Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Walt Farrell
<wftemp1@h...> wrote:
> Johnny Eades wrote:
> > You DO CONVERT the target to Gray Matte before printing. That
> > is what you normally do to print QTR, right? Don't feel it's
> > a dumb question, often I read something and try to understand
> > it several times and often try several different things before
> > I really see what the process is. As Thomas Edison said after
> > 25000 tries on the electric light bulb, "Now I know 25000 ways
> > NOT to make an electric light bulb."
> >
> 
> This has me somewhat confused.
> 
> I do NOT convert the target to Gray Matte before printing with
> QTR (on the PC).
> 
> Is this a Mac vs PC workflow difference?  (Ferdinand, to whom you 
> responded, is a PC user.)
> 
> 	Thanks,
> 	Walt

I thought I undertood this, but maybe I don't.  Yes, I'm a PC user. 
On a Mac, presumably you'd be printing a grayscale image which is
originally in the lab-gray space, using "print with preview" in PSCS,
and converting to gray-matte as part of the printing process.  You can
print direct to QTR, and do the profile conversion on the fly.

On a PC, you have to convert the grayscale image in the gray-lab space
to gray-matte yourself, and first save to file before giving it to
QTR.  I can't see a huge amount of difference in the Mac vs PC
workflow, but perhaps I've missed something.

Is it something to do with the differences between gray-lab and
gray-matte?  On a PC you'd be making adjustments to the output levels
on the gray-matte file.  On a Mac, you'd be doing it on the image in
the gray-lab space, and doing the profile conversion on the fly when
printing?

I found that if I don't convert the target chart to gray-matte, then
my Epson 2100 (UC, EEM) can print distinguishable blacks virtually
down to zero.  If I do convert the test chart to gray-matte, then it's
black from about level 5 down.  This probably isn't a huge difference
for most images.

Even so, perhaps someone can explain *WHY* we need to convert the
chart to gray-matte.

F_P