Thanks a lot Alan - working on Excel tonight!
How do you measure Dmax?
I have the i1Pro2 and full suite of i1Profiler, ArgyllCMS 2.3 of course, X-Rite
Color Port and QTR
Paul
On Wednesday, March 23, 2022, 07:04:27 AM CDT, Alan Goldhammer
<dmarc-noreply@xxxxxxxxxxxxx> wrote:
Paul,
Here are some comments.
For ‘targen’ I use the default number of white and black patches. I use ‘-g51’
for my B/W step gradient. I’ve tried this against a 21 step gradient and
observed there is a little bit better separation in monochrome printing. Your
Dmax readings are too high in relation to anything that I have measured (the
highest Dmax I have ever seen is 2.4 with Museo Silver Rag). I don’t know why
your value is that high.
You can create a file to import into Excel using ‘profcheck’ Here is an
example of one I used for a Canson paper I profiled a while back, profcheck
-v2 -k -w -x -m Canson_Rag_Photo.ti3 Canson_Rag_Photographique.icm >
final_logfile.log You then open ‘final_logfile.log’ in Excel. You can run
‘profcheck’ using this destination file ‘final_logfile.xls’ which is a native
Excel file extension but then you get a pop up window that says the file format
and extension don’t match which is not correct, you can click on yes to open it
anyway. When the file opens up you get a dialogue box that says your data file
is ‘delimited’ which is right so you click next and get a dialogue box that
will help better display the data. You must check the ‘space’ box to get your
data to display in columns. Click finish and you have the data set that can
be sorted. If you scroll down to the bottom you get the error read outs for
the data set: max error, avg error and RMS error.
I remember reading a while back that Red River profiles are prepared using M3
readings done by Chromix. There was a pretty contentious debate about whether
the use of M3 readings. Here is the link to the discussion:
https://forum.luminous-landscape.com/index.php?topic=118349.40
Alan
From: argyllcms-bounce@xxxxxxxxxxxxx <argyllcms-bounce@xxxxxxxxxxxxx> On Behalf
Of Paul Hornung
Sent: Tuesday, March 22, 2022 10:27 PM
To: argyllcms@xxxxxxxxxxxxx
Subject: [argyllcms] Re: colormunki vs other Hardware
Graeme/Alan and others,
Thanks for Average tool Graeme.
Alan - yes on needing a good test image to judge characteristics or output.
Using the 40mb tiff test image that has the 4 children and the
strawberrys/aspens/lava, etc. this is the refinement I have been able to
achieve and subsequent question:
1) Printing on a new Pro-2100 with OEM ink using Red River Polar Satin (some
OBA) paper and the stock Red River profile (Gold standard as I have read) with
the RR media setting for that paper...
The test image prints exceptionally well meeting essentially all the subjective
criteria for the image. Transitions all good, color casts appropriate,
separation in colors, neutral linearization, strawberries look very edible, not
dark at all etc. This is all just straight out of the box printing so far with
everything OEM except for the paper being Red River.
Here is my question:
The image has a black square for spot reading with my i1Pro2.
Dmax with the above test image is measured at 2.76 and on the grey ramp at the
bottom that has the grey squares going from 2 to 24 you can barely see
separation at number 4 and for sure at 6 or the second or third grey square and
they get progressively lighter and contrasty moving to the right. This profile
also is basically flawless when viewed in i1Profiler - a perfect Star Destroyer
to use Star Wars analogy - literally perfectly smooth.
2) The second test print is everything the same as above except the profile
used was made with ArgyllCMS 2.3 using 500 patches on same paper - dried 24
hours - read once - preconditioned with Adobe1998.icm and -g64 - printed with
Adobe utility for no CM - here is the workflow
targen -v -d2 -c "RR Arctic Polar Satin Can PRO 2 4 Series.icc" -G -e8 -B8 -g64
-f500 Polar
printtarg -v -ii1 -a0.92 -R1 -T300 -p Letter Polar
chartread -v -H -T0.4 Polar
colprof -v -qh -r1.0 -S AdobeRGB1998.icc -cmt -dpp -D"RR Polar Satin" Polar
a basic nothing fancy ArgyllCMS profile and printed with RC and BPC with the
Photoshop Professional Print layout with same media setting as first image. So
only thing that changed was the selected profile.
Visually in i1Profiler this Argyll profile was basically the same "size" as the
RR profile but had bumps/waves here and there, i.e. looking down the sides of
the 'Star Destroyer' there are waves but nothing too significant but obviously
not as smooth as the RR profile.
Using this profile the same test image with everything else being the same as
far as print settings did print very nicely at the same 8.5x11 - average viewer
would not detect a difference even side-by side.
However, Spotread of the black test sqaure has a Dmax of 4.75. The grey
squares don't start showing separation until 10 and upon better comparison the
second test print shows some colors a bit more saturated due possibly to the
black point issue but no color casts and meets the subjective criteria for the
test image and is a objectively good print.
Finally, 3) Using the Average tool that Graeme told me about the other day the
same patch print is reread and yields a .ti3 file of the same size as the first
on but the measurement numbers are indeed different. The first read and the
second read are averaged and a new profile created using the same method as
above but with the averaged .ti3. This profile looks visually almost exactly
like the Red River profile except a bit larger actually but nearly as perfectly
smooth - thus significantly smoother than the single read profile and bigger.
This alone was a GREAT outcome and thank you again Graeme/Alan.
I did not want to believe that rereading would make a difference but if clearly
does.
The test image printed with same settings as the first two except with the
Averaged profile. Result is also a very nice print and essentially the same as
the Red River store profile print but now Dmax is 3.4 v.s the 2.76 with RR and
on the grey ramp the first discernable square is 6 and the remaining get
lighter but not as fast as the RR profile. So the averaged profile halved the
distance between the first two Dmax's if that makes sense.
Also on all three test prints the white ramp next to the black ramp - the white
squares get darker sooner with the two ArgyllCMS prints than the RR profile
print when looking from the pure white 254 square going to the right down to
243.
So here is the question,
How can I get Dmax and black and white ramps to be more like the Red River
profile?
Increase -g? Do the grey scale linearization with QTR trick? Not
pre-condition using the RR profile?
Also, Alan is the Excel spreadsheet to import the.ti3 data into availble on the
website? My Excel is limited but see the great benefit of being able to
recognize outliers even after being averaged and Excel would be a great tool
for that.
Thanks for any thoughts y'all,
Paul
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On Thursday, March 17, 2022, 06:44:02 PM CDT, Graeme Gill
<graeme@xxxxxxxxxxxxx> wrote:
Paul Hornung wrote:
And this is where I have a question myself as to workflow .... how does one
average target reads?
