Yves,
M3 refers to the use of a polarizing filter during measurements.
Your ColorMunki does not have a selectable polarizing filter, does it?
/ Roger
From: argyllcms-bounce@xxxxxxxxxxxxx <argyllcms-bounce@xxxxxxxxxxxxx> On Behalf
Of Yves Gauvreau
Sent: December 15, 2019 5:40 PM
To: argyllcms@xxxxxxxxxxxxx
Subject: [argyllcms] Re: Can we control the shadows (was black point
compensation)
Roger,
I found something interesting here
(https://luminous-landscape.com/red-river-palo-duro-softgloss-palo-duro-etching-san-gabriel-baryta-paper-review/).
The M3 filter is both the culprit and the savior here as it is explained in
the article.
From this article whatever I get without using this M3 filter won't be
satisfactory. Because it's very likely neither of us will have one these
spectro with an M3 anytime soon, we need to trust that the M3 profile will give
us better prints for normal real world images then we could get from a regular
non M3 profile.
It answer indirectly my question as well, the target patches we use, the
measurement we make of them, the degree of smoothness we use, etc. all of this
contribute to the final results. In the article the author speaks of deep
shadow detail
"We still need to look at the question of deep shadow detail using the 30
Neutrals test. Recall, this test is looking for the extent of tonal separation
in the deep quarter-tones from L*1 to L*30, which is graphically indicated by
the closeness of fit between the red line for the measured values relative to
the linear black line, which is a 45 degree trajectory with a slope of 1.0
meaning a 1L* rise of output [from the printer] relative to a 1L* rise of input
[from the so-constructed test image file])."
It's good to know, we may have a test to evaluate deep shadows, but what do we
do the results? I think the terminology I was looking for is "tonal separation"
, I thought using black point compensation would improve this tonal separation.
Yves
On 12/15/2019 4:30 PM, graxx@xxxxxxxxxxxx <mailto:graxx@xxxxxxxxxxxx> wrote:
Yves,
I took a look at your profile " RR_PaloDuroSGR_PRO1000.icm" in Photoshop.
I created a new RGB document with Black background, and assigned your
profile to the document. In Color Settings, under Conversion Options, I
selected Absolute Colorimetric.
Then I placed the ColorPicker on the background and got Lab = 0,0,0.
That does not make sense? No device in the world can give you that
measurement value, it's impossible.
That is why I strongly suggest that you obtain the CIE Lab value for
"Black".
Know what you are dealing with before you conclude anything about the
relationship between the monitor appearance and the print appearance.
Can you send me the ti3 file?
/ Roger
-----Original Message-----
From: argyllcms-bounce@xxxxxxxxxxxxx <mailto:argyllcms-bounce@xxxxxxxxxxxxx>
<mailto:argyllcms-bounce@xxxxxxxxxxxxx> <argyllcms-bounce@xxxxxxxxxxxxx> On
Behalf Of Yves Gauvreau
Sent: December 15, 2019 3:32 PM
To: argyllcms@xxxxxxxxxxxxx <mailto:argyllcms@xxxxxxxxxxxxx>
Subject: [argyllcms] Re: Can we control the shadows (was black point
compensation)
Roger,
I can of course print and measure whatever patches out there but how will
this help in creating a better profile especially to exploit as much as
possible the finest of details in the deep shadows?
Maybe it's written there in plain site but I just don't understand the
meaning, it wouldn't be the first time.
Thanks,
Yves
On 12/15/2019 10:39 AM, graxx@xxxxxxxxxxxx <mailto:graxx@xxxxxxxxxxxx> wrote:
Yves,
Do yourself a favor to "analyze" the paper measurements.
Look at the ti3 file "numbers".
Or, at least, print a grayscale that goes from 255,255,255 to 0,0,0 in
10 increments, let's say, on your paper and measure each printed
patch, to see what kind of Lightness value (L*) you get? A good,
coated paper will give you L* < 15. Newsprint paper is usually no lower
than 28 to 30.
What value are you getting on your print for the darkest black?
Yes I can do all of this but can I use the measure to improve the profile so
these deep shadows look much more like what I see on screen?
/ Roger
-----Original Message-----
From: argyllcms-bounce@xxxxxxxxxxxxx <mailto:argyllcms-bounce@xxxxxxxxxxxxx>
<mailto:argyllcms-bounce@xxxxxxxxxxxxx> <argyllcms-bounce@xxxxxxxxxxxxx>
On Behalf Of Yves Gauvreau
Sent: December 15, 2019 7:38 AM
To: argyllcms@xxxxxxxxxxxxx <mailto:argyllcms@xxxxxxxxxxxxx>
Subject: [argyllcms] Can we control the shadows (was black point
compensation)
Roger,
I'm sure the way I said this is likely not the best way.
I understand there is a physical limit to how "black" we can get from
this or that paper, inks and printer combination. The same goes for
the whitest value we can get, these are physicals limitations.
If you compare the 2 region on the bottom of this image as seen on
screen with a print of this same image on most paper, at least all the
ones I used with very few exception.
(http://www.jirvana.com/printer_tests/PrinterEvaluationImage_V002.zip)
The highlights squares of value 254 to 243 on a white (255) background
always print such that they appear very similar to what's on screen.
With my old eyes, except for the patch 254 I can always see from 253
to
243 easily just as on screen.
On the other side, the black patches on a black (0) background what I
can see on the print is very dependent on the paper I used. On a photo
rag satin paper by Hahnemuehle which uses my printer matte black ink,
I get basically what I see on my screen, again with my old eyes I can
see down to patch number 6. With some other paper I can see a
difference only from patch number 18.
My question, is there a way to create a profile that would better "render"
the deep shadows of this image so most if not all papers look more
like what's on my screen. Just in case it helps this especially for
non glossy paper for which I don't care much even if they are in
general better at this deep shadow stuff.
Is it a question of increasing the number of patches in the deep shadows?
Is it a question of the quality of the measures?
Any suggestion?
Thanks,
Yves
On 12/13/2019 6:20 PM, graxx@xxxxxxxxxxxx <mailto:graxx@xxxxxxxxxxxx> wrote:
Doesn't it "depend" on the paper, Yves?
Some papers "absorb" more than others?
And even though the printer adds more ink, it is only "absorbed"?
And you don't extra "Extra L*" for it? (L* does not go down?)
/ Roger
-----Original Message-----
From: argyllcms-bounce@xxxxxxxxxxxxx <mailto:argyllcms-bounce@xxxxxxxxxxxxx>
<mailto:argyllcms-bounce@xxxxxxxxxxxxx> <argyllcms-bounce@xxxxxxxxxxxxx>
On Behalf Of Yves Gauvreau
Sent: December 13, 2019 6:17 PM
To: argyllcms@xxxxxxxxxxxxx <mailto:argyllcms@xxxxxxxxxxxxx>
Subject: [argyllcms] black point compensation
Hi,
I'm trying to choose some fine art papers. I always print de same
image I got from here
(http://www.jirvana.com/printer_tests/PrinterEvaluationImage_V002.zip
) so I can compare apple with apple hopefully.
Many fine art papers have a black point of around L* 16 but with some
I can see many squares in the bottom left, with one I have, I can see
down to square 6 while other with a similar black point value if not
identical, I can only see down to square 16-18.
It's all over the place basically, so my question is, can we can do
something about that? On most if not all my prints with this image I
can see up to square 253 almost all the time. Would be nice to have
similar on the dark side.
Thanks,
Yves
