From version 18.1 and later MeasureColor fully supports the use of M-conditions. While some M-conditions are merely a new name for old functionality there is also a new illumination standard (M1) which is rapidly becoming important as part of the new printing standards.
Optical Brightener Agents
The development of M-conditions follows the introduction and increasing use of Optical Brightener Agents. OBA’s convert UV wavelengths in visible light making the substrate look brighter and less yellow. As a result prints may look very different viewed with or without UV wavelengths in the light source. Typically there can be a difference between colors perceived in a legacy D50 booth or in daylight.
Our traditional devices had an undefined amount of UV in the tungsten light source which caused a deviation between our human vision and the measurements we made. Prints on substrates with a lot of OBA’s can measure fine (M0) but can look blueish viewed in daylight, and the deviation could be different for every device used. M1 measurements give more control in this situation as they are made with a standardized amount of UV present in the light source.
Overview of M-conditions
|Condition||Light source class||Filter||Typical use|
|M0||Undefined / Tungsten||none||legacy spectral measurements|
|M1||D50+controlled UV||none||improved compliance with human sight on OBA rich substrates viewed under daylight or other UV emitting light sources|
|M2||Tungsten||UV-cut||improved compliance with human sight when prints are to be viewed under light sources without UV (as might be the case when printing for museums)|
|M3||Tungsten||Polarization||minimalizing ink dry-back density differences|
M-conditions and device support
|eXact Auto Scan||✓||✓||✓||✓|
|eXact XP||✓||✓||✓||eXact 2||✓||✓||✓||✓|
|NIX Spectro 2||✓||✓|
|Variable Spectro 1||✓|
* Depending on the instrument. ITX-2 can be ordered with a polarisation filter fitted which makes it M3 compatible, i1Pro1 will either always measure M0 (without filter) or always M2 (when it’s fitted with a UV-cut filter).
M-conditions are not compatible and cannot be converted
There is no way to convert between M-conditions so it’s vital that all references, jobs and measurement conditions are properly tagged with the M-condition used. When updating MeasureColor to 18.1 and later all existing references, jobs and measurement conditions will be tagged as being M0.
As a result updating to 18.1 means that all your existing Measurement conditions, References (color books) and substrate will work as expected (M0) and you can start adding other M-conditions to your setup whenever you wish.
|Job element||M-condition dependent||remark|
|Measurement condition||YES||Defines the M-condition for your measuring device|
|Reference (Color books)||YES||Existing Color books will be tagged as M0 when updating MeasureColor|
|Printing condition||NO||Substrates can be added to enable measuring for several M-conditions|
|Substrate||YES||Linked to a Reference through the PW patch|
M-conditions start with a measurement condition. For example, if you want to adopt the new printing standards you should start by adding an M1 Measurement condition in the MeasureColor system management module.
When importing references you will be asked what M-condition should be assigned. Please check with the supplier of the color library or ICC profile before selecting the correct condition. If a reference is for example M1, you can only measure M1 jobs with this Reference. Therefore it’s not possible to mix References with different M-conditions in one job.
When importing Color references the import wizard will automatically add the Reference to an existing Printing condition or create a new Printing condition if you wish.
The import wizard will also create a substrate and link that to the PW patch of the newly imported Reference.
As substrates are linked to references by their PW-patch, substrates also ‘have’ an m-condition. Only inks from references with the same m-condition can be used. If a substrate is selected that is incompatible MeasureColor will remove the inks from the job.
Printing conditions do not care about m-conditions. A Printing condition can have several substrates with their own properties. For example you can use the same Printing condition to measure ‘gloss coated’ for FOGRA 39 (M0) and FOGRA 51 (M1) measured substrates as long as both References are available.
Adding the new FOGRA Standards
The new FOGRA standards can easily be added to the existing MeasureColor setup by downloading and importing the correct ICC profiles for M1 measurement:
- Download the profiles from the ECI website: http://www.eci.org/en/downloads (look for ‘ICC profiles from ECI’)
- From the MeasureColor menu, go to the Reference manager and press the import button
- Select the download ICC profile, for this example we used PSOcoated_v3.icc (for FOGRA 51)
- Fill in the data for color names and target solid densities, set the target dot gain to ‘Calculate using imported color data’. This is important as the new FOGRA standards deviate from the legacy Target dot gain curves.
- The wizard will automatically detect D50/2. Don’t forget to manually set the M-condition to M1
- Link the new imported Color book to the existing ISO GLOSS Coated printing condition
- Create a substrate for FOGRA 51 (make a hint in the name so the operator knows which one to select when making a job)
A more detailed description of the MeasureColor Reference wizard can be found here.
Adding an M1 measurement condition for ISO 12647-2:2013
Please note that in the ISO 12647-2:2013 standard densities are informative only.
Tolerance sets are independant of M-conditions.
Nothing has changed here really. But as the M-conditions of Inks (References/color books), Measurement condition and Substrates must be the same MeasureColor will remove invalid combinations. So, before creating your first M-condition job please check:
- Do I have a Measurement condition for this M-condition
- Do I have a Reference / Color book for this M-condition
- Is a Substrate linked to that Reference’s PW patch