Convert images in a PDF with adjustment

roel78

Active member
I get a PDF-X4 with a FOGRA39 output intent from a client. I always do 3 actions to convert the PDF to improve the images for printing in offset.

1. Convert all images to AdobeRGB with a Acrobat preflight.
2. Apply a RGB-curve to all RGB images with a PitStop-action.
3. Convert all images to PSO Uncoated v3 with a Acrobat preflight.

Is there any way to do all these 3 steps in one automated action in Pitstop or Acrobat. I use Agfa Apogee as a RIP. Unfortunately the client only wants to send us PDF-X4 files with CMYK images. The second step to apply a image-adjustment on the images is also necesarry.

Thanks in advance for your help.
 

Joe

Well-known member
You can do steps 1 and 3 with Pitstop also and then combine all into one action.
 

roel78

Active member
Thanks for the reply Joe. Is it only possible with the PitStop colormanagement preferences?
Or is it possible to convert the images to RGB relative colorimetric and do the conversion to CMYK perceptual in one action? I also want a action for uncoated and coated so I don't want to use the Pitstop preferences.
 

abc

Well-known member
With PitStop you can override the color managment preferences within an Action List, so you can change an adjust the source/destinations if you wish. I think that will solve your issue?
 

Joe

Well-known member
Thanks for that abc as I knew that was possible but darned if I can find it now. Can you point us in the right direction for that action?
 

abc

Well-known member
Hi Joe. It's the last button type on the right of the Action Lists. 'Settings"

There are three Actions. Override Color Management Settings, Restore Color Management Settings, Save Color Management Settings.
 

roel78

Active member
Thanks abc! I wasn’t aware of the action ‘Override color management settings’. This should do the job!
 

Stephen Marsh

Well-known member
roel78, just to be clear – you are repurposing content that may be intended for the older Fogra39 coated condition, into the new PSO Uncoated v3 condition?

What happens if you do nothing?

Are the PDF/X-4 images RGB or CMYK?

Do you know for certain that the F39 output intent is correct?


Stephen Marsh
 

michaelejahn

Well-known member
Yes, I am also wondering that - if you START with CMYK, and convert to RGB - it is not like you are ever going to get 255 Red like EVER. You reds are already clipped.
 

Stephen Marsh

Well-known member
Yes, I am also wondering that - if you START with CMYK, and convert to RGB - it is not like you are ever going to get 255 Red like EVER. You reds are already clipped.


This should be a moot point, as a standard ICC profile conversion of Fogra39 > PCS > Fogra52 should be visually the same.

So what are the RGB curves achieving, apart from subjective image “enhancement” to make a CMYK image “pop” more in an uncoated space by adding contrast and or saturation edits? An RGB working space has well behaved R=G=B grey balance, plus there are no total ink limit issues to worry about blowing.


Stephen Marsh
 

roel78

Active member
Thanks all for your comments.

This action is for a brochure with a uncoated cover and coated internal pages. The clients wants me to add more contrast and saturation. So I want to do the 'enhancement' on RGB-images. Then do the conversion to PSO Uncoated and PSO Coated.
The PDF from the client is a PDF-X4 with CMYK images and a Fogra39 output intent. So I also want to reduce the total ink limit.

I know that it's better to do the image-editing on the original images, but the client doesn't want to pay for that. I'm not a fan of adjusting the images in a PDF, but for this client it's a 'good' alternative.
 
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Stephen Marsh

Well-known member
Are the CMYK images deviceCMYK or are they tagged with an ICC profile?

Although intended for blind exchange, do you know for a fact that the F39 output intent is correct? Until we have new PDF standards in the wild, there is only one output intent, so what is the assumed CMYK source ICC profile for the uncoated work? If the inners are F39 and the cover is uncoated, is the F39 output intent correctly describing only the cover, or is it also correctly describing the inner pages as well? Is the entire PDF separated for coated conditions, or a mix of uncoated and coated and the output intent is muddying the water?


Stephen Marsh
 
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roel78

Active member
Stephen, I get one PDF file for the complete brochure. The cover should be printed on uncoated paper and the inner pages on coated. The images in the PDF are CMYK without a ICC-profile tagged.

The thing is:
- The client wants me to adjust the images, so add contrast and saturation.
- I want to reduce the TAC. Although F39 is correct for coated paper I prefer the PSO Coated v3 which has less TAC.
- For the uncoated cover I want to use PSO Uncoated v3. I split the supplied PDF in two parts of course.

I use the Pitstop actionlist in my Agfa Apogee workflow, so I don't have to run the actions manually.
 

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