Hi Graeme,you know that I am sold on argyllcms, but to puzzle out the right black generation parameters sometimes drives me nuts.
I tried to generate a profile from the data set <http://color.org/FOGRA40L.txt> with a black generation comparable to to this profile: <http://www.colormanagement.org/en/isoprofile.html#SC_paper_bas> here is a screenshot of "xicclu -g -fb -ir SC_paper_bas.ICC": <http://digitalproof.info/argyll/black_gen/xicclu_-g_-fb_-ir_SC_paper_bas.png> I attended the instructions at <http://argyllcms.com/doc/Scenarios.html#PP6> and literally tried hundreds of different parameters. E.g. I create a preliminary profile with "profile -v -ql -b -no -ni -l250 F40" and tested several black generation parameters, see <http://digitalproof.info/argyll/black_gen/F40_250/>To bar the curves from gamboling around I tried to generate a bigger data set with fakeread:
targen -d4 -l300 -c SC_paper_eci.icc -A0.5 -f3000 -v3 F40fakeread fakeread -v SC_paper_eci.icc F40fakeread profile -v -ql -b -no -ni -l300 F40fakeread mv F40fakeread.icc F40fake300.icc and decided to use it with the following black generation parameters: kp 0 0.15 1 1 0.65 -l300 as the curves looked smooth an reasonable to some extent, see <http://digitalproof.info/argyll/black_gen/fakeread/xicclu_-g_-kp_0_0.15_1_1_0.65_-fif_-ir_F40fake300.png> but when I created the profile with"profile -qm -k p 0.0 0.15 1 1 .65 -l300 -L100 -S sRGB.icc -cmt -dpp F40fakeread"
I got this: <http://digitalproof.info/argyll/black_gen/fakeread/xicclu_-g_-fb_-ir_F40-fakeread.png> What am I doing wrong? Klaus