ArgyllCMS help! 1000+ patch target produced very poor results

[podll]

Hi everyone. I have been trying to make watercolor reproductions on traditional cold press watercolor paper, unfortunately with very mixed results using existing profiles. Luckily I got my hands on a Colormunki to help fix this, and using the Colormunki software with only 3 targets (130 patches total) I was able to make the best matched print I've ever made.

Enter ArgyllCMS. I've read great things about it. I thought I'd take it to the next level and produce a great profile, so I generated a target with 1,050 patches, printed it out without any color management, and read it in with the following commands:

targen -v -d2 -f1050 -R -G 1050_Arches

printtarg -v2 -iCM -h -t360 -a.6 -m0.0 -M0.0 -P -p190x320 1050_Arches

chartread -v -H -B -T0.4 1050_Arches

After getting all the rows, I grabbed my local AdobeRGB1998.icc from my ColorSync folder (as I've read you're supposed to do), copied it to my working directory and used this command to generate the profile:

colprof -v -qh -S AdobeRGB1998.icc -dpp -D "Arches 300gsm Canon Pro 100" 1050_Arches

And here are the results (I apologize for picture quality) with the original on top, the Colormunki software profile on the bottom left, and Argyll's profile on the bottom right. This was printed in Photoshop with relative colormetric selected on my Canon Pro 100:



Notice the blacks are completely missing in the face and the clipping on the blue wash on the side. It is difficult to tell from this picture, but there is a green cast as well. Also, here's a 3D view from the ColorSync app comparing the Colormunki generated profile and ArgyllCMS, with the smaller ArgyllCMS profile in color and the Colormunki shown in a white outline. It's obvious that there's quite a bit less coverage in Argyll's profile. To be honest, I'm baffled that the gamut is so much smaller considering I used more than 8x the patches with Argyll:



Perhaps I've missed a valuable step in generating my profile - I sure hope so. I'm a complete novice at profiling, but I was really hoping that 1,050 patches would produce a superior profile to the 130 patch Colormunki profile. If anyone has any ideas as to what might have gone wrong here, or what else I need to do to improve this, I would greatly appreciate any help. I'm comfortable on a command line, but I will admit I simply used parameters/settings that I found from others on forums.

UPDATE: This is all sorted out. See my post on Oct. 29th.

[aaronchan]

How did you print your target?
Are you sure you were printing the targets under "absolute no color management" condition?

Aaron

[Ernst Dinkla]

There is a good ArgyllCMS mailing list where you can discuss the details of your method and the numerous settings possible in ArgyllCMS. On this site the Color Management forum may be a better place too.

Could it be that you produced an ArgyllCMS CMYK printer profile where that printer needs an RGB printer profile? It is driven as an RGB-device in color management despite having CMYKetc inks.

Measuring a 1000 patches manually with a ColorMunki may be a bit over the top anyway. Chances are that the ColorMunki's and your reproducibility are not good enough for that task.

The ColorMunki print is a bit rich in color BTW.


Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
September 2014, 650+ inkjet media white spectral plots.

[podll]

How did you print your target?
Are you sure you were printing the targets under "absolute no color management" condition?

Thanks for the reply! I'm not sure if you use a Mac or not, but the ColorSync app allows you to open a tiff file and print it as a color target. This turns off color management completely, based on what I have read.

There is a good ArgyllCMS mailing list where you can discuss the details of your method and the numerous settings possible in ArgyllCMS. On this site the Color Management forum may be a better place too.

Could it be that you produced an ArgyllCMS CMYK printer profile where that printer needs an RGB printer profile? It is driven as an RGB-device in color management despite having CMYKetc inks.

Thanks for the recommendation. I'll look into that, and posting in the Color Management forum as well. As for setting up an RGB and not CMYK profile, the targen command I used had the -d2 specification which means "Print RGB" according to the documentation here.

[aaronchan]

Thanks for the reply! I'm not sure if you use a Mac or not, but the ColorSync app allows you to open a tiff file and print it as a color target. This turns off color management completely, based on what I have read.

I highly recommend you to use Adobe Color Printer Utility to print out the target.
Mac OSX ColorSync has not been working properly since I don't know when.
You better make sure your target is printed under the No Color Management environment.

Aaron

[podll]

I'm running OSX Yosemite, so I'm not sure if I have a different version of ColorSync than others (it shows my version as 4.10). Has the "Print as color target" option been shown to not work? I'm curious as to what version you have. Here's a screenshot of what I'm seeing:



I can try Adobe Color Print Utility on my next try to see if there's any differences.

UPDATE: ColorSync DOES produce a valid color target. See my post on Oct. 29.

[podll]

Hmm... here's something I just noticed. In ColorSync, when I select "Print as color target", the colors in the little preview window (screenshot above) end up changing drastically. Is this normal? I saved the preview as a PDF on the bottom of the Print window, and here they are:

Original Argyll generated TIF target

Saved in ColorSync as printer target (PDF)

I'm going to try using Adobe's Color Print Utility to see if the same thing happens during the print.

[Mac Mahon]

I've never used Colorsync's target printing option so I can't comment on whether it's broken or not.  (I'm going to try a print-and-measure comparison).

However,

ACPU works for printing targets at least on my Epson.

But I've printed my last few targets (both for i1Profiler and Argyll) using Roy Harrington's 'Print Tool' (used to be QTR-print).  I believe he developed it initially to ensure the no-colour-management option could reliably invoked on Mac OSX.  It is really super simple, super flexible, and is quite separate from and doesn't require, QTR.  

Tim

Edit:  hmmmm.  I just looked at Print Tool's documentation (very good, incidentally).  I'm not certain that it will work with your Canon printer.  Sorry....

[podll]

Just as an update to this, I did manage to sort out my problem! I went to the Argyll CMS mailing list, and I got some help there. Here's a link for anyone interested: https://www.freelists.org/post/argyllcms/Very-poor-results-with-1000-patch-target,18

It turns out that my initial scan with my 1000+ patch target had many bad readings, most likely due to the small size of the patches. My results were as follows for colprof:

peak err = 37.499292, avg err = 0.889221, RMS = 2.756460

After making a new ~520 patch sheet with larger patches and scanning them in, I got these results upon running colprof:

Peak err = 1.633284, avg err = 0.377664, RMS = 0.441556

Much better. I'm now able to print as accurately as ever. ALSO, I can confirm that the ColorSync app DOES produce a reliable color target. There was absolutely no noticeable difference between the sheet printed with Adobe Color Print Utility and ColorSync.