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37

Why? Because PNG is a lossless raster image format developed for the web, and ultimately for display screens which are RGB. However the format was never intended or designed to be a print format, and therefore doesn't need to support CMYK colour, and so it's entirely the wrong format to use for CMYK printing - i.e printing where separations are required ...


28

here is the technical answer Saying that the color is #dd0017 is meaningless, unless it is paired with information about what color space you are using! Therefore also conversion from #dd0017 to CMYK is meaningless. With this off our agenda we can start to look what same would mean in your scenario. When you talk about pure color like #dd0017 you are ...


27

Illustrator Make certain you open any new document in CMYK color mode. Yes open in CMYK, don't switch to CMYK if you opened an RGB document by mistake. Many things in Illustrator are dependent upon the document color mode. The Swatches, symbols, graphic styles, brushes, are all built to match the Document Color Mode. Switching color modes mid-stream does ...


23

You have "Only Web Colors" selected. Turn that off as its essentially irrelevant on modern computers. It's trying to figure out how to best represent 50% K in a vastly reduced RGB palette known as Web Safe Colors.


19

It comes from: 1. The imperfection of inks An ink is made from available materials, which need to be affordable, safe, reliable, etc. and they need to give reasonable results. With the current technology, the inks are a good compromise on those points, but they are not perfect. When we combine 100% of Cyan, magenta, and yellow, they do not manage to ...


18

Talk to the production house and ask them what rich black they prefer. There is no single rich black every print provider uses. Each print provider has their own formula for a rich black. And, in many cases, the print provider may want simply 100% K and they will adjust the black to match their own environment. Therefore, the best option is to ask the print ...


17

The range of colors that can be reproduced in any CMYK-only color (known in the trade as "Process Color") printing method is considerably smaller than the sRGB range of colors reproducible on a standard monitor. Here is an excellent video that demonstrates this visually using 3D color models. It happens that one of the ranges of RGB color that can't be ...


17

A monitor can't show true CMYK. CMYK is reflective light, or subtractive color. A computer display is projected light, or additive color. They take up different (albeit overlapping) color spaces. Your software does its best to emulate the CMYK colors converting them to RGB but it simply can't replicate them exactly. "When ever I'm choosing color while ...


17

RGB is an additive spectrum... you ADD colors to get white. Dkuntz is correct stating that RGB is light-based. It is. It uses the visible light spectrum to display colors. CMYK is a subtractive spectrum... you REMOVE color to get white. DKuntz's use of the term "color-based theory" is really nonsensical. Since RGB is also a color spectrum. A more ...


16

C = Cyan M = Magenta Y = Yellow K = Black B was not used as an abbreviation because it could be confused with "blue" from RGB, or "blue/yellow" from L*A*B In addition to being an excessive amount of ink..... 100C/100M/100Y will yield a dark brown, not black.


15

Broadly speaking there are two schools of thought on file-format design. One is that you should have lots of options to give lots of different users what they want. The problem with this approach is that compatibility becomes a problem. Just because a program advertises support for tiff files doesn't mean it can open your particular tiff file. The other is ...


14

On spot blacks Many of the other posters have discussed parameters for rich blacks in process colour. It's also worth noting that you can mix spot blacks (and other spot colours in fact) with process colour in documents. For example, it is common practice to print text in a spot black ink on a process colour document. Process black ink is intentionally ...


14

Great question! To take the last part first, your skin hue would be the same no matter the brightness of incident light, provided the color of the light didn't change. That's why "Select skin tones" works in Photoshop CS6 and later. In broadcast video work, there's a commonly-used tool called a vectorscope that will prove to you, if you ever test it out, ...


14

NOTE: This got way longer than I expected, and I purposely glossed over a LOT of detail. If you'd like me to elaborate, just ask. PMS Colors - Absolutely brilliant when used as designed for pre-mixed spot color offset printing. You can be assured the color you saw in your Pantone book is very closely represented in your final printed piece. The problem is, ...


13

Short answer: you can't. Technical answer: RGB is additive. The more color (made of light) you add, the closer you get to white. CMYK is subtractive. The more color (made of ink, which is reflective, which subtracts light) you add, the closer you get to black (or actually a muddy brown). CMYK has a smaller range, or gamut, of colors it can reproduce than ...


13

There is no way to print RGB colors in CYMK simply because you can't 'print' RGB, as it's a projected light color space, not a reflective light (ie, ink) color space. Many colors overlap in RGB and CMYK spaces, but not all, as you've found out. You can use spot colors to print more colors that CMYK can provide--which can get you closer to what you might ...


13

... if I try to assign a text the color #00FFFF it automatically sets it to #6FCCDC instead of converting it to CMYK. It is converting it to CMYK... CMYK and RGB have a different gamut, so converting from one to the other will result in color changes. The hexadecimal colors you have there are an RGB notation, so if that color doesn't exist in the CMYK ...


13

I can't really claim to know much of anything about mixing house paint.... It's my understanding though that the mixing system is more akin to a Pantone mix than a CMYK mix. On screen, it would be just a black. It would equate to 0R0G0B so.. black. ---> RGB -- > On press.. it'll get rejected by most prepress departments or at least get changed. The ...


13

As Billy Kerr wrote, Hex is not a colour space, but a numerical system such as the decimal system, but with base 16. The differences you notice are probably caused by different RGB colour spaces (such as sRGB vs. AdobeRGB), i. e. the RGB numbers from your graphic designer describe another colour than the mentioned online tool.


12

Not to detract from Marc's excellent and comprehensive answer, there are some points that are worth a bit more explanation. It's a big subject. This gets geeky before it gets better, so bear with me and follow closely. :) CMYK and RGB are "color models," not color profiles. A color model is a way to represent colors using numbers. There are other models, ...


12

There is no mention of CMYK in the GIF specification, and it only supports color triplets. Take a peek at the syntax for color tables given by the spec: 7 6 5 4 3 2 1 0 Field Name Type +===============+ 0 | | Red 0 Byte +- -+ 1 | | ...


12

The short answer is no, a GIF can't support a CMYK profile. A CMYK profile is a series off curves that map the percentage value of each separation to a target. GIF images are saved as INDEXED COLOUR, which then references an RGB value for each colour. While CMYK values could be derived from the RGB values (the RGB gamut is wider than the CMYK gamut so some ...


11

A few precisions on the use of pure black and rich black... Some things are misleading and have not been explained in a very technical way; once you understand how things really work, it's easier to make the right choice. First, black is not gray, it's black. The reason why it may appear "charcoal" on screen it's simply because it hasn't been enriched with ...


11

It's actually far simpler than it may first appear. The bottom line is that it's best to convert to the most native format as early as possible. Full colour printing typically uses four inks to create a photorealistic image. In theory, cyan, magenta and yellow should be enough to print a high quality image, but adding black aids the printing process, giving ...


11

Welcome to what is probably the Number 1 'gotcha' for people new to print design :-) and yes, people who encounter it for the first time not pre-warned almost always run into just before a deadline... RGB black is simple. It's just no light coming from the screen. CMYK black isn't simple. There's black ink (the 'K' in CMYK), but even with 100% black ink, ...


11

I would contend that this is difficult to answer definitively. If you're talking a four-color process, a straight 100% 'Y' would probably be your best bet. However, highlighters tend to have a neon glow about them, which can't be achieved in CMYK. You'd need a special process color for that. Get your hands on the highlighter you want to emulate, draw on ...


11

To add on to Brendan's answer, the "Neon" quality of "Neon Yellow" can be achieved in CMYK, but that's not all a highlighter is. A physical highlighter doesn't contain the pure yellow we expect from printers and monitors, but a slightly more watered-down version, so step one would be to use, say, 75%-80% yellow to start with. Next, to achieve that ...


11

Options: Convert your art to CMYK and print it as-is. Convert your art to CMYK, and manually adjust the values to increase their vibrancy. (RGB to CMYK conversion can make things look muddy, especially those bright blues). If you're in photoshop, you can try a few different Adjustment Layers to get the colors closer to where you want it. Color Balance and ...


11

I will only complement the other answers. RGB to HEX will give you the same exact color. RGBA to HEX, will not because we do not even know what is beneath the color. If you put another color the overall color will change... that is the whole point of transparency. So you have three options. Convert the RGB values to HEX (without the alpha value) and add ...


10

Go to View > Gamut Warning (or hit Command-Shift-Y) to turn on the Gamut Warning feature. This will 'grey out' colours that are not available in the current gamut. Command-Shift-Y will also toggle this on/off while in the colour picker. You can change the colour and opacity of the greying out effect in Photoshop > Preferences > Transparency & ...


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