Datacolor User to User Support Group.

--- In colorvision_group@yahoogroups.com, David Miller <dm2363@...> 
wrote:
>
>> 
> No, that should work for QTR-create-ICC. How many steps of gray are
> you measuring, though? All of the PFP code was done and tested 
with the
> 21 step QTR targets; if you're trying it with something else (I 
thought
> the other options was 100 step, or so?) then maybe something needs 
to be
> changed in PFP for that.
> 
> Same comment with the first set of measurements for QTR 
linearization.
> 
> The overall process (I haven't done this in months, but I'm 
working from
> memory):
> 
> - Set up your ink limits, do all the rest of that initial QTR 
setup. Then
> build a QTR "profile" (which are actually curves for the GIMP rip, 
it's not
> an ICC profile) and print the 21 step gray through that.
> 
> - Measure it with the PFP 2.0 Measure tool and use the QTR 
override controls
> to get the proper text formatting for the "LINEARIZE=" line that 
you'll paste
> at the bottom of the QTR file. This should give you an ascending 
series of
> density values. NOTE: the first few times I tried this, I had 
problems getting
> QTR to build a profile from the resulting file, even though 
everything "should"
> have been correct. Eventually I dug into old entries in the 
DigitalBlackAndWhite
> list on Yahoo and found references to similar problems. It had to 
do with the
> ink limits; once I changed those some more, rebuilt the original 
QTR profile
> and reprinted/remeasured the 21 steps, it suddenly worked as it 
was supposed
> to.
> 
> - Now you have a QTR profile that's got linearization. (based on 
your ink
> limit setups, and whatever other QTR keywords you used, and the 
linearization
> coming from the PFP measurements of density on the 21 step scale). 
You now
> use THAT profile to reprint the 21 steps; then measure those again 
with
> PFP 2.0, and this time, export the values into CreateICC format 
using the
> override controls in the Measure dialog. This makes a text file in 
the format
> that CreateICC expects (which is actually a Gretag Macbeth 
format...:-)
> CreateICC -should- be able to swallow that file and produce the 
right results.
> 
> Try this with 21 steps, first, and see if you can get through the 
entire
> workflow. Can you send me a copy of the file you're creating for 
CreateICC
> so that I can have a look? Just email it to davem@...
> 
> 
> Best regards,
> 
> -- 
> David Miller
> Senior Software Developer, Digital Color Solutions
> ColorVision
>

Hi David. I've measured the 51 gray target,I'll try again with the 
21,as you suggested.If the case I'll send the new file (I've deleted 
the old one 51gray).

Thank you very much

Luca