From: Katharine Thayer (kthayer@pacifier.com)
Date: 07/02/02-01:45:02 AM Z
Hi Cor,
My interest has been in seeing a straight gum print from a pyro
negative. So far everyone I've been aware of who prints gum from pyro
prints gum over something else, and maybe I haven't seen enough of those
and (huge caution here) I've seen them only in reproduction, but the gum
layers of the ones I've seen don't look like a gum print to me, but like
a layer of colored gum laid down on the previous print. That combined
with my own experiments with digital color table spectral density
negatives and Joe's and others' tests showing differences between the
spectral sensity of platinum and gum have left me wondering about some
things about spectral density and gum, which have never been answered
here to my satisfaction. Don't have time to elaborate further at the
moment, but just to say I'd still like to see a straight gum print from
a pyro negative. Thanks,
Katharine
Breukel, C (HKG) wrote:
>
> Hi all,
>
> Thought I could share some initial results on my tests with gum over
> Kallitype with a Pyro negative (I believe Katharine Thayer inquired
> about using a Pyro negative for gum?)
>
> The negative is a 4*5 inch MACO 820IR film (yes infrared film) processed
> in PMK Pyro. Got some realy excessive stained highlights, not realy
> uncommen with Infrared.
>
> Printing it on silver gelatine, VC, asked for excessive burning of the
> highlights (tree leaves) of 2 stops with a filter 1 over the base
> exposure (2 1/2).
>
> Pre-shrunk and foam-brush sized (1.4% gelatine/Alum harded) Fonteney
> paper was used.
>
> Initial print was a slightly under exposed Kallitype (as written up by
> Peter Marshall, originally by Thompson, see B&S web site for protocoll).
> Printing time was relative excessive: 20 min, wheras a non Pyro neg
> would usually print in the 5-15 min range.
>
> Gum print was aimed at "filling in" the higlights: mixture 0.5 ml gum,
> 0.02 gram (!, long live the micro balans) Burnt Sienna and 0,5 ml
> PotDichromate.
>
> (BTW I realy wonder how people can maintain registration: even after a
> pre-shrink step, and using only 4*5 I could not obtain perfect
> registration)
>
> Printing time was again excessive (no surprise, taking the heavy stain
> in account) : 40 minutes (in my setup a gum print usually prints in the
> 5-10 min range). Overnight soak to clear (probably shorter would also
> work, this was just covenient)
>
> The resulting print was actually quite pleasing: shadow/mid tone black
> grey, high mid tone/highlights light yellow.
>
> So, yes one can make a gum print ffrom a Pyro negative, at the expense
> of long printing times. Not a realy shocking discovery, but nevertheless
> of interest I hope.
>
> Best,
>
> Cor
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