idealliance g7 process control

[c.pfaffenbichler]

G’day! 

When I work in prepress I primarily work for european printers, but recently we have had to provide CMYK-separated images for U.S.-printers. 

One of the printers had emphasized that they employ G7 and a definitive answer on a target Color Space/ICC Profile was not very easily obtained. 

Idealliance themselves state that G7 should be combined with ICC Color Management … but I am confused as to what that ultimately means concerning hard proofing (with GMG Color Proof on an Epson in this case). 

Should a certified proof (SWOP, Gracol, …) be reproducible in print or does G7’s apparant focus (Neutral Print Density Curve) mean that the Lab target for specific CMYK value-combinations may acually be »overridden«, so to speak? 

Does G7 amount to an additional pillar for Color Management (as set forth by the ICC) or to an ideally parallel but potentially (slightly) conflicting procedure? 

May my confusion just be the result of a misunderstanding based on differing traditions or terminology? 

Regards, 

Pfaffenbichler 

[Bob_Hallam · Accepted solution]

There are a lot of G7 "certified" printers in the US but most of them only know what they remember from their class and have very little experience.  That is the croud your dealing with.  The official ISO color standards are the CRPC profiles available on color.org.   So if your printer does not know what profile they are using or which color space they print in, you can figure out what solor space they "Should be"  printing in by knowing their print process.  Sheetfed Offset, Wide Gamut Digital, Web Offset, white paper, or Web Offset yellowish paper, or Uncoated, or Newsprint.  That print process information can allow you ( or anyone else) to figure out what the printer is supposed to do.  

G7 is another Pillar, different but very similar to the printing process for Fogra coated for example.  The difference is very slight in the highlight areas, if your being picky.  In reality what qualifies for Fogra coated will print very closely to G7 coated CRPC6.   The Advantages of G7 over the european standards is it's paper relative.  Now an argument can be made for color standards that include papers, but todays papers mostly change via optical brightners, so that is not a simple calculation.  

Not quite sure what you mean by "overwridden".   once a file is in a CMYK colorspace / profile is is only correct for that specific colorspace.  So make sure your file workflow includes the correct US profile and embed it in the files.  

[c.pfaffenbichler]

@Bob_Hallam , thanks for your time and effort in replying! 

[NB, colourmanagement net]

@c.pfaffenbichler  As I understand it from guys I know at FOGRA/UGRA/BVDM, the GRACoL ICC profiles were made from slightly "early release" FOGRA/UGRA/BVDM gathered press characterisation data.

Who knows why.

That said, if the printer is working to G7 properly, as he was set up, then one of the GRACoL profiles (the correct one for the print process type, of course, as Bob described) should proof with good accuracy. GMG Colorproof is an excellent product in this sphere, as I am sure you know.

I'd get GMG to put a 'queue' on the RIP for GRACoL - GMG techs will help you to understand more about this.

FYI. My UK GMG Colorproof clients who are on GMG Software Upgrade Contracts get this "add a queue" service from GMG no problem. You just have to know which GRACoL you need.

I hope this helps
neil barstow, colourmanagement net - adobe forum volunteer - co-author: 'getting colour right'
google me "neil barstow colourmanagement" for lots of free articles on colour management