I have some confusion on the selection of white point when calibrating my monitors. I have always used Native White Point and had good results with my Dell Adobe RGB LCD monitor. A good monitor to print match is important to me. The Native WP on this monitor is around 5700-5800K, which works well with the somewhat neutral to warm papers I print on. I know that an image displayed in Photoshop without an active soft proof will be mapped to monitor white . So, a monitor calibrated to 6500K will display cooler than a monitor calibrated to 5000K. But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR? As I understand it, two "conversions" occur. The first conversion is from the document working space to the printer profile. Then a second conversion occurs from the printer profile numbers to the monitor using RC rendering. If neither Black Ink or Paper White boxes are checked, the simulation on screen ignores paper color and weak blacks. But, if Paper White is checked, shouldn't the paper color and reduced dynamic range appear the same on monitors that are calibrated differently. That doesn't seem to be my experience. I'm assuming that the monitor profiles accurately characterize the current calibration of each monitor. I'd prefer to calibrate to 6500K, but I find my prints always come out too yellow because I am adding more yellow to my image on screen to compensate for the cooler display. When printed, the warmth of most of my papers results in skin tones that are too yellow. What am I missing? Thanks, Lou
On Mar 4, 2019, at 9:39 AM, Louis Dina <lou@loudina.com> wrote:
I have some confusion on the selection of white point when calibrating my monitors.
I have always used Native White Point and had good results with my Dell Adobe RGB LCD monitor. A good monitor to print match is important to me. The Native WP on this monitor is around 5700-5800K, which works well with the somewhat neutral to warm papers I print on.
Native WP is somewhat useful for some displays, such as lower end 6-8 bit per color panels. "Forcing" a WP using some LUT could introduce banding and as such, a Native setting leaves this alone. But that native setting doesn't in any way ensure a visual match to your print when soft proofing.
I know that an image displayed in Photoshop without an active soft proof will be mapped to monitor white . So, a monitor calibrated to 6500K will display cooler than a monitor calibrated to 5000K.
There's an RGB working space and there's a display profile and there's always Display Using Monitor Compensation with the two profiles. Or there's a printer output space and the display, again DUMC.
But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR?
What I do with my SpectraView's is calibrate for a visual match, using WP settings of course, WITH the image set with this paper white mapping ON. These settings are therefore output specific with the soft proof for the printer using paper and ink simulation on.
As I understand it, two "conversions" occur. The first conversion is from the document working space to the printer profile. Then a second conversion occurs from the printer profile numbers to the monitor using RC rendering.
That is my understanding as well.
If neither Black Ink or Paper White boxes are checked, the simulation on screen ignores paper color and weak blacks. But, if Paper White is checked, shouldn't the paper color and reduced dynamic range appear the same on monitors that are calibrated differently.
DR and paper white (color). You really want those settings on or you're viewing a print at a DR that's simply impossible (1000:1 or far more).
That doesn't seem to be my experience. I'm assuming that the monitor profiles accurately characterize the current calibration of each monitor.
The calibration is, in my use, that to produce a match to the soft proof. And I can build multiple calibrations for differing papers thanks to SpectraView.
I'd prefer to calibrate to 6500K, but I find my prints always come out too yellow because I am adding more yellow to my image on screen to compensate for the cooler display. When printed, the warmth of most of my papers results in skin tones that are too yellow.
And that's the issue. It isn't what you prefer, it's what produces a visual match to the paper on-screen. That's why it makes sense to target the calibration for a match. And that match includes paper white. There's a video on my web site that covers all this ("Why are my prints too dark"). Andrew Rodney http://www.digitaldog.net/
Hi Lou, The answer to your question: "But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR?" No, they will not look the same, The paper white simulation is "relative to your monitor white point". EIZO ColorNavigator or X-Rite's i1Profiler's monitor profiling modules offer validation against CMYK standards. At the end of the validation, the measured value of paper white for FOGRA39 verification can be reported to be very close to 95,0, -2. But do not let this measurement mislead you. This is only true "relative" to the monitor white (native or any other monitor white that you have picked) which now serves as the 100, 0, 0 reference. You can set the white point of calibration to any temperature in the 5000 to 6500 K range and after every calibration/profiling round the validation may tell you that Patch # 63 (paper white) of UGRA/FOGRA Media Wedge v3 is measuring within a deltaE(2000) less than 1 against 95, 0, -2. But in absolute terms the simulated color on the screen is different every time. In the verification module of DisplayCAL, you can switch "Simulate whitepoint" and "Relative to display profile whitepoint" on or off to measure the actual color of the monitor white. Soft proofing heavily relies on the adaptive capability of the eye. Just try to find the color temperature that is right for you using a proper light box and the print substrate that you frequently use. And this pick will only work for your eyes. Recently, I have calibrated a monitor at 100 K increments in the 4800 to 6500 K range. Next to it was a desktop viewer with fresh lamps illuminating a sheet of FOGRA39 compatible print stock. The whole screen was simulating FOGRA39 paper white in Photoshop. Going through the profiles one after the other, my colleagues have asked 6 different people which color temperature gave them the best match. No two picked the same temperature. As the monitors create the illusion of white by using 3 narrow band emissions at blue, green and red regions of the visible spectrum. One monitor, as a light source, may have a CRI value of 37 (3 very narrow band emission) and the other may have a CRI value of 93 with no gaps in the spectral emission curve. In fact, I repeated the test with this high CRI monitor and more people agreed on the color temperature that gave the best match. Monitors are very different from each other, you may find very different display panels in monitors of a certain brand. Best regards, -------------------------------------------------------- Refik Telhan, EE B.Sc. Light and Color Management Consultancy Aydogdu Sokak 12A, Tarabya Mahallesi Sariyer, 34457, Istanbul, Turkey Mobile: + (90) (532) 426 21 87 -------------------------------------------------------- On 04.03.2019 19:40, "colorsync-users on behalf of Louis Dina" <colorsync-users-bounces+rtelhan=icloud.com@lists.apple.com on behalf of lou@loudina.com> wrote: I have some confusion on the selection of white point when calibrating my monitors. I have always used Native White Point and had good results with my Dell Adobe RGB LCD monitor. A good monitor to print match is important to me. The Native WP on this monitor is around 5700-5800K, which works well with the somewhat neutral to warm papers I print on. I know that an image displayed in Photoshop without an active soft proof will be mapped to monitor white . So, a monitor calibrated to 6500K will display cooler than a monitor calibrated to 5000K. But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR? As I understand it, two "conversions" occur. The first conversion is from the document working space to the printer profile. Then a second conversion occurs from the printer profile numbers to the monitor using RC rendering. If neither Black Ink or Paper White boxes are checked, the simulation on screen ignores paper color and weak blacks. But, if Paper White is checked, shouldn't the paper color and reduced dynamic range appear the same on monitors that are calibrated differently. That doesn't seem to be my experience. I'm assuming that the monitor profiles accurately characterize the current calibration of each monitor. I'd prefer to calibrate to 6500K, but I find my prints always come out too yellow because I am adding more yellow to my image on screen to compensate for the cooler display. When printed, the warmth of most of my papers results in skin tones that are too yellow. What am I missing? Thanks, Lou _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/rtelhan%40icloud.com This email sent to rtelhan@icloud.com
Hi Lou. I can confirm what Refik is saying from having made on-screen measurements• using an i1pro and Spectrashop a few years back. Regards Peter Miles *A few years back I wanted to clarify in my mind the same question Lou asked. So I measured the on-screen colour of a soft proof in photoshop when the 'simulate paper color’ was on. I compared that to measurements I made of the display white point. I did this on a profiled Eizo at a 3 different white point settings . From the measurements it was clear that the on-screen colour of the soft-proof (with ‘Simulate Paper Color’ on) was different for each display white point used. And from comparing the ab plots in Spectrashop it was also clear that the on-screen colour of the soft-proof (with ‘Simulate Paper Color' on) was being shifted ‘relative' to the white point of the display. On 5/03/2019, at 10:12 AM, Refik Telhan <rtelhan@icloud.com<mailto:rtelhan@icloud.com>> wrote: Hi Lou, The answer to your question: “….But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR?" No, they will not look the same, The paper white simulation is "relative to your monitor white point".
Thanks to everyone for your responses about monitor calibration. They all helped. Refik... The first paragraph of your response helped me clear up my confusion (I think!). I guess I always thought of Lab colors as absolute. So, when I saw 100/0/0 Lab, to me that meant dead neutral. But, thinking about it more, I realize that was probably my biggest confusion. An Adobe RGB image with a pure white patch reads 255/255/255 RGB and 100/0/0 Lab in the Info Palette, and within that color space, it is dead neutral. But that will only "appear" dead neutral on my monitor if it is calibrated so white displays as dead neutral. If calibrated to 7500K, 255/255/255 and 100/0/0 will display as bluish white, and if calibrated to 5000K, the same 255/255/255 and 100/0/0 will appear warm white. Checking Paper White uses the monitor's current white point as its baseline. I thought all profiles (monitor, print, working spaces) included white point information and I figured all conversions would take this into account. Somehow, I figured the CMM would see a 6500K monitor as being a cool white and normalize it to dead neutral during soft proofing (when Paper white is checked), then show the paper color relative to dead neutral. Apparently, that is not the case, which is clear from my experimentation. So, at least on my system, my viewing lights, my custom printer profiles, and most of my printing papers, I find that a monitor WP of about 5800K, +/- 200K, gives me a good monitor soft proof to print match (with Paper white checked). There's probably a reason why our CMM can't correct for the monitor white point when soft proofing. It seems to be it would be nice to calibrate to 6500K for the internet, and be able to see accurate soft proofs on screen by comparing white points in all the profiles in the chain. Then, 6500K would work for all papers. But, maybe not. At any rate, I now know that any correction for Paper White is relative to the calibrated WP of the monitor. Thanks, Lou On Mon, Mar 4, 2019 at 3:12 PM Refik Telhan <rtelhan@icloud.com> wrote:
Hi Lou,
The answer to your question:
"But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR?"
No, they will not look the same, The paper white simulation is "relative to your monitor white point". EIZO ColorNavigator or X-Rite's i1Profiler's monitor profiling modules offer validation against CMYK standards. At the end of the validation, the measured value of paper white for FOGRA39 verification can be reported to be very close to 95,0, -2. But do not let this measurement mislead you. This is only true "relative" to the monitor white (native or any other monitor white that you have picked) which now serves as the 100, 0, 0 reference. You can set the white point of calibration to any temperature in the 5000 to 6500 K range and after every calibration/profiling round the validation may tell you that Patch # 63 (paper white) of UGRA/FOGRA Media Wedge v3 is measuring within a deltaE(2000) less than 1 against 95, 0, -2. But in absolute terms the simulated color on the screen is different every time. In the verification module of DisplayCAL, you can switch "Simulate whitepoint" and "Relative to display profile whitepoint" on or off to measure the actual color of the monitor white.
Soft proofing heavily relies on the adaptive capability of the eye. Just try to find the color temperature that is right for you using a proper light box and the print substrate that you frequently use. And this pick will only work for your eyes. Recently, I have calibrated a monitor at 100 K increments in the 4800 to 6500 K range. Next to it was a desktop viewer with fresh lamps illuminating a sheet of FOGRA39 compatible print stock. The whole screen was simulating FOGRA39 paper white in Photoshop. Going through the profiles one after the other, my colleagues have asked 6 different people which color temperature gave them the best match. No two picked the same temperature. As the monitors create the illusion of white by using 3 narrow band emissions at blue, green and red regions of the visible spectrum. One monitor, as a light source, may have a CRI value of 37 (3 very narrow band emission) and the other may have a CRI value of 93 with no gaps in the spectral emission curve. In fact, I repeated the test with this high CRI monitor and more people agreed on the color temperature that gave the best match. Monitors are very different from each other, you may find very different display panels in monitors of a certain brand.
Best regards,
-------------------------------------------------------- Refik Telhan, EE B.Sc.
Light and Color Management Consultancy
Aydogdu Sokak 12A, Tarabya Mahallesi Sariyer, 34457, Istanbul, Turkey
Mobile: + (90) (532) 426 21 87 --------------------------------------------------------
On 04.03.2019 19:40, "colorsync-users on behalf of Louis Dina" <colorsync-users-bounces+rtelhan=icloud.com@lists.apple.com on behalf of lou@loudina.com> wrote:
I have some confusion on the selection of white point when calibrating my monitors.
I have always used Native White Point and had good results with my Dell Adobe RGB LCD monitor. A good monitor to print match is important to me. The Native WP on this monitor is around 5700-5800K, which works well with the somewhat neutral to warm papers I print on.
I know that an image displayed in Photoshop without an active soft proof will be mapped to monitor white . So, a monitor calibrated to 6500K will display cooler than a monitor calibrated to 5000K.
But, when you soft proof, with the Paper White box checked, shouldn't the soft proof look the same on a 5000K and a 6500K MONITOR? As I understand it, two "conversions" occur. The first conversion is from the document working space to the printer profile. Then a second conversion occurs from the printer profile numbers to the monitor using RC rendering. If neither Black Ink or Paper White boxes are checked, the simulation on screen ignores paper color and weak blacks. But, if Paper White is checked, shouldn't the paper color and reduced dynamic range appear the same on monitors that are calibrated differently. That doesn't seem to be my experience. I'm assuming that the monitor profiles accurately characterize the current calibration of each monitor.
I'd prefer to calibrate to 6500K, but I find my prints always come out too yellow because I am adding more yellow to my image on screen to compensate for the cooler display. When printed, the warmth of most of my papers results in skin tones that are too yellow.
What am I missing?
Thanks, Lou _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users@lists.apple.com) Help/Unsubscribe/Update your Subscription:
https://lists.apple.com/mailman/options/colorsync-users/rtelhan%40icloud.com
This email sent to rtelhan@icloud.com
participants (5)
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Andrew Rodney
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John Gnaegy
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Louis Dina
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Miles, Peter
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Refik Telhan