100% Black to 4 Colour Black

j4yt33

Member
Am I doing something wrong?
I am simply trying to take a customer supplied artwork, open it in Illustrator and assign an ISO Coated V2 (Fogra 39) profile to the file.
Although this sounds very simple, I am having issues with my blacks. All 1 colour Black gets converted to 4 colour Black.

Obviously this is a problem when the job has been quoted for 1 or 2 colours and my profile is converting it into 4 colours.

I am using the ISO Coated profile downloaded from eci.org

Is this normal? How do I get around this problem?

Any help would be greatly appreciated

Many Thanks
James
 
I think that is an RGB default profile setting I think you go into the preferences and change it over to CMYK and that should take care of this. let me know if this works.
 
Is the file an AI or PDF file? If PDF, was it created in Illustrator with the “preserve Illustrator editing” feature selected?

Do you receive a message asking you to select either RGB or CMYK mode when opening the file?

The assign command is simply a “label”, it does not convert/change colour modes or colour numbers – so the conversion must be happening elsewhere.

Why do you need to assign the ISO CMYK profile to say a 1 or 2 colour job?


Stephen Marsh
 
Last edited:
Under Preferences > Appearance of Black the default for Printing / Exporting is set to "Output All Blacks As Rich Black". Try changing that to "Output All Blacks Accurately".
 
The reason for wanting to assign the files with ISO Coated V2 is because we are now using GMG for our colour managing and our standard is now Fogra 39.

For this particular test I am opening an ai file into illustrator that has an old profile assigned to it.

I then select the option to 'Convert documents colours to the working space' which is ISO Coated V2 (ECI)

Then it opens in illustrator, but the 100% Black gets converted to C 76.17, M 68.36, Y 63.67, K 78.91.

My user preferences is set to 'Output all Blacks Accurately'

I hope this all makes sense.
 
The reason for wanting to assign the files with ISO Coated V2 is because we are now using GMG for our colour managing and our standard is now Fogra 39.

For this particular test I am opening an ai file into illustrator that has an old profile assigned to it.

I then select the option to 'Convert documents colours to the working space' which is ISO Coated V2 (ECI)

Then it opens in illustrator, but the 100% Black gets converted to C 76.17, M 68.36, Y 63.67, K 78.91.

My user preferences is set to 'Output all Blacks Accurately'

I hope this all makes sense.


Converting is different to assigning. Assigning is just a tag/label/metadata – while converting changes a files numbers.

As the PCS used in a profile is Lab, source values are not maintained in the conversion, the Lab equivalent values of 0cmy100K with the old profile are mapped to a similar Lab value in the new profile space using CMYK values as that is all the profile knows/understands.

Short answer is this is to be expected when converting using a CMYK profile.


Stephen Marsh
 
Could this just be a simple thing like the document colour mode in illustrator is set to RGB? We have had customer files sent that way, everything looked fine in Illustrator, CMYK, 100% black but when imported into indesign it went CMYK, turns out they had not changed the colour mode to CMYK. A simple click and everything was perfect.
 
wonderings, it sounds like expected behaviour, a CMYK to CMYK device ICC profile conversion will not respect the original CMYK values. All it simply does is try to maintain the Lab appearance of the source CMYK values as the same/similar Lab appearance using the new CMYK values generated by the profile. Whether the source is RGB or CMYK, when a user selects to convert colours the profile takes over.

This is a workflow issue.

Does a proofing RIP need an assigned/embedded/tagged profile in the source file? Most of the time no. This step could be skipped for proofing.

Does a colour conversion need to happen before the proofing RIP? Probably. So where to make the conversion? In the native art (Illustrator or InDesign etc) or in a PDF created from the native art that is then proofed and output?

James, are all arwork files Illustrator, or do you also have InDesign or other native art files?

Do you output PDF files for proofing, plating/output etc?

Do you have PDF workflow software such as Kodak Prinergy, Fuji, Agfa, Esko etc? Do you have Acrobat Pro, PitStop Pro or Server?


Stephen Marsh
 
Thanks for all you feedback.

I understand the new CMYK values will only maintain the LAB values and not respect the original CMYK values. I just feel surely this is an issue that other printers have had that they have worked around.

Stephen, you nailed it on the head for me with questioning at what stage I make the colour conversion. This is also what I am having trouble with.

We open all supplied artworks (mainly pdf's and ai files) within Illustrator to work on. We then output a pdf proof to send to the customer. Once approved, artwork gets stepped up and sent to our digital presses/Conventional Plate makers as pdf/LEN files.

All this is automated as much as possible using an Esko Automation Engine Workflow.
 

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