6 ms·

#1 is definitely a problem. However, does RGB/CMYK/Hex not solve this?

by cheath 10y ago

Vraxx 10y ago
Hmmm, based on his other problem, my speculation would be that not areas have the exact same printer tones with the same hex/rgb values in software? It does seem a bit strange if that were the case though.
latchkey 10y ago
CMYK is a subset of Pantone. CMYK is essentially the color space for printed things. RGB doesn't convert 1:1 to CMYK and even lies outside of Pantone in some spots. Here is a good link that explains things a bit: http://www.printernational.org/rgb-versus-cmyk.php 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.
- shocks 10y ago
  > CMYK is a subset of Pantone. 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. ;)
  - latchkey 10y ago
    True true! Thanks for the clarification. I was trying to just simplify the concept. It is all so overly complicated...
    - shocks 10y ago
      Yes, it is super complicated. I do print for a living too, I know exactly how hard it is to explain to a customer that the colour they want cannot be printed! Haha. :D
theatrus2 10y ago
In what color space? Is this in the target color space? What printer do they have? Are you doing offset printing? 4-color? On what paper? etc. Pantone colors are such a system, with very exact control over what you get.
shocks 10y ago
Well you definitely shouldn't be using RGB/Hex for print. Lots of these colours cannot actually be printed, and there are different algorithms for converting them to printable formats (that give different results). 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.
- ja30278 10y ago
  NB: you've mixed up spot and process colors ( spot = pantone, process = CMYK dots ), but otherwise correct.
  - shocks 10y ago
    Blah, you are right. I will correct my comment.
- medmunds 10y ago
  (I believe you've swapped the labels: process color mixes dots of CMYK inks to approximate other colors; spot color uses an ink pigmented to the precise color you want. https://en.m.wikipedia.org/wiki/CMYK_color_model https://en.m.wikipedia.org/wiki/CMYK_color_model )
  - shocks 10y ago
    You are correct. How embarrassing! I have edited my comment. Thanks. :)
- cheath 10y ago
  so, humor me this. I understand that a Pantone color is definite. A designer with the swatches should be able to expect that matched outcome in, for example, a manufactured textile. 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!
pjc50 10y ago
Absolutely not. RGB values tell you surprisingly little about what something will look like on a screen, as screens have different colour profiles. Similarly print processes aren't linear either, especially across different materials. Then you have to consider things which aren't printed in any sense like injection moulded plastic. And as others have pointed out there are different "gamuts", so that RGB and CMYK don't even represent the same set of colours. That's before you consider colours like International Klein Blue: http://www.tate.org.uk/art/artworks/klein-ikb-79-t01513/text-summary http://www.tate.org.uk/art/artworks/klein-ikb-79-t01513/text... (has to be seen in person as it's not a web-reproducible colour) 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.)
wolfhumble 10y ago
The type of paper you are using (matte, un/coated) will also have an effect on how the color will be presented, so it is often useful to use a physical color guide were colors are printed on different stocks. See: http://www.pantone-colours.com http://www.pantone-colours.com
cptskippy 10y ago
RGB is a light color system and CMYK is a pigment color system, conversion between the to is not 1:1. However on properly calibrated monitors and printers, Pantone Cornflower blue is the same.
pipio21 10y ago
Not really. 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).
todd8 10y ago
A big issue is that the human eye doesn't have R, G, and B sensors with well defined boundaries. Light frequencies that stimulate the cones receptors in the eyes cover a range of wavelengths from about 400nm to 700nm, see the first figure at Wikipedia's page on spectral sensitivity [1]. The three types of cones have largely overlapping sensitivity to light. 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 https://en.wikipedia.org/wiki/Spectral_sensitivity [2] http://www.millenuvole.org/f/Fotografia/Per-quali-ragioni-vediamo-i-colori/edwin_land_the_retinex_theory_of_color_vision.pdf http://www.millenuvole.org/f/Fotografia/Per-quali-ragioni-ve...

#1 is definitely a problem. However, does RGB/CMYK/Hex not solve this?

by cheath 10y ago

#1 is definitely a problem. However, does RGB/CMYK/Hex not solve this?

Vraxx 10y ago

Hmmm, based on his other problem, my speculation would be that not areas have the exact same printer tones with the same hex/rgb values in software? It does seem a bit strange if that were the case though.

latchkey 10y ago

CMYK is a subset of Pantone. CMYK is essentially the color space for printed things. RGB doesn't convert 1:1 to CMYK and even lies outside of Pantone in some spots. Here is a good link that explains things a bit: http://www.printernational.org/rgb-versus-cmyk.php 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.

shocks 10y ago
> CMYK is a subset of Pantone. 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. ;)
- latchkey 10y ago
  True true! Thanks for the clarification. I was trying to just simplify the concept. It is all so overly complicated...
  - shocks 10y ago
    Yes, it is super complicated. I do print for a living too, I know exactly how hard it is to explain to a customer that the colour they want cannot be printed! Haha. :D

theatrus2 10y ago

In what color space? Is this in the target color space? What printer do they have? Are you doing offset printing? 4-color? On what paper? etc. Pantone colors are such a system, with very exact control over what you get.

shocks 10y ago

Well you definitely shouldn't be using RGB/Hex for print. Lots of these colours cannot actually be printed, and there are different algorithms for converting them to printable formats (that give different results). 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.

ja30278 10y ago
NB: you've mixed up spot and process colors ( spot = pantone, process = CMYK dots ), but otherwise correct.
- shocks 10y ago
  Blah, you are right. I will correct my comment.
medmunds 10y ago
(I believe you've swapped the labels: process color mixes dots of CMYK inks to approximate other colors; spot color uses an ink pigmented to the precise color you want. https://en.m.wikipedia.org/wiki/CMYK_color_model https://en.m.wikipedia.org/wiki/CMYK_color_model )
- shocks 10y ago
  You are correct. How embarrassing! I have edited my comment. Thanks. :)
cheath 10y ago
so, humor me this. I understand that a Pantone color is definite. A designer with the swatches should be able to expect that matched outcome in, for example, a manufactured textile. 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!

pjc50 10y ago

Absolutely not. RGB values tell you surprisingly little about what something will look like on a screen, as screens have different colour profiles. Similarly print processes aren't linear either, especially across different materials. Then you have to consider things which aren't printed in any sense like injection moulded plastic. And as others have pointed out there are different "gamuts", so that RGB and CMYK don't even represent the same set of colours. That's before you consider colours like International Klein Blue: http://www.tate.org.uk/art/artworks/klein-ikb-79-t01513/text-summary http://www.tate.org.uk/art/artworks/klein-ikb-79-t01513/text... (has to be seen in person as it's not a web-reproducible colour) 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.)

wolfhumble 10y ago

The type of paper you are using (matte, un/coated) will also have an effect on how the color will be presented, so it is often useful to use a physical color guide were colors are printed on different stocks. See: http://www.pantone-colours.com http://www.pantone-colours.com

cptskippy 10y ago

RGB is a light color system and CMYK is a pigment color system, conversion between the to is not 1:1. However on properly calibrated monitors and printers, Pantone Cornflower blue is the same.

pipio21 10y ago

Not really. 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).

todd8 10y ago

A big issue is that the human eye doesn't have R, G, and B sensors with well defined boundaries. Light frequencies that stimulate the cones receptors in the eyes cover a range of wavelengths from about 400nm to 700nm, see the first figure at Wikipedia's page on spectral sensitivity [1]. The three types of cones have largely overlapping sensitivity to light. 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 https://en.wikipedia.org/wiki/Spectral_sensitivity [2] http://www.millenuvole.org/f/Fotografia/Per-quali-ragioni-vediamo-i-colori/edwin_land_the_retinex_theory_of_color_vision.pdf http://www.millenuvole.org/f/Fotografia/Per-quali-ragioni-ve...