Print Quality Screening
At the “Print Linearization Chart” step please choose both FM (Frequency Modulated or Stochastic) and ED (Error Diffusion) screening as per screenshot below from the Ink Setting menu and evaluate both resulting outputs for smoothness of dot distribution and sharpness of text.
You can go back and press the unlock button to change the screening and then print again. You will find that different printers using differing head technologies will provide smoother more accurate output with either one or the other screening options.
The above should be used for both ICC and MX calibration processes.
Advanced Ink Cut adjustment in MX colour engine to maximise printer gamut
For adjustments below please use the up and down arrow keys on the keyboard.
- For Cyan look at the Chroma C value and b+ value to see if there is any more increase after the software clips automatically due to duplication or bunch-up. Sometimes it is possible to get more Chroma and b+ value by stepping up from the pre-set %.
- For Magenta look at the Chroma C value and a+ value to see if there is any more increase after the software clips automatically due to duplication or bunch-up. Sometimes it is possible to get more Chroma and a+ value by stepping up from the pre-set %.
- For Yellow look at the Chroma C value and b- value to see if there is any more increase after the software clips automatically due to duplication or bunch-up. Sometimes it is possible to get more Chroma and b- value by stepping up from the pre-set %.
- For Black look at the L value only to see if there is any more increase after the software clips automatically due to duplication or bunch-up. Sometimes it is possible to get more darkness/d max by stepping up from the pre-set % (please note that ISO Coated L is 16 and that if you are looking at .1 or .2 increases with higher ink percentages then it is most probably not worth the extra ink as you will see no visible difference) This step will not increase gamut obviously but may allow darker shadows.
Once you have established the maximum gamut for the CMY inks and darkness or for K then increase ALL these ink cuts (if possible) by a further 3% (this step allows for the gamut reduction that happens later in the MX generation for iterative re-calibration purposes).
The following screenshots where using the arrow keys on the keyboard to increase the percentage Cyan value past the pre-set clip and where it gains more Chroma and B value but then starts to go down (click on further as it may go higher again but you will have to decide if the increase is worth the extra ink used).
We choose screenshot 3 @ 79% and then apply 3% more to counter the gamut reduction for recalibration later in the profiling process (you don’t see this as its done in background). Please use the same process with Magenta looking at Chroma and A value and Yellow looking at Chroma and B value.
In the next additional screenshots below we show you the light ink to dark ink transition presets that start with 3 – default (Balanced).
Please analyse the gradations on the Ink Limit test chart after setting to Medium and Ecosave as the light inks do not normally add colour gamut but just smoothness in highlight to quarter tones and should be used sparingly to save ink. If you can see no discernible additional graininess or steps in those areas of the linearization ramps or gradient balls for the light ink supported primaries then use the lowest of the presets possible.
The last screenshots show there is more d-Max to be had on the k channel than the pre-set by going up with the arrows. This of course, doesn’t add gamut but allows for deeper shadow areas which are a key to flatter UV inks.
Evaluating the Ink Limit chart
The aim here is to get the maximum gamut but not at the expense of print artefacts such as UV gloss banding (stripe effect due to over inking), Latex non-curing (oily effect on patches not dry), Solvent tackiness (where the patches are still too sticky by the time the media reaches take-up) and any other over inking indications such coalescence, mottling, pooling etc. Please try to choose a patch that doesn’t exhibit any of these whilst making sure that you are way past the maximum Red, Green and Blue values and ideally deep into the shadow areas for the coloured ramps.
Once you see relatively no colour towards max ink then there is no point in going further as no more shadow darkness will be produced.