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Hello everyone.
Can anyone tell me where I can find the official document/documents on the topic of the display needing a color profile created by a calibrator? Apart from the monitor setup itself. I know my question sounds stupid, but hasn’t the manufacturer already done everything in the display? Needed is links to official documents from various institutions where the standard was adopted that this is necessary.Hello everyone.
Can anyone tell me where I can find the official document/documents on the topic of the display needing a color profile created by a calibrator? Apart from the monitor setup itself. I know my question sounds stupid, but hasn’t the manufacturer already done everything in the display?Display native gamut is not fixed by any standard, just what each technology can give you in each of its flavors. At best manufacturer can provide a nominal gamma, a nominal whitepoint and the XYZ coordinates of RGB primaries. This info is stored in driver’s ICM (Windows) for monitor, privided by manufaturer or in “EDID” info of display. DisplayCAL can read EDID info from display and create such ICM file *IF* (a big if) you assume that monitor behavior matches that info.
“factory calibrated modes” if you trust them (not so accurate) “to some known colorspace” should use as display profile the colorspace they are simulating.
Needed is links to official documents from various institutions where the standard was adopted that this is necessary.
An ICC profile is needed because a display can have an arbitrary colorspace. Hence a color managed app needs to know destination colospace to reencode RGB numbers in an image definen in any other arbitrary colorspace (sRGB, AdobeRGB…)
I understand all of this, to be honest. But I don’t know how to convey the information to this one developer of a photo editing program. He has developed various things for displays himself and believes that the display already has everything you need))
https://foto.ru/forum-posts/14020223 – I’m sorry, but everything there is in Russian.The program is unique in its tools, but it is not compatible with the color management system. The program works with the monitor through windows gdi+. I don’t know what this is. I don’t have enough experience to explain to him that a profile is necessary, although I have already laid everything out on the shelves. I have given him examples. He thinks that a display profile is marketing and nothing more.
You can rely on some open source color management systems, for example
https://www.littlecms.com/The basic pipeline is:
-read JPG/TIFF profile info, if present. If not present you may ask user to asume that it’s sRGB data or other custom profile.
-using profile info translate RGB data in photo to XYZ coordinates (usually PCS coords)
-read using OS api “current display profile” for Screen N.
-reencode (relative whitepoint: rel col or perceptual) XYZ coordinates of each pixel in image previously obtained to RGB data in display colorspace.Little CMS provides all this to you, include it in your app.
When you draw image canvas on screen instead of RGB data stored in JPG/TIFF you translate RGB data from image’s embeded profile (or supposed if missing, like sRGB) to default display profile in OS (like the ones that create DisplayCAL/i1Profiler or the ones provided by monitor anufacturer in driver as “generic native gamut” for each display), using LittleCMS or other CMM or one of your own. But seems wise to first use one of these already built.I don’t have enough experience to explain to him that a profile is necessary, although I have already laid everything out on the shelves. I have given him examples. He thinks that a display profile is marketing and nothing more.
The basic pipeline is:
-read JPG/TIFF profile info, if present. If not present you may ask user to asume that it’s sRGB data or other custom profile.
-using profile info translate RGB data in photo to XYZ coordinates (usually PCS coords)
-read using OS api “current display profile” for Screen N.
-reencode (relative whitepoint: rel col or perceptual) XYZ coordinates of each pixel in image previously obtained to RGB data in display colorspace.I have used google translator in your link and it seems the he thinks that you are talking about camera profile, the way you develop a RGB image from sensor data.
You can try to clarify this about monitor since monitors can (and do) have arbitrary native gamut colorspaces. For example is prrety common that 9x% multimedia displays have near sRGB blue primary, near P3 red primary and a green primary in the middle ground/intersection between B-G line in P3 with G-R line in AdobeRGB.
Also typical monitor for phioto editing has near sRGB blue primary, near P3 red primary and near AdobeRGB green primary.
As you can see there is no “standard colorspace” for these monitors, at best you can trust driver/EDID generated ICC with this info, publish it to OS as “default display profile” in OS settings and let each app ask OS for display profile, feed this data to its own CMM (like LitteCMS) and feed transformed RGB data to image canvas as raw RGB data to monitor (rendering that RGB data to Win GDI).Even if my display has HW calibration that can simulate smaller than native colorspaces like sRGB/AdobeRGB… there is no need to limit it since image’s colorspace is arbitrary too. I can open in Photoshop a sRGB TIFF, an AdobeRGB TIFF, a ProphotoRGB TIFF, a TIFF with a custom interchange profile…
=> hence image editors must use a CMM.I have used google translator in your link and it seems the he thinks that you are talking about camera profile, the way you develop a RGB image from sensor data.
He <knows> it (a monitor profile), but don’t <understand> it.
In his world, all monitors are standard, and everything around is marketing by Adobe.
I’m tired of arguing with him.
Too bad. He has such a great program. It develops photos better than rawtherapee/dt. The 3d
lufs tools, which has no analogue in any of the programs. And breaking through his brain is easier than breaking through a meter-thick concrete wall with a projectile. An elderly man working at the institute. He knows a lot. Therefore, if he encounters something new, he rejects it.
