Where are my blacks in CMYK?

[TheDigitalShaman]

Hi,

I have nearly no experience working with CMYK.

I have my artwork. Made in RGB. COnverted to CMYK. It looks dull and foggy.

What would be the first thing to do? Open a curve or add curve adjustment layer.

The thing is, I cant get my blacks this way! What is that I dont understand? WHy by clipping tones with curve, i am not getting my black in CMYK? It gets darker only to some point (dark grey at best) and goes no further.

Please let me know what I am missing here.
Thanks,
Artur

[Derek Cross]

Don't convert to CMYK, keep in RGB color mode and, probably for most purposes, choose sRGB color space.

(Note the RGB colour gamut is far larger than CMYK, so colours like bright greens and bright oranges will always be duller in CMYK)

[jane-e]

Adding to what @Derek Cross said, don't convert back to RBG (sic), as it won't bring the colors back. Hopefully, you converted on a copy and still have the original and can use that. Tell us why you thought you needed to convert and we'll help you there.

~ Jane

[TheDigitalShaman]

How to bring blacks in CMYK for printing? When I converted RGB to CMYK its super dull and curves dont work.

[Derek Cross]

As mentioned, don't convert to CMYK.

Are you printing to your own desk-top printer, a photo bureax or using them in a desk-top publishing application (such as InDesign) for commercial litho printing?

[TheDigitalShaman]

I need to deliver it in CMYK for commercial printing purposes.

[D Fosse]

You don't understand. CMYK is strictly for commercial offset presses (books, magazines etc. in large print runs). The only time you need to work in CMYK, is if you're preparing press-ready material that will go straight to press.

For anything else, work in RGB. Inkjet printers are RGB devices that expect RGB data. These printers have more than four inks, so a 4-ink separation makes no sense anyway.

Go back to your RGB originals.

[jane-e]

Even when going to press, the conversion should be done on export, as described in this article from InDesign Secrets:

https://indesignsecrets.com/import-rgb-images-indesign-convert-cmyk-export.php .

~ Jane

[TheDigitalShaman]

So everything for printing is prepared in RGB and converted at the very end? Is that the common practise?

[TheDigitalShaman]

Yes, this is what I need it for.

Need to prepare artworks for commercial printing. Some of them art made in RGB, some in CMYK. I can't get my blacks in CMYK though.

[c.pfaffenbichler]

You keep saying you »converted to CMYK« but you don’t seem to mention which CMYK. 

So: Which CMYK Space did you convert to and what was the image’s original RGB Color Cpace? 

[c.pfaffenbichler]

Please set the Status Bar to »Document Profile« and post meaningful screenshots. 

Does the artwork feature fine black linework ot black type? 

[TheDigitalShaman]

Hi.
Thank you for the reply.
Yes, it does feature black lines and black fonts.

I tried many color spaces. For instance: Coated FOGRA39.

[NB, colourmanagement]

The Adobe made profile [created from the ECI characterisation data] called 'Coated FOGRA 39' has the ability to print good blacks with no issues.

If a file contains black lines and text and is in RGB then there is no "K", no actual black there, just density, let's say 0,0,0 RGB.

If you convert that RGB file to CMYK then the areas that were 0,0,0 RGB will be 4 colour. Not pure K. 

Is that what you are seeing as a problem? 

If so, its best to add black lines and text after you converted to CMYK.

Or is it that images with good black tones are no longer showing that black density when converted to CMYK? 

If the latter it could be due to the difference between screen black at 0,0,0 and predicted print black - ink on paper is nowhere near as black as 0,0,0 appears to be on a screen.

I hope this helps

thanks
neil barstow, colourmanagement.net :: adobe forum volunteer
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[Derek Cross]

You keep in RGB for all these outputs:

Desktop printers use their own sofware to convert from RGB to CMYK or CMYK plus; Photo Bureax (mostly) want sRGB and commercial litho printers use (mostly) RGB images converted via PDF/X-4 to a CMYK that suits the substrate they'll be using.

(and if you also use these images for websites etc, they'll need to be in RGB)

[c.pfaffenbichler]

If the images are really going to be printed in CMYK there can be cases (for non-photographic stuff effectively) where it might make sense to print thin black lines or texts as 0/0/0/100 to avoid registration issues, but this can lead to other issues (like inadvertently knocking them out from backgrounds) … 

[PECourtejoie]

Yes, please read the indesign mag article, and answer the various questions asking you which profile you are coming from and to, and why do you convert to CMYK.

[NB, colourmanagement]

Artur, What's really important here is WHY are you converting to CMYK.

IF you have been instructed to do that for an offset or maybe flexo print job, what CMYK ICC profile you have been asked to use.

There's is no "generic" CMYK, you need an exact ICC profile specification.

You ask about the K in the CMYK - that is created by the black generation curve in the CMYK ICC profile which will also contain info about GCR / UCR.

Areas which could be created with [effectively] equal densities of C,M&Y can also be made with part of that "grey component" replaced by K. Now less ink is used and the on press colour balance is more stable.

Making press ready CMYK is quite a responsibility.

There was a time when it was a job done by "scanner operators" with a very high level of skill and pay packet / holiday package. Then along came Photoshop and nowadays it's discussed by many as if making CMYK was as simple as switching on a light. 

You need a compelling reason to make the conversion, and if you have to do it you may need some training [or at least practice] on pre conversion optimisation (of the RGB) and then possibly on optimising the converted file too.

I hope this helps

thanks
neil barstow, colourmanagement.net :: adobe forum volunteer
[please do not use the reply button on a message within the thread, only use the blue reply button at the top of the page, this maintains the original thread title and chronological order of posts]

[TheDigitalShaman]

Thank you a lot for the reply.

Converting all the info into last simple question.

I am the guy who makes artworks for commercial printing. I need to provide it to the DTP guy.
Should I prepare it in  RGB and allow him to convert it to CMYK?
Why he has no idea about RGB and requests CMYK? It makes no sense in comparison to what you say.

My take is that. Myself, as a digital artist, I shouldn't even be requested CMYKs from guys who will prepare it for printing.

[c.pfaffenbichler]

»My take is that. Myself, as a digital artist, I shouldn't even be requested CMYKs from guys who will prepare it for printing.«

Obviously it depends on what imagery you create and how would we know that? 

Are the images photographic or illustrative – if the latter do they feature fine linework and lots of primary and secondary colors or are they more painterly? 

[Bob_Hallam]

So the assumption by some is that RGB is RGB and CMYK is CMYK, but that's not the case.  What RGB profile is in use is important.  What CMYK profile was used to convert to?  Was that the correct profile for the printing process?  If you choose an uncoated profile it prints with very low densities and will appear washed out, but if you convert to a coater paper profile it will not.   Just depends on how the job is going to be printed.   Some details about what you tried will go a long way in helping this community help you with this issue.