QTR-Quadtone RIP

Is there any special trick to using the I1 pro 2 and profiler software for measuring the C, LC, M and LM step charts that is different to black inks? When I measure using the same settings i use for the K, LK and LLK inks, i get values in the set that are too high or low making the sequence non increasing - kind of up, down and all over the place. The printed steps visually show a clear increase in density from 0 - 21, so I assume it is my incorrect use of the tool.

Here is an example for 21 steps with Cyan:

CGATS.17

ORIGINATOR "i1Profiler - X-Rite, Inc."

INSTRUMENTATION "i1Pro 2 ; Serial number 1022578"

DESCRIPTOR "cyan"

MEASUREMENT_SOURCE "MeasurementCondition=M0 Filter=no"

ILLUMINATION_NAME "D50"

OBSERVER_ANGLE "2"

FILTER "no"

WEIGHTING_FUNCTION "ILLUMINANT, D50"

WEIGHTING_FUNCTION "OBSERVER, 2 degree"

KEYWORD "DEVCALSTD"

DEVCALSTD "XRGA"

CREATED "2016-04-25T18:58:54"

NUMBER_OF_FIELDS 8

BEGIN_DATA_FORMAT

SAMPLE_ID SAMPLE_NAME XYZ_X XYZ_Y XYZ_Z LAB_L LAB_A LAB_B

END_DATA_FORMAT

NUMBER_OF_SETS 21

BEGIN_DATA

1 A1 0.78713 0.83327 0.74419 93.16 -3.21 -5.03

2 B1 0.76096 0.80747 0.71553 92.02 -3.54 -4.47

3 C1 0.75830 0.80989 0.74220 92.13 -4.54 -6.63

4 D1 0.74608 0.79952 0.74147 91.66 -5.04 -7.37

5 E1 0.71799 0.76344 0.67649 90.02 -3.78 -4.39

6 F1 0.72784 0.78326 0.73680 90.93 -5.64 -8.23

7 G1 0.71353 0.77072 0.73387 90.36 -6.17 -8.96

8 H1 0.70294 0.74666 0.66003 89.24 -3.60 -4.21

9 I1 0.70119 0.76037 0.73409 89.88 -6.73 -9.80

10 J1 0.68727 0.74848 0.73240 89.32 -7.34 -10.61

11 K1 0.69959 0.74511 0.67045 89.16 -4.00 -5.31

12 L1 0.67463 0.73758 0.73091 88.81 -7.88 -11.37

13 M1 0.66144 0.72641 0.72994 88.28 -8.50 -12.20

14 N1 0.70258 0.74667 0.66921 89.24 -3.68 -5.06

15 O1 0.64979 0.71617 0.72843 87.78 -8.98 -12.92

16 P1 0.63557 0.70364 0.72561 87.17 -9.57 -13.72

17 Q1 0.69614 0.74242 0.66991 89.04 -4.20 -5.47

18 R1 0.62781 0.69740 0.72684 86.87 -10.03 -14.35

19 S1 0.61653 0.68769 0.72589 86.39 -10.58 -15.10

20 T1 0.67741 0.73094 0.68829 88.49 -5.91 -8.10

21 U1 0.60911 0.68112 0.72384 86.06 -10.90 -15.48

END_DATA

I really couldn’t say because I’ve always built my own toner curves mathematically using beziers totally outside of the QTR curve creator.

best,
W

> On Apr 26, 2016, at 7:41 AM, mattbaily@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:
> 
> Thanks Walker, I'll check ColorPort out. Next question:
> 
> 
> On a side note. How does one create a toner_curve for each individual tone? Do I load the ink descriptor file with just that tone set with the ink limits and cross over. And have all the other inks (including black and greys) set to 0 ink limit so they do not print. 
> 
> If I printed a 4x21 random step with that, would I get it printed in just M and LM (or C and LC) - then I correct the curve for that tone from that data? Basically, wondering the mechanics of creating the toner_curve.
> 
> Thanks,
> Matt
> 
>