Colour Management Information from

Graphic Quality Consultancy

Printing Specifications. Part 2 -  ISO, SWOP, etc.

In Part 1 we learned about some of the information which may be contained within printing specifications, or standards. In this article there will be more information about current specifications and older specifications, which may still be in use. There will also be some explanation as to the difference between "Standards", "Specifications" and "Methodologies", and the resulting ICC Profiles. Please note that the actual specifications and profiles cannot be provided here for copyright reasons. There are links to their sites however.

I.S.O.  Many printing industry technical organisations from around the world are now working towards common ISO (International Standards Organisation) standards.  These refer to Paper Types, TVI (Tone Value Increase), SID's (Solid Ink Densities in CIE Lab values), etc. These are frequently updated. They are copyrighted, but you can download the standards from the ISO site for a relatively small fee: ISO 12467-1 for offset printing (you will also need the 2007 ammendment) and ISO 2846-2 for offset ink. Please note that there are many other related standards. Please be aware that they are fairly compex documents.

These ISO Standards are also incorporated in "Specifications" supplied by several of the leading Industry Organisations from many countries. These organisations sometimes supply ICC Profiles to match those specifications. They are often labelled  "Iso...".  The ISO itself does not  supply or endorse Profiles, Proofing systems or individual Printing Companies. Individual Printing Companies can also profile their own presses, which are running to ISO standard, and offer these Profiles to customers. This sometimes happens when they use paper stock which is other than Paper Type 1 or 2, or amounts of "TAC" for which no "FOGRA" Profiles are available.

The E.C.I. (European Color Initiative) is a body comprising various organisations including FOGRA (the German Graphic Research Organisation) and UGRA (its Swiss counterpart). They have their specification based on the ISO standard. In conjunction with FOGRA they issue ICC Profiles, the latest of which, have become the "Industry Standard" in much of the world. These Profiles are built from "Characterization Data  Sets" which are made from an average of very many print runs, at different locations, which are as close to the ISO Standard as is practicable. These Data Sets are then smoothed out and adjusted to the EXACT standard. The latest are known as FOGRA 39 and 40. The Data Sets are available for experts such as us to make customised Profiles from. The ECI downloads are here http://www.eci.org/eci/en/060_downloads.php The latest profiles are in a file called "ECI_Offset_2007"
The default ECI profile to use for sheetfed printing on sheetfed coated stock is "ISO Coated v2 (ECI)". This is built from the FOGRA 39 Data Set. There is also a version with 300% TAC for Web Offset. Note that this has the same TVI (dot gain) as that for sheetfed. They do not recommend using older versions based on FOGRA 27 data. There are other Profiles there for "SC" paper and uncoated paper. Note that the latest "Iso" Profiles are NOT yet supplied with Adobe Photoshop CS3! On a Mac, Profiles are installed in Library/Colorsync/Profiles. There is also much other info on the FOGRA site. Note that these are suitable for International use and not just for Europe.

Euroscale. You may also come across this older  specification and Profile. This is not to the latest ISO Standard, but is still sometimes used in the U.K.

GRACOL "G7" is a USA-based "calibration methodology" to achieve Offset Printing to ISO-12647. It is not a rival to ISO! It is based on precisely calibrating the CTP device to match the actual printing press used, which is also running to ISO standard, with ISO standard ink and paper. Calibration achieves good Grey Balance and tonal gradation, especially in the vital highlight to mid-tone area. Separate "TVI" calibration curves may be required for each of CMYK. It is also becoming popular in Australia and the Far East. The G7 Data Set from which the ICC Profile was made was apparently derived from FOGRA 39. Tests done on behalf of the BPIF indicate results comparable to ECI/FOGRA methodology.  http://www.gracol.org/
You may download GRACOL and SWOP Profiles there. The latest Profile for commercial sheetfed offset use is "GRACOL2006_Coated1"

SWOP (Specification for Web Offset Publications). This has been around for a very long time, originally from the 1970's! Please be aware that most Photoshop installations default to this, even though it is now out of date and only relevant to US Web Offset, for which at one time, it was very good! Many supplied CMYK images may be in this older colour space. Information about the latest SWOP Profiles can be found on the GRACOL site. The latest SWOP Specifications (from GRACOL) are also to ISO Standard! The latest Profiles, of which there are now two for different paper types, are also there.