There are instructions on the Bostick and Sullivan Web page for developing
litho film with Pyro. Dick Sullivan has confirmed good results with this
combination in platinum printing.
As for the other question, you need a color densitometer to read a Pyro
developed step tablet. Many of us have in fact compared the curve as read
through the regular B&W filter and in color mode and commented on this.
There was a thread on this topic sometime early this year as I recall.
As you suggest, the effect of the stain does vary from medium to medium in
accord with the spectral sensitivity of the different emulsions. Also, the
stain itself varies according to the method of development, from brown to
yellow/green and this introduces another variable. My experience with
carbon printing is that exposure times with Pyro negatives are somewhat
longer than those with conventionally processed ones,and the same
observation has been made by several platinum printers. I do not recall any
comments about Pyro and some of the other alternative processes.
Sandy
>> > 1) would you recommand Pyro (PMK) as a developer? If no, which other, or
>> > some other developer along with Pyro?
>
>I told him I'd HEARD that someone had good results with pyro on lith and
>that the information was linked to the Bostick and Sullivan Web page,
>address
>
><http://www.bostick-sullivan.com>
>
>tho perhaps Dick will confirm if that is so...
>
>I myself use dilute Dektol (1:7 to 1:10), and have had good results with a
>soft-working glycin developer, which I didn't test as much as I meant to,
>tho it looked VERY promising. (If anyone asks, I'll dig up the formula &
>post.) I know others have reported success with other developers, but
>reports on lith and pyro have been scanty, as I recall.
>
>The next question was,
>
>> > 2) Is it possible to use along with Pyro the method of density > >
>determination with the step wedges you described in PFP #1 (I mean, > >
>considering the stain which Pyro builds, which, so I read, lets the neg >
>> appear more flat than it prints)?
>
>This I think could probably not be done as I describe, because you
>couldn't read the *printing* density of the negative by eye. I also
>guessed that the effect would vary from medium to medium as the spectral
>sensitivity of the different emulsions varies.
>
>My thought was that if one had a densitometer, it would be easy (and
>interesting) to compare the printing effect of similar *readings* on two
>step negatives, one with the stain and one without... One of the "to-do's"
>on my back burner. I recall that Maxim Muir reported a definite
>intensification effect from sulfide toning a negative -- which also, I
>assume, would not read correctly on a densitometer. I've had similar
>effects from selenium toning and chromium intensifying negatives: the
>changes of color apparently equalled more film density in printing, but
>I never tested this in a methodical way.
>
>So my other thought was that with all the pyro-niks on this list, there
>should be some better answers available. I also suggested that it might be
>prudent not to BEGIN with pyro, because it might have too many variables
>for a first effort, but that I was reluctant to discourage something I'd
>like to find out myself.
>
>Thanks in advance,
>
>Judy, et al.