3

Let's say that I have received info that ink limit should be 300% (this might or might not be accurate), but no info about the specific profile. I convert the files to Iso coated v2 300.

What happens, if the print house is using another profile? Does the printer/print process change the ink values in the pictures, or do they remain as they are like I have made the files? Meaning, will the end result be similar that I see in my Acrobat preview?

I understand there could be an issue if there is too much ink (like use fogra39 and 330% when the ink limit should be 300%), but is there a problem this way around?

Accordingly, is there a rule of thumb which CMYK profile to use for a commercial printer when there is no information?

(Background: I might not know where the files will be printed or there might be several printers, so I try to find a best way to work around this)

8
  • 2
    I actually answered this question in my answer to one of your other questions. But you never reacted. Did you read it?
    – Wolff
    Apr 19 at 18:32
  • Yes thank you for your comprehensive reply. The question was indeed overlapping and I didnt remember that you replied to this particular issue as well. So am I reading it correct, the once changed color values of images will not change? Lets say if the print house uses fogra39 and my files are on iso coated. There will be a difference from what I see on my screen, but I’m trying to understand will it be very visible, meaning should I be very worried in a case like this or not. Sometimes it is really impossible to get the actual specs/profiles.
    – Pocket
    Apr 20 at 8:57
  • The difference will be different depending on which profiles we talk about. ISO Coated v2 and Coated FOGRA39 is pretty close, but not the same. Total ink can be a problem so choosing ISO Coated v2 300% is perhaps the safest choice. And then you just have to live with the print perhaps being a little bit paler in the darkest areas if you print according to Coated FOGRA39.
    – Wolff
    Apr 20 at 11:09
  • 1
    You can simulate how a CMYK image will look if printed according to another profile. Take an RGB image and use Edit > Convert to Profile to convert it to for example ISO Coated v2 300%. Afterwards use Edit > Assign Profile and choose Coated FOGRA39. Tick Preview on/off to see the difference. Assigning doesn't change CMYK numbers, only the preview of the colors.
    – Wolff
    Apr 20 at 11:12
  • 1
    Not completely sure about Proof Colors. It depends - so many settings. 😀 I would either use Assign or Proof Colors with Preserve CMYK Numbers to test this. But you have to first convert to a CMYK profile for this to work. Won't work with RGB images. You have to force the "wrong profile error" to happen.
    – Wolff
    Apr 20 at 12:25

1 Answer 1

3

Generally, as a designer, your only task is to let the printer know your working space. Tag or set intent when exporting your work.

  1. If the printer provides, recommends a profile for your job, substrate, design your artwork in that profile. Tag or intent your job.
  2. Unknown printer? Use a generic profile (for offset (Europe) for example Fogra 39, or v2 ECI) and let the printer know your profile used for the artwork (tag or intent).
  3. Device values are meaningless for the printer, they will assign their defaults or ask you about your working space.
  4. A good pre-press will warn you if they see something fishy (extreme out of gamut colors, shifts).
  5. For color critical work request a hard proof from the printer if possible.

"Lets say if the print house uses fogra39 and my files are on iso coated. There will be a difference from what I see on my screen, but I’m trying to understand will it be very visible, meaning should I be very worried in a case like this or not."

In theory, if you set a color in Fogra 39 and the printer assumes a different profile, yes you may see some difference (CMYK values remain the same), but if the printer converts (CMYK values converted) to a different space you would not see much difference assuming both spaces contain the set color in their gamut. If the set color is out of the target profiles gamut you can expect some difference.

Some toughts about Wolff's post since he linked his previous comment.

"A CMYK image is basically just a collection of pixels with each their CMYK values. They can have a color profile embedded (we say the image is "tagged" with that profile), but it's really just a name. The CMYK values have been determined when the image was converted. The profile doesn't do any additional trickery."

Yes CMYK values have been determined... without knowing the profile these device values are useless, you can say it is blue (80C/10M), but what blue is it exactly? The blue your default printing house profile determines or the blue set in the artwork file characterized by the tag profile? Really just a name? No, not really, they help you to know what blue it is in a device independent space.

"All print houses I've ever worked with (including our own) in the end don't really care about which color profile an image is tagged with."

Obviously this is not the way to properly handle color management...

"The CMYK values are used as they are as instructions to which halftone screens to burn to the printing plates. A 50% black simply becomes a 50% halftone screen on the plate. (There is also some calibration curve applied but that should be of no concern for a designer.)"

So if you print 50% black with different black inks made for various profiles visually will you get the same color when printed?

"The printer can't respect other profiles your PDF might have set as intent. And they certainly can't print different elements of your PDF with different profiles."

Sad, so what is the point of tagging and setting intents? The printer can, and some will respect the source profile, because it is a must to do a proper color conversion if needed.

10
  • Youd be suprised how little color management actually happens in parts of the industry. Its mindboggling that a 30 year old tech hasnt been entirely addopted yet. Mostly the problem is on the user side. The problem really arises with out of gamut colors because users allways want the most virant color they can get and then the conversion intent becomes important and that just goes over the head of most people.
    – joojaa
    Apr 22 at 9:32
  • Well, after two decades in the industry, I am surprised at nothing... Lack of basic understanding on the design side, lack of desire to print in quality on our side...
    – Fox123
    Apr 22 at 11:41
  • Hi there and welcome to GDSE! You sound like you work with prepress yourself. I can see that taken out of context some of my quotes might seem a bit questionable. When I say that a print house "don't really care about which color profile an image is tagged with" I simply mean that I've never encountered a print house that actually converts automatically from one CMYK profile to another. Too much hassle and not really our responsibility. 100% black should be untouched, but what about tints of black? What if the images are untagged? etc.
    – Wolff
    Apr 22 at 15:03
  • 1
    "Some printers state in their specs that they don't want the profiles included or some settings won't allow me to set the intent on the pdf. Why is that so?" I assume it is because they do some conversion, and want to avoid the hassle, issues introduced by tagged PDFs in their pre-press workflow. An intent, tag should not be an issue for a proper workflow tho, in fact, certain PDF standards do require a set output intent.
    – Fox123
    Apr 25 at 19:14
  • 1
    ""I have figured out as well ..."First, get information from the printer if possible. If they recommend a working space, design with that in mind, export with output intent, and you are good. If they specifically want an uncalibrated PDF, well you have no choice. Better submit without tag or intent (if they previously gave the profile to work with, you should not expect a big problem). If you can not get any information from the printer use a generic profile (substrate, printing technology), export with intent.
    – Fox123
    Apr 25 at 19:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.