#1 is definitely a problem. However, does RGB/CMYK/Hex not solve this?
Accurate colour reproduction, that enables you to get half a dozen things made in different parts of the world then put them next to one another and have them look the same, is a really tricky process control problem.
(One of the historical reasons Apple were popular with designers is that they do care about colour accuracy and things made on a Mac will generally look the same on other Macs unless you've fiddled with the calibration yourself. PC OEMs and Microsoft don't care about this.)
As for CMYK, there is a difference between spot and process colour. CMYK is process colour, made of lots of small spots of cyan, magenta, yellow, and black ink. There are different ways you can do this and you will get different effects. For example you could have grids of dots, but you could have the grids at different angles.
Spot colour (pantone) is just ink that is that colour. You get exactly the same every time, no matter the printer.
In that scenario, what is the deliverable to the manufacturer or the printer as it pertains to a specific color? What specifications are they using to match against a defined pantone? Is it too a matter of matching against a swatch? That seems arduous at best!
I understand that the answer is a "no" and that I'm wrong. I just don't know why I'm wrong.
But if YOU have a pantone swatch and I have the same pantone swatch. We now have a reference that is the SAME color. I can tell you to keep adjusting your local parameters until the thing you're coloring (paper, fabric, plastic, rubber, metal) matches the swatch.
It's the same with printing, except that calibration is more effort and expense. Enter Pantone. Pantone inks are pre-mixed so the color is always consistent. What printers do is they print most of the image using the normal four-color process (CYMK) on a "best-effort" basis and then do a separate pass on critical areas using specific Pantone inks that are guaranteed to yield a specific color. The extra process is expensive so spot colors are typically limited to brand-specific colors (e.g. Coca-Cola Red) and other things where precise color reproduction is important.
No, not at all. Pantone seems arduous because you're unaware of all the simplifying assumptions that you're otherwise making.
Your perception of a color for a single illumination stimulus is indeed a simple three-dimensional quantity (as your eyes have three color channels). But the stimulus itself is defined by an intensity at every wavelength.
For an extreme example, something that fluoresces takes in say UV light and outputs lower wavelengths. I think the Pantone model simplifies away things like fluorescence as well [0], but I've thrown out the example to show how many dimensions we're actually dealing with.
For a purely diffuse example, first take a look at https://en.wikipedia.org/wiki/File:Cones_SMJ2_E.svg . To my approximate reading, 530nm and 575nm have equivalent responses for your "green" color receptors. If we have one material that does not bounce 530nm and one that does not bounce 575nm, they can look the same if illuminated with equal amounts of each [1] but then look different if illuminated with a "same colored" source that is lacking 530nm. This is why people have problems with fluorescent and LED lights - colors look weird because their emissions are "peaky" and not the smooth "black body" curve we're used to.
[0] Although maybe not, with the prevalence of whiter-than-white papers, laundry detergents, etc.
[1] With each material having the appropriate amount of red/blue bounce to equalize those channels as well.
A real color is a mixture of reflected wavelengths and more, for example a fluorescent marker is that, fluorescent, you give it UV light and you get green.
A real color in real life behaves different depending on the light that illuminates it, and the angle of incidence.
RGB and CMYK is display-specific primary inks dependent. There are spaces for device independence colors. They work well for cinema and places were illumination is controlled and restricted.
Pantone let you control a color over a broad range of circumstances on the real world, like color of a shirt at the sunset.
It looks like the stupidest of things, but a client buys you a suit that looks great at the shop but bad on his house or office illumination and he will ask for a refund.
The same thing with a big poster on a building on London weather(totally different than on Madrid or Rome).
Here is a good link that explains things a bit: http://www.printernational.org/rgb-versus-cmyk.php
I'm in the t-shirt printing business and this is a major issue with artwork that we print. Explaining to people that we can't print their RGB image with the exact colors in it is a major pain.
When you're taking bottles of ink off the shelf and mixing them, you just are not going to be able to represent all the colors in the RGB space.
This is not really true. They're different things. One is spot colour, one is process colour.
Process colour - lots of very small dots/splodges/lines made of just a few ink colours (typically Cyan, Magenta, Yellow, and Black).
Spot colour - ink that is that colour.
There is no room for intepretation with spot colour. It is the colour it is.
Even CMYK can be a "different" colour. Different printers (both people and the machines) can print CMYK differently. It is possible to print CMYK without the K, for example. It's very difficult to see the difference and it saves a chunk of money on ink. The output is a different colour though. ;)
Pantone colors are such a system, with very exact control over what you get.
Light entering the eye can be thought of as having a range of wavelengths over the visible spectrum. A red source of light might be pure red, with a single wavelength right at the peak sensitivity for the red cone receptor of the human eye, but it might also be, and in most cases will be, a mixture of wavelengths some stronger some weaker falling across the visible spectrum that happen to stimulate the red cones more than the blue or green cones.
Visible light, made up of a collection of wavelengths, can be described as an intensity curve for each wavelength, that is, a real valued intensity function of wavelength. However, the brain is incapable of knowing the shape of this curve, it only knows how much each of the three types of cones are being stimulated. Two very different "colors" having wildly different distribution of wavelengths might be perceived as exactly the same by the human eye. Furthermore, the brain does a bunch of processing that changes the perceived color in strange ways, see for example, the Land effect [2], named after E. H. Land (creator of Polaroid cameras) because of his work on understanding it.
Finally, why isn't RGB enough? Each Pantone color, say Pantone Coated Warm Red C, does have an exact RGB (or CMYK) value, in this case #F9423A. The problem is that pigments in inks and pixels in cameras and the pixels in screens all generate or are sensitive to specific sets of wavelengths that won't exactly correspond with each other or with the sensitivity of human eyes. This is why we need color profiles and color spaces and all of the concomitant complications (especially so since the functions involved are not simple linear transforms).
A sophisticated enough sensing device could be constructed to exactly mimic the sensitivity of the human eye. It could report the apparent color of any object, say a fabric swatch, in three dimensions, say R, G, and B. Such a device could be used to compare a color in China with on in New York. It's just more convenient to use the ubiquitous color swatch strips produced by Pantone and match the colors by eye, and by now, one can simply load your offset printing press with ink matching Pantone Coated Warm Red C straight from the ink manufacturer.
[1] https://en.wikipedia.org/wiki/Spectral_sensitivity
[2] http://www.millenuvole.org/f/Fotografia/Per-quali-ragioni-ve...
In other words, the eye as a light sensor to match a color in the physical world is the most efficient solution we have, no?