Thursday, April 1, 2010

Question about true black

Ok, I understand that for print, it is best to use a ''true black'' for cmyk color. What I don't understand is how to set Photoshop, Illustrator, and InDesign to convert all blacks to true blacks, so I don't have to worry about it when i'm working in a cmyk document. Is there a way?



I know in Illustrator there is an option to select ''print all blacks as true black'' (even though I don't know what Illustrator considers true black, since some use 50,40,40,100, some use 40,30,40,100, and so on)...so why doesn't Photoshop have this option when working in cmyk?



Here is an example of why this confuses me...Lets say I'm working in Photoshop and I have a bunch of graphics (some imported and some created)..I have to manually go and check to make sure that all of these graphics are using my choice for true black (50,40,40,100). Why can't photoshop automatically apply my true black when i'm working in cmyk? I'm just worried that I may look over some of the graphics that are in regular black, because they will print in a different shade than the true black. Photoshop's cmyk black is set to: 75,68,67,90...why? I've never read to pick a true black that doesn't have 100 for the last number.



I just want to be able to not worry about true black...and tell Photoshop (or any other Adobe program) to automatically convert all colors in black to a true black. Am I missing something here, or does it have to be this confusing and worrysome?
Question about true black
''True black'' is not an appropriate expression. You mean ''Rich Black'', in which a boost value of some or all process colours is added to 100% black.



There is no simple way to tell Indesign or Illustrator to convert all 100K blacks to Rich Black, and thank Gods! You don't want to use rich black for body text or most rules.



Photoshop converts all blacks in grayscale or RGB to rich black based on your colour profile. You can fine tune that amount using a custom CMYK setting. Edit %26gt; Convert to Profile, click Custom CMYK, then play with GCR/UCR and Black Generation.



But Photoshop assumes it is working with photos, not precisely defined graphics, so RGB black (0,0,0) won't be converted to rich black, but to a more photographic black that's appropriate to the image as a photograph. In almost all cases, that's a good thing.
Question about true black
I generally want to choose what my rich black will look like. There is no ''rule'' that states it has to be perfectly neutral. It can be a warm black, a cool black, a reddish black, a greenish black...you get the idea -- depending upon what best enhances the nature of the piece you're working on. You probably want 100K -- but even that is not an absolute. Add C, M %26amp; Y to bring up the tone and density, keeping the total percentage of the four colors to around 300% (depending upon the press, pressroom environment, ink and stock being used).



I found that a good way to visualize what a particular rich black will look like is check one of the Pantone CMYK color swatch books (coated, uncoated or matte stock, as appropriate), and spec from there.



Neil

As Scott says, you almost never want fine linework or black type. Even B%26amp;W half-tones may not be best in a rich black (consider duotones or other combinations of CMYK).



Neil

As Scott says, you almost never want fine linework or text-size black type printing in rich black due to registration issues resulting in color fringing. Ideally, keep small colored type restricted to two-color combinations. Even B%26amp;W half-tones may not be best in a rich black (consider instead, duotones or other combinations of CMYK).



Neil

Thanks for the replies. It helped some. Neil, I'm not quite sure what you mean by ''keep small colored type restricted to two-color combinations''.



Is it safe to say: use regular default blacks for any fonts/text...and use ''rich black'' for large, fat font/text? If this is a good rule of thumb, then does it apply to both Illustrator and Photoshop?



Neil, regarding the pantone color book; I really need to get one.



Scott, thanks for mentioning the cmyk custom settings. I've used the ''convert to profile'' but never created a custom setting. I'm going to have to find some tutorials on that to learn more.

GYG,

%26gt;keep small colored type restricted to two-color combinations



By using only two of the four process (CMYK) colors to colorize type, you reduce the chance of misregistration during printing. So, for example, you might construct a blue out of 100C + 40M.

%26gt;use regular default blacks for any fonts/text...and use ''rich black'' for large, fat font/text?



Keep 'em black only.

%26gt;regarding the pantone color book; I really need to get one



Take a look at the Pantone Color Bridge/coated, uncoated set. It's a good starting point.



Neil

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