[argyllcms] Re: Target Black problems with ColorMunki & NEC 3090

How is the black mapped? I believe it's possible to get a black with whatever 
target chromaticities you want but you can't obtain that black with just any 
luminance level.

I may be wrong.

MfG/Roger

-----Original Message-----
From: argyllcms-bounce@xxxxxxxxxxxxx [mailto:argyllcms-bounce@xxxxxxxxxxxxx] On 
Behalf Of David Heinrich
Sent: December-09-10 11:14 PM
To: argyllcms@xxxxxxxxxxxxx
Subject: [argyllcms] Target Black problems with ColorMunki & NEC 3090

I'm using the ColorMunk Photo to try to calibrate a NEC LCD3090WQXi-BK LCD 
(http://snipurl.com/nec3090). After running

sudo ./dispcal -yl -P 0.5,0.5,2 -a 58.7 -B 100 -t 5000 -T 5000 -v -o TargetA

I do the following, and get the results below (I omit the menu screen, and just 
show results). The target black is way off (see results during calibration, and 
at check all step). When I adjust the offsets on my LCD, it seems to have 
little effect on the DE for adjusting the black point. My monitor also has more 
than just RGB offset controls; for the offset controls, it has red, yellow, 
green, cyan, blue, and magenta controls.

Because of the large DE, I did not proceed to calibration.

Any suggestions?

**Black level adjustment**
Adjust CRT brightness to get target level. Press space when done.
   Target 1.54
/ Current 1.55  -

**White point adjustment**
Doing some initial measurements
Red   = XYZ 112.11  51.19   1.29
Green = XYZ  32.47 112.45  16.99
Blue  = XYZ  24.66   9.07 130.81
White = XYZ 169.22 172.74 149.94

Adjust R,G & B gain to get target x,y. Press space when done.
   Target Br 172.74, x 0.3451 , y 0.3516 \ Current Br 171.06, x 0.3449+, y 
0.3515+  DE  0.1  R=  G=  B=

**White Level Adjustment**
White = XYZ 167.80 171.01 147.73

Adjust CRT Contrast or LCD Brightness to desired level. Press space when done.
  Initial 171.01
\ Current 171.02

**Black point adjustment**
Black = XYZ   0.00   0.00   0.00
Grey  = XYZ  36.01  36.78  31.72
White = XYZ 168.29 171.51 148.11

Adjust R,G & B offsets to get target x,y. Press space when done.
   Target Br 1.72, x 0.3451 , y 0.3516
\ Current Br 1.26, x 0.3725-, y 0.3873-  DE 14.5  R-  G-  B++

**Check all**
Black = XYZ   0.00   0.00   0.00
Grey  = XYZ  35.71  36.50  31.48
White = XYZ 167.52 170.96 148.22
1%    = XYZ   1.22   1.27   0.80

  Current Brightness = 170.96
  Target 50% Level  = 32.39, Current = 36.50, error =  2.4%
  Target Near Black =  1.71, Current =  1.27, error = -0.3%
  Target white = x 0.3451, y 0.3516, Current = x 0.3442, y 0.3513, error =  
0.53 DE
  Target black = x 0.3451, y 0.3516, Current = x 0.3718, y 0.3866, error = 
14.25 DE


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