Hi Roger,
I got the target from coloraid.de (http://www.targets.coloraid.de/).
Yes it came with reference file in a CD. Yes I used the reference data
when building the scanner profile.
My screen is not calibrated (and I do not have hardware to do so) so I
am guessing it would make the answer to your question useless. I check
the correctness by printing, then scanning back, and then looking
original vs replica on the same screen next to each other. I am not
expecting them to have exactly same colors, just somewhat similar is
enough for me :)
But the scanner profile was probably a success. Because I first used
the scanner profile which came with the scanner driver and got similar
yellow tint. Then I ordered the profiling target as I thought the
profile shipped with scanner was bad. So I created scanner profile
using the target, but I got similar results in my prints as with the
driver based scanner profile.
I am not convinced if the problem is the profile I created. Because I
am able to use `cctiff` to apply the profile to the image, then the
printout is somewhat reasonable (and I blame the printer for the small
inconsistency)
I guess the real question is what is the difference between:
* I apply a profile using `cctiff` to an image and print with no color
management.
* I set the profile as default profile for the printer in windows
color management then print.
Regardless of if the profile is correct or not. I would expect same
results. Isn't that a reasonable assumption? Perhaps I just don't
understand how the profiles work otherwise.
Also, since my image is in sRGB, if I set the printer profile to sRGB
in windows color management, shouldn't the result be same thing as if
no color management is used? Because I just tried it and the printouts
look different... Maybe I don't understand how windows processes these
profiles? :)
You lost me at CIE Lab value of "Paper" here is the reference data
http://www.colorreference.de/targets/R170830.zip
Anyway, thanks for the help. To be honest, this is not very important
as I just wanted to try out if I can manage to get better prints. I
think next I will try to set the printer default profile as sRGB
(instead of using no color management) and then create profile using
argyll. Then replace sRGB with the profile I created. I wonder what
the result will be :)
Thanks,
Evren
Quoting graxx@xxxxxxxxxxxx:
One question: where did the IT8.7/2 target you used came from? Something
your bought? And it came with its "Reference" data? Which you used in Argyll
to build the scanner profile? When you open up the scanned target in
Photoshop (assuming you do have it) and assign the scanner profile (or use
some other application which supports ICC color management), does the image
on screen looks remotely close to the original?
The dingy yellowish "cast" you see may come from the color-managed IT8.7/2
chart itself. Take a look at the CIE Lab value of the "Paper" in the
Reference data: if the b* value is relatively "high", like +2.00 or +3.00,
it would indicate that the paper color is indeed on the yellowish side.
When converting from the scanner profile to some other Destination, make
sure the Rendering Intent is not set to Absolute colorimetric, otherwise,
that yellowish tinge will show up everywhere and seem to "bias" your
results.
I wish you had access to a spectrophotometer. Building output profile from
spectrophotometer measurements is best. Have you heard of the Nix color
sensor? I bought one recently for about $100 and was surprised by the
relative quality of measurements. There is always eBay.... where I bought
many of my instruments over the year.
I wish I could help you more.
/ Roger
www.graxx.ca
-----Original Message-----
From: argyllcms-bounce@xxxxxxxxxxxxx <argyllcms-bounce@xxxxxxxxxxxxx> On
Behalf Of eyurtese@xxxxxx
Sent: Saturday, June 1, 2019 5:50 PM
To: argyllcms@xxxxxxxxxxxxx
Subject: [argyllcms] Epson ICM settings Windows 10 results in strange
colors?
I am having trouble with windows color management. I am trying to calibrate
my printer using Argyll CMS and the end result is slightly off...
I already asked this from dpreview so here is the link to detailed
explanation with images:
https://www.dpreview.com/forums/post/62727691
To summarize, I am using `cctiff` to apply srgb->custom printer profile
conversion.
* If I print the resulting image WITHOUT color management then the image is
as I expect it to be.
* If I upload the custom printer profile to windows color management and
select it as default. Then print pre-converted original, letting ICM do the
task itself, then the printout is different.
The weird thing is that I enabled print preview in Epson driver and the
preview image is exactly same as the `cctiff` converted image. But when it
is printed it looks different.
I think print-preview of Epson shows the final data to be sent to printer so
I do not quite understand why the end result is different when I let windows
manage ICM.
Any ideas?
Thanks,
Evren
