Hot answers tagged cmyk
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It's one of the Big Things You Must Know about printing that Black (0,0,0,100) is not black; it is a dark gray. I mean really important, as in "If you don't know this, you're going to get in expensive trouble sooner or later." The reason it's gray, rather than black, is that the ink is partially absorbed by the paper and is in any case a very thin coating, ...
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I know this sounds a stupid question, black is black right?
Not really. It all depends on colour model used, ambient light, substrate, and perception. Black is, by definition, no light hitting our eyes. This is very difficult to accomplish. :)
CMYK is a Subtractive Colour Model. It is used in printing because the mixing of the different pigments of ink ...
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During the RGB ⇒ CMYK conversion your RGB(0,0,0) values are probably converted to Rich black = CMYK(63,52,51,100) or such; and looks washed out when compared to Plain black = CMYK(0,0,0,100)
Solution is to fine tune the RGB ⇒ CMYK conversion.*
See also: Rich black versus plain black and gd.se question: What is the difference between CMYK and RGB?
*) To ...
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In Offset printing the fifth colour is an additional spot colour, which could be anything (of course depending on the printer/printer services). I've yet to hear what is the single most common "fifth colour".
Why? For example in (now discontinued) hexachrome (CMYKOG, yes 6 colours) printing process orange and green were added to achieve wider colour gamut ...
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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 ...
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LAB (aka CIELAB), space is quite useful. It's good for exaggerating color differences, relating colors to color opponent theory. I do a lot of image enhancement and digital art creation from photographs in CIELAB or spaces that resemble it. Its main advantages are separation of color from brightness and roughly evenly spread out color changes - two ...
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CMYK and RGB are the two colour spaces, methods of creating colour.
CMYK is subtractive, like paint/pigment. you start with nothing (white paper) and as you add more colours it eventually turns black. CMYK represents the standard coloured inks that printers use to create colours: cyan, magenta, yellow and black.
RGB is additive, the way light creates ...
7
Koiyu's answer would fit if you are talking about sending to a printing press, but I suspect you're outputting to an inkjet printer. In that case, the answer is almost the opposite, because there is no CMYK conversion involved.
I'm going to assume that your screen grab is genuinely black. You can check that in Photoshop, as JAG2007 describes, but a screen ...
7
A bit of overlap with what I just answered here, and you can grab urls from there, but yep, a Gimp and or Inkscape --> Scribus workflow might be ok. ( Edit: or maybe just sk1 )
Actually done it? Yep. I indeed work with mostly free and open source tools. No complaints :)
In my experience, you often have to use heavily your brain and create your tricks to ...
7
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 ...
7
The easiest way would be to create a selection around the bar code (I assume it's got the white background), then using the Channels Panel -
Hightlight the black channel and use Levels to boost the tone to 100%.
Then Highlight the C channel and fill the selection with white.
Then fill the selection on the M and Y channels with white as well.
Double check ...
6
No, you aren't missing something. There is no point at all in converting images to CMYK, and several good reasons NOT to. Converting images to flattened CMYK tiff is an old QuarkXpress workflow that is a complete waste of time today, especially with InDesign.
What is a good idea is to size images in Photoshop before final output, to reduce file size and for ...
6
HSV (also called HSB) is based on the RGB system - it's actually just a transformation of the RGB color space (so it's still additive, and is intended for computer displays). The three components of this color system are:
H: Hue. This is the angle on the color wheel. Starting with red at 0 degrees.
S: Saturation. This is the ammout of 'color' in the color. ...
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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 ...
6
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 ...
6
The easiest way to do this is to open your image in grayscale mode in Photoshop (or convert to grayscale mode if it opens it in RGB/CMYK format).
From there, choose Image->Mode->Duotone.
Make sure the type is set to Monotone. Ink 1 will be set to black. Click on the black box, to access a color picker. Choose the color you want (use the color libraries ...
6
The premise of the question is flawed for a few reasons.
A print proof is meant to mimic the final product. The idea is that you view the proof with the expectation that the final product will look exactly like that.
That concept doesn't exist on the web. For a number of reasons:
There is no defined canvas size. Unlike a piece a paper, a web browser can ...
5
If you're printing CMYK, add some CMY to your K and you get a rich black. It's darker and comes across are a more 'true' black when printed. It also helps with trapping and as you're less likely to see white gaps if your registration is slightly offset. As for how much of each to add, that can depend on a number of things, but Lauren is pretty much correct: ...
5
This is one of those bizarre problems, the answer to which is important, but fairly non-obvious.
Your best CMYK<>Pantone match is obtained not from the application, but using the Pantone Color Bridge book (not the software version in your applications). Truly. But I know we all like to do it in software, so here are the gotchas for AI and ID:
In ...
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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 ...
5
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 ...
5
I suspect this came about by working in RGB to start with, then converting to CMYK. This would turn your RGB(0,0,0) text into a colour composed of all four CMYK channels, rather than pure 100% K.
As Marc and Scott say, body text should be 100% K.
(If you did need a stronger black, you's be better of going for a double hit of the black plate rather than ...
4
Photoshop handles the RGB ⇒ CMYK conversion according to the colour profiles you've set.
What Photoshop suggests for you here is a variation of rich black. As the name implies, rich black looks richer when printed since it produces more layers of ink instead of just one layer of black (K) ink.
You can tune the conversion in Edit → Convert to profile → ...
4
In addition to koiyu's excellent answer, a fifth color might be a "double hit" of a color which is being printed in CMYK, to make it pop. For example, Pantone 186 red might print a little muddy in process, so a fifth plate is added of the same Pantone 186 in spot, to make the red brighter.
I've also heard of the fifth "color" used to refer to a varnish ...
4
It is a misnomer, or at least confusing, to say both: "RGB is based on light and it's additive because you start with no light" and "CMYK is based on ink and it's subtractive because you start with no ink".
It is easy to understand how RGB works, as the usual displays create colors by adding the additive primaries, red, green and blue, together in ...
4
Your original question has been adequately answered, but since you're a photographer, it's important to recognize that there are different RGB color spaces.
The three you'll most often come across in photography are "ProPhoto RGB", "Adobe RGB" and "sRGB". They all measure color using the RGB model (amounts of Red, Green and Blue light), but differ in their ...
4
As Lauren says, there are colors that you can achieve with Pantone (or any of several other, similar brands) spot colors that are impossible in CMYK. Bright oranges and rich blues are beyond the capability of regular CMYK, for example. Color accuracy (or, perhaps, color certainty) is another major reason to employ spot inks.
If you look on the Pantone ...
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Spot colors are premixed ink. It will often print more precisely than CMYK, since the CMYK color space has some limitations in the range of colors it can produce.
Sometimes CMYK colors are muddier or darker than spot, but it depends on the color. Certain colors like metallics and some pastels can't be reproduced in CMYK and must be printed spot.
If it's a ...
4
A few things...
You should stick with one printer if color accuracy is important. There are going to be variations on one press enough as it is, and adding a second one will just make things more exciting.
The better printers I have come across will offer for free a color profile to calibrate your in-house equipment with so that you can better gauge how ...
4
A couple of points adding to Lauren's and e100's excellent answers:
1) A desktop printer is an RGB device, not CMYK. Although the inks most such printers use are the standard four, sometimes with additional inks (my Canon proofing printer adds a "photo cyan" "photo magenta" red and green for a total of eight), both the printer and the software that drives ...
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