Digital BW, The Print

I guess I'd err on the side of a duotone/tritone files. If you depend
on just the process black ink printing on your black plate only,
you'll end up with gray, not black. 

You could ask the printer to print in a Pantone black rather than a
process black, and do it in one color only. YOu might want to consider
 doing duotone files with the varied Pantone blacks. There is a good
range of shades of black and you can create some really nice
variations in your files with just that touch of color. then, you
don't have to worry as much about the ink coverage on the rollers on
the press (if this is traditional web printing, which it most likely
is, considering your issues with variation in color). By using Pantone
blacks, even if it goes out of register, or the ink varies a bit on
the rollers, you'll still get the same tone on each image and not have
the issues of blue/yellow/magenta toning your images. 

And, the text on your pages will still be true black, because you'll
be specifying them in a Pantone black, rather than process black.

just one more option.
Jane

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, David Burges
<davidburges@...> wrote:
>
> This one is especially interesting, there is concern about the way the  
> printing company manage the flow
> as the files are swinging from yellow to blue???
> 
> > --- In DigitalBlackandWhiteThePrint@yahoogroups.com, C D Tobie
> > <CDTobie@> wrote:
> > >
> > >
> > > On Feb 23, 2009, at 10:13 AM, d.burges wrote:
> > >
> > > > Hi, Does anyone have an answer to obtaining neutral tone B+W  
> > images
> > > > when printing as a CMYK file. I'm a photographer in the UK putting
> > > > together a 62 page photobook for a client who wants the book in B 
> > +W,
> > > > the company which produce the books for me need pdf files  
> > created in
> > > > photoshop coverted to CMYK as they print on a commercial printing
> > > > press,
> > > > I've just had the books back and many of the pages have printed  
> > with
> > > > slightly differing hues, mainly yellow, some blue. Having read  
> > many
> > > > posts it would seem it is very hard to obtain neutral tones due  
> > to the
> > > > difficulty of mixing the CMY inks to produce neutral B+W,  
> > however I'm
> > > > hoping there is an answer out there somewhere! David
> > >
> > > Color management will typically improve results, but if similarly
> > > prepared files are coming out warm in some pages and cool on others,
> > > than it would appear that the presses are not being run in a color
> > > managed manner, or to tight enough standards to get consistent
> > > results. The simple way to assure that files don't get color casts  
> > is
> > > to create black-channel-only separations, where the entire image is
> > > printed with only black ink, no colored inks blended in. This does  
> > not
> > > allow control of the tone (whatever gray the black ink produces is
> > > what you get) and may result in less smooth images, as there is only
> > > one ink being used, but if your current results are unacceptable, it
> > > might be an improvement.
> > >
> >
> > I would tend to agree here. Since the color casts vary, you might need
> > a better printing company or to change the way you do things with the
> > press. The heavy GCR is a step in the right direction, but as
> > mentioned above you might need to convert everything into the black
> > plate to get really neutral prints on a press that swings from yellow
> > to blue.
> >
> > Instead of fighting the color issues, would it make sense to go with a
> > duotone? That way you might be able to control the color cast so that
> > all the pages were at least the same/similar color. It should improve
> > the apparent resolution in the lighter tones too. Maybe a tritone with
> > one color in the highlights and another in the dark tones.
> >
> > One question also comes to mind... Is it really on a plate press, or
> > is it on a digital electrophotographic "press"? A lot of the
> > electrophotographic systems get put on the cheap end when the company
> > doesn't buy the good color managed RIP to drive them, or they don't
> > invest in color management tools and techniques to keep them neutral.
> >
> > Definitely find out what the maximum ink load is for this machine with
> > your preferred paper. You might even ask them for the lab values of
> > each ink, and the secondaries so that you can build the proper CMYK
> > set up into Photoshop. You never know, they might actually know the
> > answer to that question.
> >
> >
> > 
> 
> 
> 
> [Non-text portions of this message have been removed]
>