Digital BW, The Print

Roy, Steve,

Thanks both of you for your help. I agree this shoud go more 
practical. So my system :

Windows XP
Epson 1280
PiezoBW ICC CIS (K, Dark grey, 2 same grey, 2 same light grey, the 
tubing and correspondances KCMY/LC/LM with the Piezo inks have of 
course been re-checked)
DTP 20 X-rite Spectro
Colorshop X for color/gamut/profile/measures viewing
Paper : EEM 

The curve is :

PRINTER=Quad1290
CURVE_NAME=EEM2
GRAPH_CURVE=YES
N_OF_INKS=6
DEFAULT_INK_LIMIT=65
BOOST_K=75
LIMIT_K=
LIMIT_C=
LIMIT_M=50
LIMIT_Y=50
LIMIT_LC=
LIMIT_LM=
N_OF_GRAY_PARTS=4
GRAY_INK_1=K
GRAY_VAL_1=100
GRAY_INK_2=C
GRAY_VAL_2=39
GRAY_INK_3=M
GRAY_VAL_3=12
GRAY_INK_4=Y
GRAY_VAL_4=5
GRAY_HIGHLIGHT=4
GRAY_SHADOW=8
GRAY_OVERLAP=5
GRAY_GAMMA=1
GRAY_CURVE=
N_OF_TONER_PARTS=0
TONER_HIGHLIGHT=10
TONER_SHADOW=10
TONER_GAMMA=1
TONER_CURVE=
N_OF_TONER_2_PARTS=0
TONER_2_HIGHLIGHT=10
TONER_2_SHADOW=10
TONER_2_GAMMA=1
TONER_2_CURVE=
N_OF_UNUSED=0
COPY_CURVE_LC=M
COPY_CURVE_LM=Y
LINEARIZE="96,37 81,17 70,98 62,61 54,44 48,72 45,2 41,69 38,03 34,46 
32,23 30,35 29,03 27,75 25,28 22,65 20,87 19,72 18,61 18,08 17,75 "

L* measures once linearised :

L A B
96,45 -0,20 -1,20
92,90 -0,06 0,03
89,24 0,12 1,26
85,27 0,31 2,21
81,34 0,56 3,00
77,40 0,68 3,63
73,61 0,76 4,15
70,04 0,84 4,32
66,63 1,01 4,34
62,30 1,13 4,52
58,03 1,25 4,48
53,54 1,42 4,28
50,04 1,39 4,27
45,97 1,44 3,81
41,94 1,35 3,41
37,92 1,29 3,10
34,08 1,02 2,91
30,44 0,86 2,10
25,85 0,78 1,77
21,73 0,85 1,67
17,70 0,73 1,24

PM5 file I feed Create-ICC with :

LGOROWLENGTH 1
CREATED "7/21/2003" # Time: 12:57
INSTRUMENTATION "eye-one"
MEASUREMENT_SOURCE ""Illumination=D50 ObserverAngle=2°
WhiteBase=Absolute Filter=No""
KEYWORD "SampleID"
KEYWORD "SAMPLE_NAME"
NUMBER_OF_FIELDS 9
BEGIN_DATA_FORMAT
SampleID SAMPLE_NAME GRAY XYZ_X XYZ_Y XYZ_Z
LAB_L LAB_A LAB_B
END_DATA_FORMAT
NUMBER_OF_SETS 21
BEGIN_DATA
1 A1 0.00 90.30 93.00 83.24 96,45 -0,20 -1,20
2 B1 5.00 81.48 83.75 73.66 92,90 -0,06 0,03
3 C1 10.00 72.64 74.52 64.14 89,24 0,12 1,26
4 D1 15.00 64.02 65.53 55.03 85,27 0,31 2,21
5 E1 20.00 56.26 57.46 47.10 81,34 0,56 3,00
6 F1 25.00 50.08 51.05 41.01 77,40 0,68 3,63
7 G1 30.00 43.86 44.60 34.99 73,61 0,76 4,15
8 H1 35.00 37.74 38.29 29.29 70,04 0,84 4,32
9 I1 40.00 32.45 32.85 24.73 66,63 1,01 4,34
10 J1 45.00 27.61 27.90 20.62 62,30 1,13 4,52
11 K1 50.00 23.84 24.05 17.57 58,03 1,25 4,48
12 L1 55.00 20.16 20.31 14.71 53,54 1,42 4,28
13 M1 60.00 16.91 17.04 12.35 50,04 1,39 4,27
14 N1 65.00 13.62 13.72 9.98 45,97 1,44 3,81
15 O1 70.00 11.01 11.10 8.10 41,94 1,35 3,41
16 P1 75.00 8.96 9.04 6.59 37,92 1,29 3,10
17 Q1 80.00 7.10 7.16 5.22 34,08 1,02 2,91
18 R1 85.00 5.56 5.61 4.11 30,44 0,86 2,10
19 S1 90.00 4.32 4.36 3.18 25,85 0,78 1,77
20 T1 95.00 2.92 2.95 2.21 21,73 0,85 1,67
21 U1 100.00 2.04 2.08 1.56 17,70 0,73 1,24
END_DATA

As you can see only the Lab (not the xyz, just a bit lazy to do the 
copy/paste manipulation also for xyz but it does not seem to be 
necessary)have been modified from a file I found (BTW on one of the 
groups).

Now L* measures :

- G2,2 is the QTR stepwedge opened in PS converted to grey working 
space gamma2,2 (all values read from 0-100 in 5 even steps)and 
printed on EEM.
- G2,2 is QTR stepwedge opened in PS converted to grey working space 
gamma2,2 and converted again with the QTR ICC created (values from 0-
100 is various steps after the QTR conversion as expected)and printed 
on EEM. 

G 2,2	G 2,2_Profil

96,16	96,31
92,75	92,82
88,97	87,89
84,98	83,7
81,03	79,67
76,85	75,25
72,72	70,42
69,22	66,39
65,85	62,03
61,83	57,92
57,86	54,21
54,04	49,45
50,62	46,73
46,93	41,67
42,84	36,07
38,59	30,65
34,4	26,86
30,44	23,35
25,46	19,83
21,31	18,43
17,93	17,5

My problem is :
1. I expected the compression resulting of the conversion should be 
in the form of a "perfect" curve but if you draw the G2.2profiled L* 
curve (excel)you will see "bumpings" (I guess this is the way you say 
it in English). G2,2 is a straight line, while G2,2_Profil is neither 
a straight line (fine) nor a perfect curve in a kind of gamma shape 
one.
2. Why the Generic Matte Profile and the QTR ICC created one don't 
have the kTRC curve in the same part of the 45° line (GMprofile 
above, mine below?).In IMHO both should be in the upper part 
(lighter) because if Lblack is no pure black the all values should be 
lighten "perceptual". Besides GMprofile kTRC is a perfect curve again 
in a fine gamma shape look, while the one I get is an bumped bowl 
shape (what my 3-years-old daughter would draw as a smile !!!). It 
doesn't matter really nut this is where I feel it demonstrate a 
problem.
3. I get significant blockages in the 90-100 once the profile is 
applied so that I did not even bother running the Piezo test for the 
lightest 10-5% and darkest 90-95%.

At the time I'm writting it I'm just getting a bad doubt : should the 
PM5 file first be feeding the "QTR-Linearize-data" and the after get 
the "whatever-out.txt" dropped to "QTR-create-ICC" ? 

I'm FOR SURE doing something wrong but can't identify... 

I can e-mail my profile or whatever is needed if necessary.
Sorry for my wording, it's not too easy to express these things.
Thanks again.

Olivier