Copy link to clipboard
Copied
Hello again!
I'm still working on these childrens books, and here's where I'm at.
I calibrated and profiled my monitor and the client's monitor.
The client has been merrily filling in the black outlines of her drawings in Photoshop. She picks the CMYK swatch that looks good on her monitor and fills in the drawing.
Now, I have on my computer a copy of her monitor profile. When I open her PSD images (which are in CMYK mode, with a generic coated SWOP profile), it seems to me that I should:
(a) discard the attached profile, preserving the CMYK numbers
(b) convert the image to the RGB profile of her monitor
(c) convert the image to the CMYK profile of the printing press (or perhaps back to a generic CMYK profile, since we don't yet know where we're printing).
Is this correct?
Or perhaps, when I open her PSD images, I should
(a) use the embedded profile (US Web coated SWOP)
(b) convert to the destination profile of the printing press
Any guidance appreciated,
Ariel
Copy link to clipboard
Copied
Hold on, I got that wrong. Dot gain doesn't pass the the Preflight. I'm
getting "Document generated more than one plate" even with the output intent
embedded.
Copy link to clipboard
Copied
Arïel wrote:
Hold on, I got that wrong. Dot gain doesn't pass the the Preflight. I'm
getting "Document generated more than one plate" even with the output intent
embedded.
What preflight are you referring to? Acrobat Preflight?
What program generated the registration? Is it marks from InDesign?
Copy link to clipboard
Copied
Ariel
I have replicated your problem with registration color but the conditions are probably not the same.
Illustrator PDF with registration element. The color is converted to Dot Gain 20 Output Intent as previously mentioned, in Acrobat. Then the PDF is opened in AI again, and the Acrobat conversion gets discarded.
Illustrator should warn about this, so I doubt this relates to your problem.
The only explanation that makes sense is the PDF is somehow being edited after the Acrobat conversion. Perhaps you are processing the PDF through a separate workflow system (I.e. a RIP/Interpreter), and this system is doing the preflight?
If you do the conversion to gray Output Intent in Acrobat, and preflight for CMY plates immediately afterward in Acrobat, I'm not sure how you get flagged for extra plates. Do you know what application originally generated the PDF? Maybe it has a spot color All, or maybe this is a DeviceN color issue
Not sure about this, wish I could be of more help.
Copy link to clipboard
Copied
Here's a simple test file.
The challenge: Convert it to grey scale in Acrobat.
Success is achieved: if you open Output Preview, hide the K plate, and everything disappears.
Whoever succeeds will be my hero! Use any settings you like.
The test file was quickly created in InDesign CS4: plain blocks of 100,0,0,0; 0,100,0,0; 0,0,100,0; 0,0,0,100; 100,100,100,100; and a green.
Copy link to clipboard
Copied
Actually: success is only achieved if:
You also run Acrobat's own preflight test "Document uses more than one plate" and it doesn't find any problems.
Copy link to clipboard
Copied
Copy link to clipboard
Copied
Wait a minute
For some reason my gray pdf is taking two days to upload. But there is a problem anyway
The problem is I made your 100K = 93K. This works better:
Your PDF has a CMYK output intent. That remains. You convert everything to grayscale, select a gray profile beside "conversion profile"
Also enable preserve black
After this, everything is remapped to the black channel. The CMYK output intent remains. And the document passes the preflight.
I will start another upload but it may take a while
Copy link to clipboard
Copied
Here is new just disregard the first one
Copy link to clipboard
Copied
Rick,
When I follow your instructions, the PDF passes preflight. But in Output Preview, hiding the black plate shows that everything that was printed in registration black remains on the other plates, despite having converted to a grey profile?
I'm not managing to download your PDF yet. This queuing business is a forum bug, I think.
Copy link to clipboard
Copied
OK, we can workaround this without the upload.
My last post I forgot to attach. I started another upload but it was taking to long so I canceled
Refer to this screen shot:
Copy link to clipboard
Copied
Which version is that? 8 or 9? I have heard that later versions have improved the conversion process.
I'm still on version 7.0 and I think it simply cannot be made to work.
Copy link to clipboard
Copied
It is 9. I'm sorry, I thought you had 9 along with IDSC4.
I have 8 but not 7.
Perhaps there is still a workaround, I will think about it.
Does 7 have the preserve black feature?
Copy link to clipboard
Copied
Sorry, I should have mentioned I'm still on 7 (got IDCS4 as a present for beta testing!)
Preserve black does exist. Here's a screenshot of the convert colour window:
Copy link to clipboard
Copied
This is very much like 8.
To get gray select your gray gamma in the destination space.
Do not embed the profile. Preserve black objects.
Convert RGB and CMYK. There is no need to convert Device gray.
Copy link to clipboard
Copied
I did it in 8 and here's the deal:
I got the result you are getting, registration still showing up. Preserve black objects does preserve the 100K.
It also passes the preflight test.
Remember I mentioned spot color All. That's what you've got. I don't think it's a big issue. A RIP will just convert it to gray (100K)
Version 9 has worked out this All bug. But you should still be able to do the conversion in 7, get the satisfactory preflight and just realize you have this strange color definition. How to get rid of it? Not sure at this point. A RIP takes care of it, but I don't know of another way.
Copy link to clipboard
Copied
Thanks Rick.
That's what you've got. I don't think it's a big issue. A RIP will just convert it to gray (100K)
Except if this converted PDF is part of a 4-colour book -- then some objects risk standing out because they're in registration black.
Thanks again for your help.
Ariel
Copy link to clipboard
Copied
Hmmm. What exactly do you want to fix here? Registration is supposed
to appear in all plates thats what it is for. If you want to remove
the registration black areas recolor them as Black (K). Registration
should only be used for Registration bombs and they are usually added
by the pre-press guys once the job is imposed.
Best Regards,
Wayne Pincham
wpincham@bigpond.com
Copy link to clipboard
Copied
If you want to remove the registration black areas recolor them as Black (K). Registration
should only be used for Registration bombs and they are usually added
by the pre-press guys once the job is imposed.
But what if (as it is in my case), the artwork is prepared by someone in one country, the book is laid out by a team of designers in another country, and then I get sent the final PDF and am asked to convert it to greyscale? I check the PDF, and find that occassionally some words are in registration, not black, and some other stuff that clearly should be in black is in registration. I don't have the original InDesign files, and even if I did, the error can sometimes be with the artists in the original country... I've got no way of fixing the original files, and would like to be able to convert everything to greyscale and eliminate registration altogether in the process!
Copy link to clipboard
Copied
This registration color you are dealing with should default to gray in any RIP, even with a CMYK job. I ran the file I converted with 8 through my older 2 layer RIP workflow and it became black only.
I use PitStop and it flags this color as spot color "All". Of course it is not a spot color. It is a global process color, or registration gray, or something ridiculous like that.
There may be a way to get rid of this bug color in Acrobat 7 in the vector PDF. I have looked for a way in 8 but haven't found it yet. I know PitStop converts it to gray.
You may consider upgrading to Acrobat 9...
Copy link to clipboard
Copied
If the PDF is not locked, you can open it with Illustrator and edit
the colour assignments. Then save as PDF.
I get the same problem with spot colours, I have a client that will
colour most of his text as PMS047 and odd words Reflex Blue. These are
the same hue but it screws up the plate out puts. I had to select
every thing that was Reflex and change it to PMS047 with monotonous
regularity, he would not listen to my advice.
Best Regards,
Wayne Pincham
wpincham@bigpond.com
Copy link to clipboard
Copied
Wayne Pincham wrote:
If the PDF is not locked, you can open it with Illustrator and edit
the colour assignments. Then save as PDF.
You can edit the PDFs with Illustrator but you may run into problems. First off you can have font issues. Second Illustrator does not support DeviceN.
Usually it flags for these issues, but you still have to be very careful editing PDFs in Illustrator, you may change things in the file and not be aware of it.
Copy link to clipboard
Copied
Hi Rick
CS4 does support DeviceN
Copy link to clipboard
Copied
InDesign does, but AI and Photoshop do not
DeviceN allows multiple spot colors and process colors to be included in a single swatch. InDesign has multi-ink swatches but AI does not
The only DeviceN images that exist are in PDF output. There is no DeviceN color state in Photoshop. Spot channels exist but these are monotone ride alongs. Duotones are nothing more than grayscale images with transfer curves.
No trying to be disagreeable, perhaps my definition of DeviceN is not the same as yours. All I know is AI does not have multi-ink capability and does not support DeviceN images in PDFs. And in Photoshop there is no color mode DeviceN, or a composite channel that allows for multi-ink (spot + spot, spot + CMYK)
Copy link to clipboard
Copied
Rick,
If you do the conversion to gray Output Intent in Acrobat, and preflight for CMY plates immediately afterward in Acrobat, I'm not sure how you get flagged for extra plates. Do you know what application originally generated the PDF? Maybe it has a spot color All, or maybe this is a DeviceN color issue
Let me try and think more carefully about this.
You are right in that if I take a colour PDF and convert it to a greyscale profile (dot gain or grey gamma) it passes the preflight and in output preview shows only one plate.
But, if in output preview I select a CMYK press profile, and then hide the K plate, I see that the grey is actually composite grey, not restricted to the black plate. This is a problem, because if this greyscale PDF is being printed as part of a 4-colour book, all the text will be rich black?
Hope this makes sense.
Copy link to clipboard
Copied
After converting to gray try this:
Convert to CMYK output intent, preserve black, promote gray
I tried to upload your PDF after I converted but it's taking forever