How to hide the CMYK channels of only one layer?

[yankleber]

I am preparing a book cover to be printed at a CMYK offset printer. I would like to remove the magenta, yellow and cyan from some black elements (like text and the folding marks that I am going go add manually) in order to leave only 100% of Black.

In the past I have done this by importing the whole cover without those elements into a drawing program such as Corel Draw and then adding the black elements in the program that allows me to control the amount of ink on them, and so it was just to set black to 100% and the other three colors to 0%.

How I suppose to do this in Photoshop CS6?

PS: If someone is thinking about to ask me 'why do you want to remove the other colors?' the answer is that the printing service managers where I live are always complaining that the match of the 4-color on small black texts is a pain in the neck and that the CMY colors doesn't represent an improvement on black texts anyway. And I really have to agree with them. I should also mention that I live in Brasil and here we still have a LOT of print shops running over 60 years old Heidelberg machines where you make adjustments by untightening screws, moving the plates by a tick of a millimeter using hands while you hold the breath and then finally tightening screws again.

[D Fosse · Accepted solution]

You simply cannot have text in 4 color black, it's a registration nightmare. This is a given when you prepare documents for offset press.

Which is why Photoshop is the wrong application for this. This is what InDesign is for.

If you have to use Photoshop, target the black channel and then type. Or you can delete the content in the CMY channels afterwards. This is very simple, just target the channel and fill with white. Done.

If you create this in CMYK, you also need to be acutely aware of total area coverage (TAC). If you exceed maximum total ink, you get smearing and drying problems, and the printer will not be happy. Get the correct CMYK profile for the actual process and find out what TAC is for that specific profile.

I mention this because CMYK can be a can of worms if you don't know precisely what you're doing. By the sound of your post you may not quite be there yet. Work with your printer. Get the right profile.

And next time, do this in InDesign.

[yankleber]

Thank you very much for the heads up D Fosse!

I do graphic design for offset printing since a LOT of time (almost 30 years) and I always used Corel Draw for this as I mentioned before: I just make the imagery part (along with effected text) on Photoshop and then import it into Core Draw and do the texting in it because Corel allows me to remove the CMY from black elements.

This time I was a bit lazy and imagined that Photoshop allowed this level of control and that I only didn't know how to do that.

Now I know that it doesn't and that I just should keep doing things the same away I have doing for decades!

NOTE:

Man, I really hate InDesign...

I have used it a few times but definitively don't like it and every time I have to compose a book, booklet, magazine, anyway, any multipage document I run to the grandpa of desktop publishing: PageMaker! And I still use the version 6! I am SO used to it that it's as if it was in my veins. The only problem is that it doesn't works well on newer versions of Windows so I have to keep a virtual machine with WXP just for this. I think I am a dinosaur. LoL.

[rob day]

This time I was a bit lazy and imagined that Photoshop allowed this level of control and that I only didn't know how to do that.

I agree with D Fosse, if you have to do a lot of this InDesign is worth learning.

If you have to use PS as a layout app, you can set type as 0|0|0|100 CMYK as long as your document's color space is CMYK, but usually it is better to edit in RGB mode and convert to the press CMYK space, because of TAC and black generation issues. You also want to keep the text as a type vector layer so the document can be saved as a PDF, where the text doesn't get rasterized.

If you can keep your text in a top layer, you can edit in RGB, merge the bottom layers, convert to the destination CMYK space, and edit the text layer's color to 0|0|0|100. So:

RGB layers

Duplicate the doc and merge the bottom layers

Convert to CMYK, select the text and edit the text layer's fill color to 0|0|0|100:

By default the black only text will knockout

If you want it to overprint set the text layer to Multiply

[yankleber]

Thanks Rob, yeah, I could have done this, it totally failed to come to my mind!

Anyway, I just finished transferring the art to Corel and now the job it's done.

Nowadays I don't do anymore a lot of this as I used before. Until 10 years ago or so I did desktop publishing for living and there was at least 5 books or more at once at my plate but now it is very rare because I moved to a different direction. I have done lots of commercial graphic design (ad artwork) with very rare small black text for American clients so I just do everything in Photoshop and send the PSD to the print shop (in USA) and in the last 5 years I didn't get a single complain. I don't know if they use a computer registering system or if they print in digital machines.

I have the text of this book to make (the author just sent it to me) but it will fall into Pagemaker, generate a hi-res PDF file and let the print shop resolve the page imposition.

I have used InDesign in the past for a couple jobs. As far as I can remember it was for some clients that WANTED it in InDesign. So if I was going to use it I wouldn't really need to learn it. Actually around 15 years ago when I taught graphic design on a computing school I have given classes of it (version 1.5 - I have no idea in which version it is now). But the fact is that I really don't like it. So I think I will pass InDesign a bit more.

Thanks for all the info!

[rob day]

The job would have to go pretty far off register for someone to notice, and then they would have to care—two unlikely events in the current print world.

One problem with .PSD is its vector type layers will get rasterized and flattened if it is placed in a pagelayout and exported to PDF, the printer probably doesn't print separations from Photoshop. So saving as PDF/X-4 out of Photoshop will prevent that from happening.

InDesign is at version 13.

[Martin_Bns]

You can't do that. When u're in channels, you see the channels of the whole document buddy.

Cheers,
Martin

[rob day]

Hi Martin, I think the question is: can you set black text that will output only on the K plate with no CMY values? You can't do it in RGB or Lab mode because you would normally get a 4-color black on a color conversion, but you can set type as black only in CMYK mode.

[Stephen_A_Marsh]

I’d just like to add that I agree with previous comments that standard ICC profile colour conversions in InDesign will convert 0r0g0b text as four colour black… However, this is a good example of when not to use InDesign for colour conversion. I generally prefer to do no colour conversion in InDesign and do any necessary conversions in Acrobat Pro.

Acrobat Pro can convert 0r0g0b elements to 0cmy100k – including text layers from Photoshop PDF files:

Prepression: Acrobat Pro – Converting RGB Black PDF Content to CMYK Black

And if you have Enfocus PitStop Pro or PitStop Server, an Enfocus Preflight can convert such content using a special ICC DeviceLink profile, that will map 0r0g0b elements to 0cmy100k.

And if you or your printer is using a specialised PDF prepress workflow software system such as Kodak Prinergy – then that too will convert 0r0g0b PDF elements to 0cmy100k.

[yankleber]

So are you guys saying that is safer to send the file in RGB instead CMYK?

[Stephen_A_Marsh]

yankleber  wrote:

So are you guys saying that is safer to send the file in RGB instead CMYK?

I can’t speak for Rob, however I for one am NOT suggesting that you send out text in RGB to an unknown supplier.

Text/vectors vs. RGB images are different beasts!

I was noting that there are many ways to deal with RGB text and make it K only of CMYK, if one has the correct tools and knowledge to use them correctly. So keeping the text as RGB is just a short term means to an end, not the end in itself.

However if the printing is “digital” and not traditional separations based, then there should be no major issues with the text being RGB or four colour CMYK.

[D Fosse]

yankleber  wrote

So are you guys saying that is safer to send the file in RGB instead CMYK?

All of the above techniques described by Rob and Stephen are good workarounds if you have to do this in Photoshop. But I think we all agree that Photoshop is the wrong tool for this.

[rob day]

I’d just like to add that I agree with previous comments that standard ICC profile colour conversions in InDesign will convert 0r0g0b text as four colour black…

But if you were using InDesign, wouldn't you set the text in the page layout? I would place the background art as RGB and set the black type as CMYK in the layout, which would eliminate all of the fussy steps in my #3. On export I would have the option of converting the RGB background image to the document's CMYK profile without affecting the black text—or I could leave the color unchanged and let the printer handle the conversion.

[Stephen_A_Marsh]

Agreed Rob, if you have control of the content and the text is native to InDesign, I would make it K only and not RGB. My comments were in relation to supplied placed content that one has no control over.