usually the problem with Gutenprint is linearisstion
On Saturday, March 11, 2017, C. H. <c.hrabia@xxxxxxxxx> wrote:
Hi everyone,
my goal with printer calibration in Linux is to get similar photo printing
quality as my printer provides used with Windows. The problem is that the
printer does toally fine in Windows, but in Linux with the available
Gutenprint driver I have issues with the color.
In consequence I came up with the following process:
1. Creating a target in Linux
1. targen -d2 -g30 -f376 target_patches
2. printtarg -t300 -p4x6 -r -s -iss target_patches
2. After that I printed the resulting two tiffs with default settings
in windows
3. I scanned the resulting prints with my uncalibrated scanner
1. My idea here ist that I do not need to have a calibrated scanner
(avoids to buy a professional target) as I just want to compare the
results from my printer in linux and windows. Please correct me if I am
wrong.
4. Next step was reading out the values of my reference windows print
1. scanin -v -o scanner_0001.tiff target_patches_01.cht
2. # creates scanner_0001.val
3. scanin -v -o scanner_0002.tiff target_patches_02.cht
4. # creates scanner_0002.val
5. In order to create a reference file based on the read in values I
came up with the following
1. I opened both .val files in Libre Office Calc as csv and sorted
the columns in ascending order
2. Next I converted the values in the rgb columns to the same
format as in the initially created target_patches.ti2 (divide by 255 and
multipied with 100)
3. Than I made a copy of target_patches.ti2 and opened it as well
with Libre Office Calc. Here I replaced the RGB values with the
calculated
values from above and saved everything to ref.csv
4. Does this make sense?
6. Then I printed the target_patches from above in linux and scanned
them as well
1. scanin -v linux_print_0001.tiff target_patches_01.cht ref.csv
2. scanin -v linux_print_0002.tiff target_patches_02.cht ref.csv
3. I combined both resulting linux_print_0001.ti3 and
linux_print_0002.ti3 manually with a texteditor into a single file (I
don't
know if there would be a better solution?!)
7. Finally, I used "colprof -v -qm -ax -u scanner" to create a
profile.
However, the resulting profile did not solve my color problem (mostly
problem with the grey ramp). Does my approach make sense? Do you have any
recommendations or suggestions?
Thanks in advance,
Chris
