Digital BW, The Print

> -----Original Message-----
> From: Roy Harrington [mailto:roy@...]
> Sent: Monday, August 25, 2003 10:31 PM
> To: DigitalBlackandWhiteThePrint@yahoogroups.com
> Subject: Re: [Digital BW] Septone system
>
>
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Martin Wesley"
> <mwesley250@e...> wrote:
> > > -----Original Message-----
> > > From: Roy Harrington [mailto:roy@h...]
> > > Sent: Monday, August 25, 2003 1:36 PM
> > > To: DigitalBlackandWhiteThePrint@yahoogroups.com
> > > Subject: Re: [Digital BW] Septone system
> > >
> >
> > Roy,
> >
> > You may recall the 7600 samples of the Septones I showed you at the SF
> > meeting. The hue of the prints looked very good but some of the
> PixelPicasso
> > wedges were only okay but not as good as others varying with
> how the inks
> > were blended by the software. The 2200 wedges they sent me are
> actually much
> > better but not all are as smooth as I would like to see.
>
> Yes, I remember the prints.  The hues changes were kind of
> extreme so that it
> was obvious to see.

I doubt any one photographer would use the extreme tonal range the inks can
cover. Same seems to be true for the VM sets as well. From my impression of
the Septone samples I would probably use around a 60/40 blend. Something
like 55/45 shadows, 60/40 midtones, 65/35 highlights. Impossible to know
without trying but varying hue in the print should be subtle.

So I could actually get along with two sets of grays that were much closer
together in hue. Obviously this doesn't work from a marketing point of view
though.

> But the more I think about this septone
> idea the more
> skeptical I become.  I think Shilesh also hit upon the issue --
> warm/cool is
> only one dimension of the color variations you might want.   I
> like to think of
> it like the LAB space.  B gives you the yellow/blue or warm/cool
> dimension but
> A which is red/green is equally as important.  This gives you the
> magenta or
> eggplant hues that careful selenium toning can give in a silver
> print.  I think
> this is the effect I most miss.  I've always disliked the
> olive-like tone of some
> silver papers and selenium toning solved that.

I agree with you. For some reason the grayscale inks have gotten hooked on a
color variation that predominantly shifts on a blue - yellow axis. Being
able to shift hue on two axis would be better. If I had to choose though I
think I would rather be able to shift on one hue axis and be able control
that shift separately in different tonal ranges than to have two hue axis
that effect the entire tonal ranges equally.

Of course not everyone wants a change in hue across the tonal range of a
print. In traditional silver printing many people try for the most neutral
print they can sometime not toning at all to avoid hue splits.

>  Likewise I think
> many of the
> carbon inks give me that olive look sometimes and warm/cool
> doesn't fix it.

Definitely.
>
> >
(snip)
> >
> > Do you think that coming up with curve sets that varied two
> sets of gray 3
> > gray inks over highs, mids and lows could be handled by QuadTone?
>
> I think there's a risk of making things too complicated, but sure
> if you can
> mathematically describe it, it can be programmed.  I might be inclined to
> put it into the curve generation phase instead of run time driver phase.

The math would seem to be straight forward since for any given point on the
tonal ramp you are simple describing the ratio of warm/cool ink to lay down
in addition to the ratio of the two adjacent gray positions. The logic would
be for tones 100 to 66 use a ratio of x1/y1 warm/cool grays, from 65 to 33
use a ration of x2/y2 warm/cool grays, etc. You could have just two zones or
perhaps 4.

In a sense I could see doing this on the fly as R9 seems to have done. The
problem here is that it does get complicated and linearity may suffer. In
fact it does to some extent judging from the samples I have. With QuadTone
you could linearize any particular set of ratios for your printer/paper
which you can't do with the Septones software.
>
>    Or say a
> > VM set with 3 toners over three ranges?
>
> The mind starts to boggle with the possibilities.  My
> inclination, if you want
> maximum flexibility, would be a set of 3 or 4 grays that are the
> purest, no
> color pigment set.  Then maybe 2 or 3 toners whose colors are specifically
> a "desirable" color like sepia or eggplant.  You would design curves that
> used only small amounts of these tones to vary the gray output.  You
> could use generic CMY for the toners but it might be trickier to balance
> two different toners.  Who knows?  I'm starting to think I may have to
> get a 2200 for ink experimentation.

I am inclined to agree with you. Being able to infinitely vary the hue
sounds nice on the surface but practically too many options become
overwhelming. Two toner positions sounds good and if there were several
toner pairs available photographers could choose the hue axis they wanted to
work along.

The 2200 with its small separate cartridges looks like it would be the ideal
test bed for trying different inks.

Another question that comes to mind is which approach, Septone or VM, puts
more non-carbon pigment onto the print?

Martin
http://www.borderless-photos.de/guests.html