Digital BW, The Print

I can view the "target" by opening the .txt reference file in Colorlab and
see its patches.  (The 4800 Mac download is completely screwed up and
doesn't work.  Epson Support are on to it.)  As for Rolf, I have been
reading his posts and he seems a little confused (or is at least confusing).
See his latest. Greg/Ernst, I would agree from viewing the test chart that
it is not doing an RGB profile but rather (a form of) CMYK linearisation
which I would label part of "calibration" and not "profiling".  I don't
"get" Rolf's split of these.  (Pity they don't give us control over ink
limits as well !!) 

Arguably it is using 66 patches per colour (C, M, Y and K) with the scale
for 2 of them comprising two inks and 3 inks for K.  However, I do not know
if this is how the underlying CMYK driver thinks. 66 observations is quite a
number.


> From: Ernst Dinkla <E.Dinkla@...>
> Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Date: Tue, 04 Oct 2005 16:35:33 +0200
> To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Subject: Re: [Digital BW] Re: more colorbase misc. - printing target
> 
> Steve Kale wrote:
>> You may still have to print from the utility (contrary to my earlier post)
>> and hence a separate edited tiff might not work.  I can't see if the tiff is
>> printed by Colorbase as a CMYK file (a la QTR Calibration) or as an RGB file
>> through the driver.  To be doing linearisation it needs to be doing the
>> former.  A straight colour scale with just C/c, M/m, Y or K/k/kk per patch
>> respectively.
> 
> Target is CMYK, 8 rows of patches, 33 patches per row = 264.
> The GRAD file next to it has 8 lists that say C,LC. M, LM etc.
> It will print the target with Colorbase. The split to the 8
> channels will be based on the CMK percentages in the target, Y
> isn't split.
> 
> an excerpt from the Colorsync list:
> 
> Well, a simple look at the reference data lets me draw the
> conclusion that
> this is more a linearisation tool than a calibration tool.
> 
> The patches in there look like cyan, magenta, yellow and grey
> patches.
> Just not enough colors to build a lookup-table.
> 
> Rolf