Hello Graeme,
The jpeg2000 file linked in the dropbox had the source image untouched
(prophoto), I had made a second jpg from it in the second mail thinking
maybe people don't respond when they need to download.
Anyhow, to be clear again here is a tiff file that has, in order:
-the source (as is, the file is 16bit ProPhoto in the first place)
-converted relative colorimetric in photoshop using the argyll profile,
then converted back to prophoto to merge into the file for visual comparison
-same as above but using an i1profiler generated ICC profile from the same
spectral data(basiccolor, profilemaker etc yielded similar if not same
result)
https://www.dropbox.com/s/1a1ubkyd8yt3sad/argyll_greenyellowdemo.tif?dl=1
I attached the strawberries for the deep red issue, visible as a
delineated/banded shadow region. The greens issue is self evident. I left
the layers intact in case you want to stack them for a quick visual
comparison.
the profile, including the data.
https://www.dropbox.com/s/z8kogv3u5vly3tp/Lamarts11880_HMRagBaryta_i1i0_DPCCMT_ArgyllR05_Photographic_Ocak2015.icc?dl=1
best,
d
On Thu, Feb 18, 2016 at 8:07 AM FreeLists Mailing List Manager <
ecartis@xxxxxxxxxxxxx> wrote:
argyllcms Digest Wed, 17 Feb 2016 Volume: 13 Issue: 021
In This Issue:
[argyllcms] Re: Yellow-ish rendering of greens out of
bounds
----------------------------------------------------------------------
Date: Wed, 17 Feb 2016 18:18:15 +1100
From: Graeme Gill <graeme@xxxxxxxxxxxxx>
Subject: [argyllcms] Re: Yellow-ish rendering of greens out of bounds
Derin Korman wrote:
Hi,
It seems that certain greens (in this case the fourth color patchstarting
from red) turn very yellow compared to other profiling solutions.
What is the source colorspace and patch values ?
Your .jpg shows the "original" 4th and 5th patches as identical RGB
values, but there is no profile tag for this file.
It's not possible to investigate without this information.
If youproblem
check the Hue values, the others more or less preserve the hue while
ditching more saturation, but the end result looks perceptually more
similar. Strangely, if I convert with perceptual colorimetric, this
disappears.
That does sound strange.
https://www.dropbox.com/s/5a4930qadrlz6ky/argyllcomparison.jpf?dl=0regardess
There is also this problem with deep reds that keeps cropping up
of device and profiling parameters
It looks more like shadows being exaggerated, but again, without the
source image and its colorspace, there's not much I can do.
Graeme Gill.
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End of argyllcms Digest V13 #21
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