Re: Re:Color checker and color balance{New questions}
Re: Re:Color checker and color balance{New questions}
- Subject: Re: Re:Color checker and color balance{New questions}
- From: email@hidden
- Date: Sat, 25 Nov 2000 11:39:45 EST
In a message dated 11/25/00 7:24:20 AM, email@hidden writes:
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I am trying to put this all into context for color balancing digital photos
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and art, to be "printed" via A] a traditional EP2 lab{RBG} and B} offset
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lithography {CMYK in brochures,catalogues,etc.}. At this point I am not
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relying on the monitor to see color{ I have a spyder package on order}
Thats a start, but you won't have the puzzle solved unless you get one of the
bundles that include printer calibration software as well... you can get
ProfilerRGB, ProfilerCMYK, or ProfilerPro (depending on your needs) along
with your Spyder as a bundle.
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but
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rather the RBG/CMYK values of the GretagColor Checker.
Again, this is useful but no replacement for profiling software...
I will expand my
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questions for a moment based on the above:
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1.I should assume then, that I should be handling the images in the color
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spaces relative to each of these output suppliers.
No, you should be handling them in your RGB workingspace, and converting as
the last step in preparing for a specific output device.
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...if so, in capturing the image, should the initial capture{digital} be
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handled and saved in these respective space..and/.or is it of any
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consequence to capture and save the file in another space and allow
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photoshop to convert it?
There really is no "capture" space, we use profiles to attempt to accurately
open files to LAB or a Photoshop workingspace, but don't let those source
profiles fool you into thinking he source devices have a defined gamut in the
sense of a monitor or printer; and don't try to use your source device's
profile to define a workingspace, just use it to convert to a standard
Photoshop workingspace.
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2. Although I have not tried this, would it be of benefit to capture &
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color
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balance the images in LAB mode...and then convert to there respective
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spaces?
If you are a LinoColor or NewColor user, that is what you will be required to
do, if you are using Photoshop as your color management operator, then a
PhotoShop RGB working space makes more sense.
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3.I understand that any defined SPACE represents different gamut of color{I
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think this is a correct statement} but why doesn't the SAME color{ie. from
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this chart} have any absoulte value{color temp?,etc} that represents itself
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in all platforms?
It does, in an absolute system like LAB, but LAB is not most people's choice
of an easy and intuitive space to work in.It also has a controlled value in
an absolute *related* system like a Photoshop RGB space. Any RGB number with
a workingspace designation, will appear and function similarly on all
systems, gamut limits aside...
How can OUT of Gamut colors be "defined" if their readings
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are different in various spaces?
All colors have different numbers in different spaces (in gamut or out), and
are out of gamut based on the space or device they are being compared to...
What is out of gamut for SWOP may well fit nicely on a LightJet.
Other to say that this given space cannot
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reproduce this color...it still must be defined in some absolute, meaningful
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cross space manner.? I am still having a hard time understanding how a
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grey
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value of 30/30/30 {for instance} will or even should be different depending
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on the working space.
In a Gamma 2.2 space it will be a lighter or darker gray than in a gamma 1.8
space, by definition. Just as a green of 0,255,0 will be brighter on coated
paper than on newsprint; each paper defines a different space or gamut with
the same inks and press, thus the higher gamut coated paper space will offer
a brighter green for the same ink formula. In most device spaces, 30,30,30
will not even be a neutral gray, though in Photoshop workingspaces, it is
neutral by definition.
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4. In attempting to color balance these shots, what would the consequence
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be
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of manipulating/retoutching the shots prior to conversion to the final
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working soace?
Color balance and manipulate (and archive!) in a Photoshop RGB workingspace,
where the monitor will do a reasonaable job displaying your image and
changes. Only when you are ready for final output should you convert to a
specific device space for printing.
I have been converting the CMYK shaot BEFORE i do any
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manipulation
Well thats the wrong order, but there are still those who will insist in
doing it that way... once you have done the majority of your corrections, it
doesn't hurt to look at the seperations in CMYK and see if you want to make
any final plate changes there... its just not the preferred place (any
longer) to be doing your major editing, as its on the wrong side of the black
generation and ink limit calculations.
C. David Tobie
Design Cooperative
email@hidden