Text an QR-Code black is multicolor in CMYK

Retrobatch
1

Hi, I have a wonderful workflow that adds text and a qr-code to images. But when converting to a cmyk profile (FOGRA39) all black gets converted to multicolor and not just 100% Black. I already tried to make the color conversion early in the flow and set the text colors with an cmyk slider to 0-0-0-100 but that doesn’t help (despite there is no way to choose a QR code color). Printer says, he cannot print black text or QR codes that are 91 % Cyan, 79% Magenta, 62% Yellow and 98 % Black…

Is there any workaround for this problem? Or maybe a chance to get the internal flow set to the selected profile? That would really make a difference for a professional tool…

Thanks for any help…

2

I’ve been playing around with this profile a little bit this morning, and it just doesn’t seem to want to convert RGB black to 100% K (Retrobatch is using Apple’s libraries for doing the conversion).

I’m curious, what tool would you normally use to convert RGB to CMYK in this instance? I’m also trying out Photoshop to covert sRGB to FOGRA39, and the K value is showing up as 98%.

3

Hi August, in Photoshop I would do a profile conversion with an own profile with GCR and maximum black. But I found out, that “PSO coated V3” with render intent “saturation” does the job quite well in photoshop. But when trying that in retrobatch, the black keeps 4C…?

Would it be possible to add cmyk colored text and images after a profile conversion in retrobatch? Or is the engine internally RGB?

4

Played around with the render intent but that seems not to touch the colors at all? At least my black always has the same values whether “Absolut” or “Saturation”. There should be a difference, shouldn’t it?

5

…and when inputting a cmyk image and adding a text with “0 0 0 100” with the CMYK sliders, the output is again “91 79 62 98” even with no color conversion at all…

6

Do you have the “Photoshop 4 Default CMYK” profile? That seems to do the trick for me. The “Photoshop 5 Default CMYK” profile also does it correctly.

7

Sorry, that did not work for me, the black is then 100 % but also still c m and y about 60 to 70 %. Have workaround by using a AppleScript that starts a Photoshop action that converts it to 0 0 0 100

Here ist the Script, just wanted sure, if anyone else need to call a photoshop action from retrobatch:


using terms from application "Retrobatch"
	
	(*
	The processStart handler is called when your workflow has started running
	*)
	on processStart()
		
	end processStart
	
	(* 
	The processAsset handler is called for each image asset that passes through this AppleScript node
	You can return a boolean value that says wether or not this asset should continue on through the next node(s)
	*)
	on processAsset(anAsset)
		
	end processAsset
	
	
	(* 
	processEnd is called when your workflow is about to end
	*)
	on processEnd()
		
		--Need to use Applescript file paths with colons for Finder
		set sourceFolder to "Macintosh HD:Users:frank:Documents:TEMP:COOKED:Muster"
		set destFolder to "Macintosh HD:Users:frankzoephel:Documents:TEMP:COOKED:Muster"
		--source and destination folders for the images
		tell application "Finder"
			set imageSet to get every file of folder sourceFolder
		end tell
		
		tell application "Finder"
			repeat with i from 1 to (count of imageSet)
				set currentImg to (item i of imageSet) as string # coerce Finder style path to string
				tell application "Adobe Photoshop 2025"
					activate
					set ruler units of settings to pixel units
					open alias currentImg # for Photoshop, need to coerce it back to alias!
					
					do action "Grey>GCRmax>FOGRA39" from "Graustufen zu FOGRA39"
					save current document in destFolder as TIFF with options {class:TIFF save options, byte order:Mac OS, embed color profile:true, image compression:LZW, save layers:false}
					close current document without saving
					
				end tell
			end repeat
		end tell
	end processEnd
	
end using terms from

If anyone is interested, I can share my PS action to convert from FORGRA39 cmyk to full black also here…

8

But anyway: a constant cmyk workflow would be great… Because when just reading and writing the files it keeps the colors, but when adding eg. a image grid to combine 2 of them the colors get converted again to 4c black… will try with image watermark…

9

I’m glad you got something figured out. And I’ll see if I can make it do what’s expected in the future as well.

I forgot to answer this part! Yes, the engine internally is RGB (for the most part). There are some node combinations that should keep everything CMYK, but if you’re doing any pixel operations then it’s going to be converted to RGB first.