January 2020 - colorsync-users

RE: 1 billion colors
by graxx＠videotron.ca 06 Jan '20

06 Jan '20

Is anyone able to discriminate between the 16.7 million colors in this 24-bit RGB image? https://1drv.ms/u/s!AkD78CVR1NBqko8JmNRgIB2qvxz-iA?e=7il8Xk Be honest. / Roger

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Re: 1 billion colors
by graxx＠videotron.ca 06 Jan '20

06 Jan '20

... Took the liberty to change the title of the thread. Out of 16.7 million or 1.07 billion colors, I suspect there are "redundant" combinations? Such that RGB = A,B,C or G,H,K come out to be the "same" color, visually? I think it is NOT unintuitive to think that this is in fact very likely, David? The same could be said of 1 billion colors, there ought to be combinations of colors that come out to be the same visually? Although I don't know anyone who ever tested this, extensively. And if I may, I don't know to what extent can a person with normal color vision be expected to be able to discriminate among 16.7 million colors? / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of David Scharf via colorsync-users Sent: Monday, January 6, 2020 12:13 AM To: colorsync-users(a)lists.apple.com; Andrew Rodney <andrew(a)digitaldog.net> Cc: David Scharf <electronman(a)roadrunner.com> Subject: Re: NEC PA271Q "Native" chromaticities So you're saying that when these "color" numbers come up that we will see only gray? Nah, I don't think so. I think that most of us understand the Physics and and perceptive aspects of color. Perhaps you mean that these "invisible" colors do not exist as perceptually different from other colors close by in number? DAVID SCHARF PHOTOGRAPHY *DAVID SCHARF* On 1/5/20 5:26 PM, Andrew Rodney via colorsync-users wrote: > I'm talking both. > > Color, is a perceptual property. So if you can't see it it's not a color. Color is not a particular wavelength of light. It is a cognitive perception, the excitation of photoreceptors followed by retinal processing and ending in the our visual cortex, within our brains. Sounds like biology to me.... As such, colors are defined based on perceptual experiments. > > Fairchild's "Color Appearance Models". Page 1! > "Like beauty, color is in the eye of the beholder. For as long as human scientific inquiry has been recorded, the nature of color perception has been a topic of great interest. Despite tremendous evolution of technology,fundamental issues of color perception remain unanswered. Many scientific attempts to explain color rely purely on the physical nature of light and objects. However, without the human observer, there is no color". > Further on the same page: > "It is common to say that certain wavelengths of light, or certain objects are a give color. This is an attempt to relegate color to the purely physical domain. It is more correct to state those stimuli are perceived to be a certain color when viewed under specific conditions". > > Page 1 paragraph 2 of Digital Color Management by Giorgianni and Madden: > "But color itself is a perception and perceptions only exist in the mind". > > Page 11 of The GATF Practical guide to Color Management: > "Although extensive research has been conducted, we still not completely understand what happens in the brain when we "see" color. The visual sensation known as color occurs when light excites photoreceptors in the eye called cone cells". > > Page 75 of Understanding Color Management by Sharma: > "Color is an impression that we form in our brains". > > >> On Jan 5, 2020, at 5:57 PM, David Scharf <electronman(a)roadrunner.com> wrote: >> >> Hi Andrew, >> >> I think your talkin color science and engineering and I'm talkin biology. Inability to differentiate close colors does not mean their non-existence or imperceptibility. That's not silly, its actual! >> >> DAVID SCHARF >> http://www.electronmicro.com <http://www.electronmicro.com/> > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > colorsync-users mailing list (colorsync-users(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/colorsync-users/david%40scharf > photo.com > > This email sent to david(a)scharfphoto.com > _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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RE: 1 billion colors
by graxx＠videotron.ca 06 Jan '20

06 Jan '20

Wire, You wrote : > However an RGB / YUV display that processes 1 billion colors on its interface may reasonably be > expected to produce 1 billion quantifiably different stimuli on its face That's the whole point of the thread, isn't it? I remain skeptical. Stick with 16.7 million colors for a moment : can you point to any article that ever documented this? / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of Wire ~ via colorsync-users Sent: Monday, January 6, 2020 7:57 AM To: 'colorsync-users?lists.apple.com' List <colorsync-users(a)lists.apple.com> Subject: Re: 1 billion colors This convo is on the edge of nonsense. OMG Do some color numbers in some color space produce indistinguishable stimulus? Consider a color-blind viewer. Or close your eyes. The point of the extra bits in context could not be more simple: 8 bpc color rendering can have problems with quantization noise. As dynamic range is expanding in newer gear pertaining to UHD TV HDR, this limit is encroached. A couple more bits per channel were added to standard display data formats. Just like high bpc support was added to Photoshop. Marketeers looked at old-school Windows / Mac color control panel "hundreds, thousands, true (millions)" which always just counted the number of unique numerical combinations and disregarded important details like indexed color (the original LUT) and kept rolling with it. So what? To know anything about the CIE tristimulus model, is to know it's about a math that connects a physics of light to an idealized observer using statistical sampling of perceptible difference across a human population. The subjectivity of the qualia is subsumed by the model. It works because our visual systems work a lot alike, just like most of us have arms and legs with fingers and toes, but not wings. To note that Pro Photo RGB has some values that don't lie within the CIE spectrum locus is fine. In integer Lab lots of values don't fall into the spectrum locus. However an RGB / YUV display that processes 1 billion colors on its interface may reasonably be expected to produce 1 billion quantifiably different stimuli on its face that lie within its CIE gamut volume, because of the way the data format works. We all know (I hope) that how many of these are needed for any given application is a subjective matter. If you only present grayscale images, maybe only 0.00001% of them aren needed. If you prefer sepia, maybe more, etc. The marketing claim is fair: there are applications where the full range of input values are known to be useful and applicable. Don't get lost in the noodling over semantics of the term color. If you want to freak out about it, consider the word "time" and linguistic tense. Then observe a Zen moment of silent contemplation.

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RE: Dell UP2516D
by graxx＠videotron.ca 05 Jan '20

05 Jan '20

Wire, Thanks for following up with these new analytical reports. The performance is very good. It may be possible to do better but it's not bad at all. Please excuse my ignorance but where does the Display profile "Luminance" comes from? Is that in the AdobeRGB (1998) specs itself, that the calibrated Luminance ought to be 144.2 cd/m2? Whereas, on your Dell, with your DTP94 (w/i1cmx) the measured Luminance is 113.9? I guess you get 113.9 as a consequence of having selected the AdobeRGB Preset on your monitor? I will have to read up on that.... Also, why do they have a line which reads : "Assumed target whitepoint: 6700K daylight, xy 0.3097 0.326 (XYZ 94.97 100 111.73)", where could this value come from? More reading.... That would seem to suggest some kind of "native white point" option. / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of Wire ~ via colorsync-users Sent: Sunday, January 5, 2020 3:52 PM To: colorsync-users(a)lists.apple.com Subject: Re: Dell UP2516D Not sure how the DCal reports I've shared will manifest when accessed? They're self-contained html with some local active form elements to allow a menu. https://drive.google.com/drive/mobile/folders/1bxq64ybCYUxh4USCHPG99Q8Bp3-iG oV1/1DSpUzIAgxsiG8qi8FKr2uJ5_P4MNmTKu The Adobe RGB measurement report plot shows worse gamma tracking than sRGB, but don't know why. I don't know how to read that graph. Also are some options in DCal to adjust the way it handles blacks when making a report, I need to look into it... _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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Dell UP2516D
by Wire ~ 05 Jan '20

05 Jan '20

Whoops, it's UP2516D, not 2916 Yes max brightness is slightly reduced by using calibrated modes compared to native, as is max gamut. Slightly. The great guys at DisplayCal have included a DTP94+UP2516D colorimeter correction file referenced to i1pro. Working with this I'm finding a slight change in white point and good repeatability. This may let me punt on getting an i1 for now. Fantastic!! I turned off uniformity compensation, pre-cal'd white and dark grey using DCal's pre-measurement feature, then re-profiled. This produces a perfectly matched pair that look right in every way I know how to judge, plus per above full native mode opens up brightness and gamut a smidge as compared to using the display's 6500 preset. And uniformity looks very acceptable. dE Max is still hitting 2.x, dE RMS 1. I added another iphone screen grab which nicely shows off the matching. I'm super stoked. Re Dell SDK I saw that too and have the same questions as you. There's no software in the box, as you would expect in this mature age of the webz... Re built-in LUTs: Wasn't Graeme of ArgyllCMS posting here a week ago that video nerds take this feature for granted 'cause lots of their tools are not color managed—not the way DTP folks think about it. Like they will have a whole pipeline that assumes 709 or SLog or who-knows-what and give the display whatever personality needed via its LUT? Also there's the MadVR stuff that's a renderer for high-end home theater. I use Kodi media viewier (was Xbox Media Center back in day) and it has support for loading a 3D LUT profile. Again this is stuff that's been in video for a decade or more is now being commodified. I'll run a DisplayCal verification report on the built-in Adobe RGB mode. It will look at more color and we'll see... On Sat, Jan 4, 2020 at 16:40 Roger Breton via colorsync-users < colorsync-users(a)lists.apple.com> wrote: > In fairness, I had to change the title of the thread... > > The numbers in the report are good, Wire, and thank you for posting. I've > plough through the User Manual on Dell's web site but could not find any > references to the existence of "hardware LUTs"? I was looking for this > feature in view of the excellent Gray-Scale Tracking behavior. As for the > 'Gamut' tests, sRGB/AdobeRGB support, I don't think anyone could dispute > the < 2 Avg dE value presented in the calibration report. But I'd like to > see a comparison on more than a handful of color values? Perhaps DispCal > can crank out a more "extensive" report than Dell but it's worth nothing > the manufacturer's claim is based on a set 32 color samples (8 GS values + > 4 Red + 4 Green + 4 Blue + 4 Y + 4 C + 4 M), according to my reading of the > report. I'll bet the results based on a broader sample set will still be > very acceptable, Wire? (Didn't you already tested this with DispCal?) The > gray levels graph suggest that the unit is plenty gamma-corrected, out of > the box. The Brightness Uniformity figures are hard to resist / beat, > though? Same as the Color Uniformity figures? I mean, those kinds of > differences are minuscule to me -- almost too good to be true, but that's > probably the state of good, quality displays these days 😊 > > Have you found that, when using one of the Presets (sRGB/AdobeRGB, > whatever), that the display Luminance changes accordingly? I read something > to that effect .... > > Last but not least, this statement eluded me before: > > > User-enabled adjustments: Dell's software development kit, or SDK, > enables > > customers with a proprietary colour solution to customize Dell > UltraSharp > > Monitors with their preferred specifications. You can also fine-tune > colour > > parameters, including RGBCMY saturation,RGBCMY hue, RGB and RGB offset. > > It surely does not mean that there's a CD in the box, somewhere, > containing an "SDK" for you or the casual color management hobbyist to get > into programming the display directly? > > / Roger > > -----Original Message----- > From: colorsync-users <colorsync-users-bounces+graxx= > videotron.ca(a)lists.apple.com> On Behalf Of Wire ~ via colorsync-users > Sent: January 4, 2020 5:58 PM > Cc: 'colorsync-users?lists.apple.com' List < > colorsync-users(a)lists.apple.com> > Subject: Re: NEC PA271Q "Native" chromaticities > > On Sat, Jan 4, 2020 at 2:44 PM Roger Breton via colorsync-users < > colorsync-users(a)lists.apple.com> wrote: > > > Wire, > > Do you mind posting a scan (photo) of that certificate? > > > > I added the report: > > https://drive.google.com/open?id=1DSpUzIAgxsiG8qi8FKr2uJ5_P4MNmTKu > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > colorsync-users mailing list (colorsync-users(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > > https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca > > This email sent to graxx(a)videotron.ca > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > colorsync-users mailing list (colorsync-users(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > > https://lists.apple.com/mailman/options/colorsync-users/wire%40lexiphanicis… > > This email sent to wire(a)lexiphanicism.com >

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RE: Dell UP2516D
by graxx＠videotron.ca 05 Jan '20

05 Jan '20

Wire, You wrote: > Re built-in LUTs: Wasn't Graeme of ArgyllCMS posting here a week ago > that video nerds take this feature for granted 'cause lots of their > tools are not color managed—not the way DTP folks think about it. The only reason I brought this up is because of "traditional" discussions, here and elsewhere, about 8-bit calibrations which, as far as I can remember, was always a subject of contention -- can't remember exactly why? Other than "taking away" levels of colors, I guess. Whereas the part of a "monitor LUT" that interests me are those that reside in its memory (eeprom), nothing to do, in my mind, with the "3D LUTs" used in "video effects", for those who seek the "look" of Fujichrome or Extachrome films, etc. Now things maybe very different now, especially in the context of 10-bit frame buffers. But I may be wrong... Ever fascinating stuff. / Roger

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C
by Mike Kersley 05 Jan '20

05 Jan '20

Sent from my iPhone

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Dell UP2916D
by graxx＠videotron.ca 05 Jan '20

05 Jan '20

In fairness, I had to change the title of the thread... The numbers in the report are good, Wire, and thank you for posting. I've plough through the User Manual on Dell's web site but could not find any references to the existence of "hardware LUTs"? I was looking for this feature in view of the excellent Gray-Scale Tracking behavior. As for the 'Gamut' tests, sRGB/AdobeRGB support, I don't think anyone could dispute the < 2 Avg dE value presented in the calibration report. But I'd like to see a comparison on more than a handful of color values? Perhaps DispCal can crank out a more "extensive" report than Dell but it's worth nothing the manufacturer's claim is based on a set 32 color samples (8 GS values + 4 Red + 4 Green + 4 Blue + 4 Y + 4 C + 4 M), according to my reading of the report. I'll bet the results based on a broader sample set will still be very acceptable, Wire? (Didn't you already tested this with DispCal?) The gray levels graph suggest that the unit is plenty gamma-corrected, out of the box. The Brightness Uniformity figures are hard to resist / beat, though? Same as the Color Uniformity figures? I mean, those kinds of differences are minuscule to me -- almost too good to be true, but that's probably the state of good, quality displays these days 😊 Have you found that, when using one of the Presets (sRGB/AdobeRGB, whatever), that the display Luminance changes accordingly? I read something to that effect .... Last but not least, this statement eluded me before: > User-enabled adjustments: Dell's software development kit, or SDK, enables > customers with a proprietary colour solution to customize Dell UltraSharp > Monitors with their preferred specifications. You can also fine-tune colour > parameters, including RGBCMY saturation,RGBCMY hue, RGB and RGB offset. It surely does not mean that there's a CD in the box, somewhere, containing an "SDK" for you or the casual color management hobbyist to get into programming the display directly? / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of Wire ~ via colorsync-users Sent: January 4, 2020 5:58 PM Cc: 'colorsync-users?lists.apple.com' List <colorsync-users(a)lists.apple.com> Subject: Re: NEC PA271Q "Native" chromaticities On Sat, Jan 4, 2020 at 2:44 PM Roger Breton via colorsync-users < colorsync-users(a)lists.apple.com> wrote: > Wire, > Do you mind posting a scan (photo) of that certificate? > I added the report: https://drive.google.com/open?id=1DSpUzIAgxsiG8qi8FKr2uJ5_P4MNmTKu _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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RE: NEC PA271Q "Native" chromaticities
by graxx＠videotron.ca 04 Jan '20

04 Jan '20

Wire, Do you mind posting a scan (photo) of that certificate? Seems every 'high-end' monitors comes with some kind of 'certificate' nowadays. My original Eizo sure came with one such (lost the copy a long time ago). As for the NEC? I don't remember. Probably. 1 billion colors... Best / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of edmund ronald via colorsync-users Sent: January 4, 2020 5:29 PM To: Wire ~ <wire(a)lexiphanicism.com> Cc: colorsync-users(a)lists.apple.com Subject: Re: NEC PA271Q "Native" chromaticities I think the Babelcolor author has a tool to measure uniformity and possibly other display properties. I don’t see any reason to doubt a certificate, there are Photo Research radiometers that can map a whole display in one pass, and the fact that there is a certificate would indicate a measurement is part of the production process. Edmund On Sat, Jan 4, 2020 at 9:13 PM Wire ~ via colorsync-users < colorsync-users(a)lists.apple.com> wrote: > Forgive me, I was referring to Dell's claims for consistency of this model. > > A delta-E being a CIE unit of color difference based on a statistical > notion of a discernable color diff. Color guys talk about like audio > and RF guys talk about dB, and video guys talk about IRE > > This model targets content pros. It's about the "P" in UP2516D. > > So my measurements as revealed by DCal made profile is that the Adobe > RGB mode hits Dell's target. > > And Dell supplies a certificate report for each unit showing it meets > their claims. This includes panel uniformity as well as color response. > > You guys here rightly asked—in other so many words—Yeah, but does it > actually do it?! In context of NEC pro gear that has a rep for getting > this stuff right. And at this price point, the query is wise if maybe not fair. > > I'm skeptical too... > > So living on edge of BS as I do I throwing out there a synopsis that > based on what I'm seeing Dell's claim is legit. And I'm hoping for a > contrary persoective 'cause it seems too good to be true ;) > > Re 1 billion colors: HDMI and DP (I thinj) support 10 bit color data > path from graphics to device. 3 x 2^10 is a billion. Not sure what > content can use this? > > On Sat, Jan 4, 2020 at 11:35 Roger Breton via colorsync-users < > colorsync-users(a)lists.apple.com> wrote: > > > > I mean that in Adobe RBB mode, it's not unreasonable to predict > > > that > > Dell > > > hits 2 delta-E conformance across the population. IOW, yes > > > consistency across the face of one panel, and conformance of the > > > population to the standard color space. > > > > Here's a screen capture showing the difference between the Dell > > UP2516 > and > > AdobeRGB: > > > > https://1drv.ms/u/s!AkD78CVR1NBqkoskUPmmGmwKuk7b4Q?e=ldqlgr > > > > It's not bad at all. I don't know if it amounts to 2 DeltaE? But > > it's possible. > > Does DispCal (Argyll) have any tools to test this hypothesis? > > > > We are indeed living in a "golden age" of technology. > > > > / Roger > > > > _______________________________________________ > > Do not post admin requests to the list. They will be ignored. > > colorsync-users mailing list (colorsync-users(a)lists.apple.com) > > Help/Unsubscribe/Update your Subscription: > > > > > https://lists.apple.com/mailman/options/colorsync-users/wire%40lexipha > nicism.com > > > > This email sent to wire(a)lexiphanicism.com > > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > colorsync-users mailing list (colorsync-users(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > > https://lists.apple.com/mailman/options/colorsync-users/edmundronald%4 > 0gmail.com > > This email sent to edmundronald(a)gmail.com > _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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RE: NEC PA271Q "Native" chromaticities
by graxx＠videotron.ca 04 Jan '20

04 Jan '20

10-bit used to be considered the "Holy Grail" of monitor display. Apple was first at the gate and now, it is spreading. Personally, I'm not interested in 10-bit support for the next video standard (HDR10?), I'm interested in 10-bit support in Photoshop and image editing. / Roger -----Original Message----- From: colorsync-users <colorsync-users-bounces+graxx=videotron.ca(a)lists.apple.com> On Behalf Of Wire ~ via colorsync-users Sent: January 4, 2020 5:46 PM To: colorsync-users(a)lists.apple.com Subject: Re: NEC PA271Q "Native" chromaticities 10-bits is about UHD HDR I believe. In other words, it's about how changes in video have caught up and exceeded photography and print. And rather than not being able to see 1 billion colors being a downside, this is in fact it's desirable claim: it's got lower quantization noise so you don't get banding the new gen of super bright HDR capable imaging. Take a look at all the talk about Apple's new Pro XDR Display to see where this all is going. When you do, you'll see the effect UHD TV standards are having. Roger mentioned BT2020 gamut a while ago. It's in the context of that aspiration in which Display P3 can be seen as significant, because the jump to BT2020 is too far. Even if displays that can do it become readily available, the legacy of sRGB is gonna intrude. Over at DCal forums Display P3 is known as sRGB-2020. I see it basically getting a reasonable step up in gamut while not blowing the legacy out of the water, thanks to a better balanced expansion of the primaries than Adobe RGB, and a backwards looking sRGB TRC. But video is the future and it's changing fast the way DTP stuff was changing 20 years ago! _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx(a)videotron.ca

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