Digital BW, The Print

Hi Ellie,

I'm wondering if the RGB file you send to the printer is basically gray
where R=G=B or at least close.   Or do the 3 RGB channels separately
control different inks to significantly control the density.

The main "new" thing was to use the RGB profiling that i1Match
already does to a Grayscale.  The reference file is actually still an
RGB definition but only values with R=G=B are used.  When the idea
first came up,  we actually used the ordinary RGB targets but I think
that had two difficulties.  First was how to drive a real grayscale print
method with an RGB target file.  Converting to Lab and keeping L
worked pretty well but its not exactly the same thing.  The other
problem was that the Eye-One reader scans patches that must vary
enough for the read to recognize transitions.  Reducing the target and
reference to just 21 gray values solved both issues.

So if your RGB files are essentially gray you should be able to just
convert the targets to RGB and print, and do the same proofing that
is described.

However, if your RGB files somehow encode different inks I would
think you might have to go back to the regular RGB references and
target -- just use i1Match as normal.  The difficulty will probably be
reading the patches, although you can do it without scanning.
The other issue is how well the i1Match software can deal with
colors other than real RGB.

I suspect you'll need to do various experiments and see what works
and how well.

Roy


--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "colorspanmam" <Ellie@I...> 
wrote:
> Hello Roy
> 
> This is my first introduction to the group, as I joined it when 
> someone posted a reference to this posting on the Colormanagement 
> group in answer to a question I had put.
> 
> We have a fineart and photographic printing and giclee reproduction 
> business and have been in this business for over three years now. In 
> the past year we have been also printing B&W for photographers.
> 
> I have downloaded the files and am looking forward to testing this 
> out. I am running a Colorspan printer with four blacks, and wanted 
> just such a profile for myself to use in soft proofing the images I 
> am about to send to the printer.
> 
> The differences I can see here are that I am working with ARGB files 
> (converted from the scanner profile) as I scan the B&W negs in RGB 
> 16 bit. I do not convert to greyscale, but send the files to the 
> printer in RGB. The RIP handles them this way best, and I then use 
> the profile for the media I am using, in 4 black inks in the RIP. 
> This profile is a proprietary one for the RIP and can't be used to 
> soft-proof in PS.
> 
> Would it give the same results if I convert the target files from 
> greyscale 2.2 Gamma to ARGB 1998 before sending them to the RIP to 
> be printed?
> 
> I also am using Gretag Macbeth Profilemaker Pro 4.1.5 with the Eye 
> One. I presume I can use this to generate the profile in the same 
> way, using your instructions?
> 
> If so, when converting to the ARGB profile, should I print one file 
> in each of the two rendering intents (perceptual and relative) to 
> generate a profile for each of the two possibilities of conversion 
> for the files I send out?
> 
> Best regards,
> 
> Ellie Kennard
> Innovative Imaging Studio
> http://www.iistudio.com
> 
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Roy 
> Harrington" <roy@h...> wrote:
> > 
> > Hi All,
> > 
> > I've done a short write up with all the needed files and 
> information.
> > Download from here.
> > 
> > http://harrington.com/SoftProofing.sit
> > 
> > I've done this on a Mac but there's no reason this shouldn't work 
> just
> > as well on Windows -- locations as probably different.
> > 
> > Roy
> > www.harrington.com