Re: Sprint/Pyro (was Your opinion please

John Rudiak (wizard@laplaza.taos.nm.us)
Sun, 2 Jun 1996 21:57:23 -0600 (MDT)

On Mon, 3 Jun 1996, Judy Seigel wrote:

>
> Perhaps you've mentioned "Sprint End Run" in other context; hope you
> won't mind describing again... What's it for? Could you put it in
> gelatine to discourage bubbles?

Judy, Sprint End Run is a Photo-Flo like solution that has formaldehyde
in it so that it could be used as a stabilizer for color processes as
well as black and white. Formaldehyde is a hardener for gelatin, so I
would probably not try it in gelatine. It may also be a hardener for
albumen but in the quantities I used it I did not notice any hardening.
Maybe some on the list more aquainted with this may like to comment.
> >
Also, > > ... in my own work I discovered that if I took a normal
> > negative developed for contact printing on silver gelatin paper and
> > chromium intensified it using pyro as the redeveloper, it produced a
> > negative perfect for albumen.
>
> The implication here is that pyro as redeveloper was in some way better
> than normal "regular" redeveloper. In what way? The stain added even more
> density? I've tested chromium intensifier, one time, two times, with added
> selenium toning, etc., don't remember off top of the head which developer
> was best, but know I never tried pyro ... should I?
>

The supposed advantage of a pyro negative with UV based printing systems
is that the yellow stain blocks the UV, the stain is formed in proportion
to the exposure, enabling a longer scale to be printed. This combined
with the strong self-masking inherent with this printing out system
creates a print which has a "look" that is unique. A majority of the
original negatives (glass and nitrocellulose base) which made the vintage
platinum and albumen prints we are familiar with today were developed in
pyro. A lot of these negatives are so dense and contrasty that they are
unprintable with modern methods. The point is that intensification and
redevelopment in pyro is an expedient way to produce a "neo-vintage"
negative to explore albumen printing with it's historically
characteristic look.

Best

John