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12

xvYCC is a particular clever way of encoding color data: it abuses the YCC representation by using previously-forbidden combinations of values to represent colors outside the gamut of the RGB space used in the YCC scheme. That is, some YCC tuples decode to colors with negative R G or B values. Previously these were simply illegal; in xvYCC these are ...


11

The tool displaycal-profile-info, part of the DisplayCAL package, can do this. This works (and works basically the same way) for Windows, Mac, and Linux. See for example for my (calibrated) ThinkPad screen: ... which has a 60% coverage of sRGB and 43% coverage of Adobe RGB.


10

I am a former broadcast engineer, and I currently work in feature films and television as an editor and VFX supervisor. Many statements on here are incorrect. Gamma in the signal path is a desired benefit, and a design choice by early video engineers to reduce perceived noise in transmission. All vacuum tubes, CRTs included, exhibit various non-linearities ...


10

from Charles Poynton "The rehabilitation of gamma": Misconception: The nonlinearity of a CRT monitor is a defect that needs to be corrected. Fact: The nonlinearity of a CRT is very nearly the inverse of the lightness sensitivity of human vision. The nonlinearity causes a CRT’s response to be roughly perceptually uniform. Far from being a defect, ...


7

Consider this example from Cambridge in Colour: By applying gamma encoding, we are able to represent the original image more accurately, with the same bit depth (5, in this example). This is achieved by using the 32 levels in a way that more closely corresponds to the human eye. In other words, it's a form of compression. JPEGs, for example, can actually ...


7

This is a very incomplete answer, but important in regards to terminology and understanding everything: RGB and CMYK are color models. They don't define what your monitor or printer can do, only how color is created. A great question to review: What is the difference or relation between a Color Model and a Color Space? He also told me CMYK is a 100% ...


5

The camera sensor does not have a color space that allows going back and forth to XYZ since it does not have the same sensitivity curves as the human eye (Luther - Ives condition). The best that can be done is come up with a transform matrix that minimizes the sum of the errors in LAB for the set of standard colors (Gretab -Macbeth). I believe this process ...


5

CMYK CMYK is a subtractive colour model rather than an additive as in the case of sRGB. The subtractive colour models are used in printing since they allow dyes, ink or paint pigments to absorb certain wavelengths from an otherwise white surface. The dyes, ink and paint pigments can be a very limited discrete set that are mixed to get a wide range of ...


5

In my opinion the designer is wrong. CMYK is NOT a subset of sRGB. It is a diferent color model. Let me explain. sRGB is a color profile for rgb colors. But actually it is close to a "color space" (yes, this afirmation will be controversial). On top of that you "profile" your monitor and computer conected together. But there are tons of diferent ...


5

Part of this question basically seems to be asking if the answers to the other question are actually right. For that part, don't worry — they are. (And no information is lost in this way — the leader of your course is wrong. *) The other parts of the question basically ask if (and why) this information is stored at all, if it doesn't affect the raw data. ...


5

That Adobe seems to butcher the colors of all my raws drives me nuts You are wrong here. What you see on the back of your camera is not the raw file, but the JPEG preview, which includes whatever setting you dial in your camera. That includes contrast and boost of saturation. LR cannot reproduce the same look from the raw file, because the process is ...


5

Let me first say that everything that's happening is exactly how it should be. Even the fact that Photoshop gives you a warning, which is a matter of its Color Settings (see below). And your concerns are absolutely valid. In a TL;DR fashion, I'll say this: only use a non-sRGB profile if: You have a colour-calibrated monitor (and, in fact, the whole ...


4

The covered range of colors (called gamut) is different between color spaces because these ranges are then discretized, "digitized", represented on a fixed amount of bits, and then reproduced on a monitor, in print, etc. One wants to store as much color information as possible in a certain amount of bytes. Now, if you have an equipment which can only emit ...


4

Is it possible to calibrate correctly and identically (or nearly) 2 monitors? Only if they're identical display types. There are many different types of LCD display, and several non-LCD display types besides. Two different display types may simply be incapable of producing the same color gamut, brightness levels, evenness of illumination, contrast, etc. ...


4

In Adobe Photoshop, there are two menu options: "Assign Profile" and "Convert to Profile". If you have an image in the ProPhoto RGB color space, and you "assign profile" sRGB, this just changes the metadata in the file as to which colour space the RGB values refer to. It will give you the effect you want. If you were to select "Convert to Profile", this ...


4

If you have a spyder 5 pro it will give you a chart and percentages of coverage for srgb, ntsc, and adobe rbg Here is my srgb result


4

If the original ICC profile is sRGB or equivalent, there is usually no harm from removing it. sRGB is sometimes added to images that were not originally color managed. (The profile shouldn't be included with the image in the first place.) sRGB corresponds to the full color range of unmanaged systems. (Whether the image is tagged or not, it will appear the ...


4

Adobe RGB image in a monitor that only displays sRGB? I'm not sure if here lies a misconception. A monitor does not only displays sRGB or Adobe 1998, they display a percentage of them. If a monitor displays 100% sRGB color space it will display a percentage of the other (70%-80% ish. I'm not sure at the moment). I am sure you have seen the typical graph ...


4

This is a valid concern. My understanding of your question is that it's a monitoring problem rather than editing problem. That is, when you are editing an sRGB photo, you specify that your current worskpace is sRGB, instead of converting it to AdobeRGB first. In this case, all your editing is happening with full 8 bits (or 16/32 if you select so in the ...


3

CMYK is based off of offset printing capabilities where you are using only specific shades of Cyan, Magenta, Yellow and Black ink being laid down from separate printing plates to print full color. It isn't mechanically capable of reproducing very saturated colors. But ... most photo inkjets don't expect you to send generic CMYK files to them. They have ...


3

This is just a visualisation. The colours in the diagram do not represent the real colours of the noted wavelengths (what you see is dependent on the capabilities and calibration of your monitor anyway), but are chosen to give you an idea where the different colours rougly lie.


3

There's a lot of confusing articles on gamma correction with many vague references to gamma and human vision. The reason for gamma is historical and a result of the response curve of the old CRT-type monitors (nothing to do with human vision). With modern day flat screens there is no logical reason for gamma encoding and subsequent correction, but it has ...


3

Yellow is not a native color of the monitor. The screen is composed of red, green and blue sub-pixels. If red, green and blue all look fine, then something else is going on with the yellow. There is a good possibility that this is a physical limitation of the screen's color gamut, since you said that full red and full green look the same, but full red and ...


3

That is precisely what was used in Kodak Photo CD (the colorspace is called PhotoYCC), moreover it is a predecessor of xvYCC_601. The problem why it was not done is because it is ONLY limited range (as Cb and Cr components are extended for extended gamut, while Y' stays the same), while full range is preferred for photo imagery; the other problem is there is ...


3

Honestly, two different monitors are always very very hard to get the same. If you really want them both to look the same, you should get two of the same monitor. This is especially difficult in your situation, where one is a touch screen (lots of wires an other bits to alter the color). Plus they are both TN panels, so the color will shift depending on the ...


3

One thing I don't fully understand is why, when I take a photo with a Nikon and import it in Lightroom, the colors immediately appear desaturated and visibly different than what it looked like in the camera. This is just a different interpretation of the raw data. Lightroom can't read the preset information from Nikon files, it seems and applies some sort ...


3

Before you worry about whether you should export as P3, does your camera even export in P3? Most cameras today still only export in either sRGB or Adobe RGB. However, if you're using an iPhone for capture (or any other camera that supports P3), then your images support P3. When a P3 image is rendered on an sRGB screen, software that works correctly will ...


3

You list different things. The 2001 reference is an ICC Specification that defines how V2 profiles are structured. The specification applies to profiles such as sRGB as well as others such as ProPhoto RGB and even printer profiles. The 1966-2-1 is not a year. It's a profile description document number and does specify sRGB which was created jointly by HP ...


3

If I stick to Case A: Could I be sure that everyone (with calibrated monitor) will see my photos as me in smart "viewers": ACDSee Pro, LightRoom? Not if the other calibrated monitors are only 96%, or 90%, or any other portion of sRGB other than the exact same 99% of sRGB that your monitor renders. The 1% your monitor can't display may even be different from ...


3

It's hard to say what the 'Standard' setting is supposed to do on each particular monitor. From my experience with similar monitors, where there are 'actually standard' presets like sRGB or AdobeRGB and then some others, the Default or Standard preset can be one of two things: The 'native' display, without any built-in corrections. The 'best looking' ...


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