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34

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, ...


21

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 ...


14

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 ...


13

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 ...


13

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 ...


12

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 ...


10

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 ...


10

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 ...


10

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, ...


8

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, ...


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

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 ...


7

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 ...


7

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 ...


7

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 ...


7

It's common to refer to these elements as "registration marks" but that's not completely accurate. There are multiple components: Registration marks: thin lines/circles on multiple axes to detect misalignment between color plates. This is what the "Registration" swatch is commonly used for. Color bars: solid and screen value blocks of color (sometimes ...


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. ...


6

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 ...


6

Firstly, when you change color modes, you should use Photoshop's Edit->Convert to profile function. This will allow you to map the colors to the new profile in the least-obtrusive way. This should prevent the logo or other asset from noticeably changing colors. Secondly, the reason people do print designs in CMYK is precisely because it allows them to work ...


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

Here is a rule. If you follow it, you will be loved by your print providers and you clients! RULE: Always ask your printer (or magazine, poster or billboard publisher) for their PDF specifications before submitting artwork for print, and any other specs they might have for a particular type of job, and use their specs to the letter. A good prepress ...


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 ...


5

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 ...


5

Generally speaking, once you have "lost color accuracy" by converting to a smaller gamut, there really isn't any good way to do the reverse and increase your color accuracy by converting to a larger gamut. This is generally why I'm part of the camp that advocates working in the largest gamut you can (even if your screen can't display all the colors), as you ...


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

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, ...


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 ...



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