Re: ProfileMaker Tone Compression
Re: ProfileMaker Tone Compression
- Subject: Re: ProfileMaker Tone Compression
- From: Henrik Holmegaard <email@hidden>
- Date: Wed, 1 Nov 2000 19:33:47 +0100
Roger Breton <email@hidden> wrote:
>
by "Tone Compression" I mean the mapping of Lightness values that takes
>
place from Input space to Output space. As you already know, the Lightness
>
range of a monitor typically goes from L*=0 to L*=96. That of a CMYK offset
>
press typically go from L*=20 to L*=92. Clearly, compression has to take
>
place between these two spaces on a grayscale level at the time of
>
conversion.
It's the job of the perceptual (and relative) rendering intent to map to
L100 and then to the destination. When you build the scanner profile, the
destination color space is unknown.
If you consider that device profiles are dynamically paired, then you can
by definition never know if RGB_x will be paired with CMYK_1, CMYK_2,
CMYK_3 ... CMYK_n. This is a function of having modularized color
conversions through a device independent connection space.
(Don't know about you're figures, presses range to blacker and whiter, for
instance. The L20 black point is too high, and suggests a measuring problem
(see www.iccabc.com abcB).)
>
Kodak Color Flow and Color Synergy from Picto, at least that I know of, are
>
two packages that offer options for generating ICC profiles based on a
>
choice of either HighKey, LowKey or MidKey type of tone compression method.
I'm a bigamist at heart, too, but with PrintOpen and ProfileMaker. It's
nice to know we're two, even if our likings differ -:).
In the past Kodak Input Profile Builder did have the three button options
you list. But they were for profiling scanners that didn't allow the use of
a scanner profile and active use of the scanner controls at the same time,
the way a scanner should.
What you are asking of the profiling application is functionality that
belongs in the scanning application.
In the ProfileMaker 3.0 ReadMe you will find a note on how the ProfileMaker
2.3.5 options 'Variable Range' and 'Dynanimc Range' have been integrated. I
think the ReadMe is in the PM 3.1 install, too.
Hope this answers your question (but I'm guessing it doesn't still -:)).
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