Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Ernst Dinkla" <
E.Dinkla@c...> wrote:
 
> Did you try it and did it work ?

Ernst, this is all old Dan Culbertson stuff. You can create profiles 
for quad inks. You can edit curves into those or any other printer 
profile with Doctor Pro, other software as well I'm sure.
However, sep curves created to work on files in a working space (as 
most used here are) will not work. The idea is to be able to convert to 
the profile for printing, converting to a quad (or any other) printer 
profile will significantly alter the RGB values in the file, therefore 
those curves will not result in the desired final RGB values for 
printing as they did when applied to the working space they were 
created in. They were created to work on AdobeRGB (or whatever).
So you'd want to edit those curves into a profile that does not 
originally alter the RGB values, like a working space. Doctor Pro will 
not edit working spaces. Alternatively, you can create a null printer 
profile, and edit your curves into it. Unfortunately since it was not 
created from the inkset/paper, it will not have the advantage of 
preview. It's only usefulness will be to print through, no more 
advantage than running a curve anyway. A null printer profile is not 
that easy to come by either.
Another option is to start from scratch. Create the profile from the 
inkset, attempt to create sep curves that print well on a file already 
converted to that profile, then edit those in. Unfortunately the new 
RGB content after conversion is not very useful for creating optimal 
quad sep curves.
However, you can do all this on CMYK profiles using old Culbertson 
tricks.
Creating really good RGB quad printer profiles, that also preview well, 
will be much more complex than it may first appear, and editing in sep 
curves made by trial and error does not take good advantage of all the 
data provided by the initial profile anyway.
Tyler