nits so I lowered contrast 3 points. What I noticed immediately was that a lot of my UHD BluRay content I have, had so much detail crushed, particularly clouds and especially DV content that I ended up doing the same for SDR, but going for a higher video white than 235.
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post #1758 of 1765 Old 06-13-2019, 07:43 PM
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Can one of you kind gents summarise the points above pretty please in terms of what we should and shouldn't do wrt HDR calibration? That's a shed load of information with some conflicting and while I can kinda follow it, it's still very tricky

Pretty, pretty please
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post #1759 of 1765 Old 06-14-2019, 09:35 AM
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Quote:
Originally Posted by mombasa123 View Post
Can one of you kind gents summarise the points above pretty please in terms of what we should and shouldn't do wrt HDR calibration? That's a shed load of information with some conflicting and while I can kinda follow it, it's still very tricky

Pretty, pretty please
1. Argument over changing Contrast/Brightness
Position 1: Changing messes with the mfr tone curve, so don't touch ever
Position 2: Changes to the near white gamma settings with 20 pt also mess with mfr tone curve. So playing with contrast can be done, but also try to adjust the near white slope values so that you can preserve the tone mapping when BT.2390 roll-off is employed (HCFR allows for changing the target slope, not sure if other software vendors allow for this). If no roll-off is employed, match the 2084 spec as best you can on luminance curve.
Position 2 agrees with position 1 that changes to Contrast and Brightness can effect the tone mapping. Just are willing to still change those settings.

2: Argument over supported max luminance:
Position 1: All can reach 10,000 nits
Position 2: HDR-10 is max 4,000 nits, DV is max 10,000 nits.
Both agree: All current mastering displays use 4,000 nits.

I have not seen any arguments on my CMS adjustment part, mostly. I didn't discuss using 2020/P3 over 2020 patterns for calibration accuracy, etc. Although one person asked where those patterns were inside the DV pattern folders. Sorry if I missed some nuance from the discussion, but you asked for a summary.
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post #1760 of 1765 Old 06-14-2019, 01:31 PM
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Quote:
Originally Posted by DisplayCalNoob View Post
My display clips white below 4000 nits so I lowered contrast 3 points. What I noticed immediately was that a lot of my UHD BluRay content I have, had so much detail crushed, particularly clouds and especially DV content that I ended up doing the same for SDR, but going for a higher video white than 235.
@Rolls-Royce

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I personally have noticed only one instance of HDR white clip/crush on my Samsung KS8000, and that was on a distant snowfield in a Samsung SUHD demo.

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@Rolls-Royce , how about in Batman vs. Superman (4knits), in any kryptonite scene? Do you adjust contrast for movies mastered at 4knits?

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Originally Posted by galonzo View Post
@Rolls-Royce , how about in Batman vs. Superman (4knits), in any kryptonite scene? Do you adjust contrast for movies mastered at 4knits?
I do and would, why would you want to clip 4000 nit detail.

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post #1763 of 1765 Old 06-15-2019, 06:45 AM
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Originally Posted by galonzo View Post
@Rolls-Royce , how about in Batman vs. Superman (4knits), in any kryptonite scene? Do you adjust contrast for movies mastered at 4knits?
Nope. I make no adjustments for mastering levels.
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Working with 'Masciola' we have added support for his HDR Disc to LightSpace.
All that was required was to increase max DIP mode to over 1 minute - we have made it 90 seconds.
That way the disc can be played live, and LightSpace will sync with it.

With ColourSpace it will be possible to just take manual readings, and ColourSpace will add them to a final profile data set.
(Not something LightSpace can do without the use of DIP mode.)

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I am trying to calibrate the colors on my "JVC RS540 projector + UB820 SDR2020-mapping combo system" with Calman 2017 HDR10 Calibration Workflow. I am a newbie at that and I have some questions. I set up my projector with a power gamma of 2.4. Now, when I try to adjust the colors (ignoring the brightness component) using the projector's CMS,

1) Which Gamma Formula should I select on the Calman software: ST. 2084 HDR(PQ) or Power 2.4?
2) If I need to select Power 2.4, then, for instance, the Masciola's 50% amp 50% sat yellow pattern has triplets 126,126,105 whereas the Calman claims it's 126,126,86 (undoubtebly, because of the different transfer functions). My question is: can I still use Masciola's patterns to calibrate my colors?

If I'm going about this totally wrong, please direct me to a site that would guide me on how to adjust colors on a projector using the SDR.2020 mapping. Thanks.
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