Profiling Versaworks 4

[eye4clr]

The methodology of comparing ink restrictions and ultimately density measurements in the linearization is logical but limiting. Personally I prefer to strive to get the most gamut out of a system as you can, then configure the RIP to proof for FOGRA if that's the goal. This way if you need to get a Pantone that's outside of FOGRA but inside the capability of the ink/media you're running, you'll be able to hit that. Besides, who wants to be limited to some offset spec. We can so often do so much better.

I'm curious if you're getting DeltaE from comparing output to a measured sample in something like a Pantone book or if you're comparing quality control for consistency over time. In other words, measuring something like 30% and 100% cyan today, then again tomorrow and so on.

 

[wikam]

I'm curious if you're getting DeltaE from comparing output to a measured sample in something like a Pantone book or if you're comparing quality control for consistency over time. In other words, measuring something like 30% and 100% cyan today, then again tomorrow and so on.

It`s not for quality control.
I just printing the same things regulary over time for my customers and I have to maintain the same colors. (about 400-600sqm per month).

It was easy but I changed inks two weeks ago and problems starts.
CMYK colors printed with old inks doesn`t match CMYK colors printed with new inks.
It`s normal but with good profiles I should be able to simulate "old" colors while printing them with new inks.
These colors are of course in gamut that new inks can reproduce. I check that in colormunki software and colorthink.
So in theory everything should works right?

I read "old" colors from previous prints with spectrophotometer and import that LAB palette to graphic editor. Then I printed them with new inks and new profiles. Unfortunately colors are different from the old one. (deltaE 3-8 with averange of ~5). I think it`s too high. I can see the difference with naked eye.

Profiles for old inks have been generated from 2500 patches.
Profiles for new inks are generated from 1485 patches (fogra39.txt).
Is this is the cause of my problems? Lower quality profile?

I try to make new profiles but I have only colormunki and argyll to make them. This usually works but I want to start from a scratch and make calibration and ink limits myself.
I use versaworks RIP and it don`t have support for my spectrophotometer so it`s hard.

Today I found a way (btw thanks for link to babelcolor patch tool).
I print calibration chart from versaworks and read it using argyll spotread.
Then open the file in patch tool and determine ink limit for C, M based on deltaE for chroma value and for K based on deltaE for lightness.
Now I experimenting with Y but I can`t get warm grey from CMY. Maybe I doing something wrong.

Should I print and check CMY greys after I linearize printer or just after setting single inks limit?