GCR and Profile conversion in Prinergy

[rickyticky]

We have Prinergy Connect Version 5 workflow. We currently use the colour settings shown in attached file (Current.pdf) which converts CMYK images and graphics from ISOcoated_v2_eci.icc to ISOcoated_v2_300_eci.icc. This is mainly done to control TAC (also saves us on average 3% ink usage).
What we are looking to do is change this setting as can be seen in attached file (Proposed.pdf) so that we convert images and graphics from ISOcoated_v2_eci.icc to coated_FOGRA39_GCR_bas.icc. I have tested this through the workflow and got as far as proofing but not had the opportunity to run press tests yet. We are seeing an average ink reduction of 10.5% which we are very happy with as it does not involve any financial outlay which is out of the question at the moment. We have visually compared the proofs, and measured lab values in certain of the files and are very encouraged, but I feel we are missing something as this seems to easy?
We would only carry this out on selected PDFs that we know have been created to our usual spec (generally PDFx-1a with an ISOcoated_v2_eci.icc output intent) so in my understanding the conversion should be OK. Is this the case?
Also other elements are not affected (text, frames and fills,etc....)

One more quick question, I believe the ISOcoated_v2_300_eci.icc profile has some sort of GCR in it but I cant find the details on this do you know?

Thank you for taking the time to read this

[dherder]

If you perform this refine, you will reseparate all cmyk content, including primaries (c,m,y,k) and secondary (cm,my,cy) colorants. The real world implication here is contaminated (hue adjusted blacks, drop shadows, etc.)

For you to take full advantage of ink savings and also ink optimization, it is best to create a constrained DVL that allows for modification of the black start, in addition to the black strength in your black generation strategy. This can be done very well with several software solutions on the market, but seeing that you have Prinergy 5.1 already, the best solution (with full workflow integration) is the ColorFlow option with the Ink Optimizing Solution.

regards,
dave

[rickyticky]

Thanks for the reply Dave,

My understanding is that this is only applied to images and graphics, so it won't reseperate the complete file, I think we may be better just applying to images and not graphics. I agree with you that ColourFlow would be the ideal solution but I'm sure we would be knocked back by the money men if we requested this. if we can be sure original images had an embedded iso coated v2 profile and we are careful with black images converting to 4 col I think it looks an acceptable solution when looking for some ink reduction. We did trial GCR software, (ink optimiser) but were not to happy with the results.

[mattbeals]

You can try using callas pdfToolbox desktop/plug-in or the server version to apply one or more static device link profiles to images only.

Using pdfToolbox we can say:
Rule 1: "apply the device link named ISOcoated_v2_eci to coated_FOGRA39_GCR_bas.icc to cmyk images with the attached profile named ISOcoated_v2_eci.icc".
Rule 2: "apply the device link named US Sheetfed Coated to coated_FOGRA39_GCR_bas.icc to cmyk images with the attached profile named US Sheetfed Coated.icc".

We can add as many of the rules as we want. This list can contain RGB to CMYK or CMYK to CMYK links. Of course you have to build the links and update the rule list as needed. But it is highly effective.