[alt-photo] Re: Chemical Development for Printing Out Processes

[Francesco Fragomeni]

Ryuji,

Thanks for the reply. So your thought is that the higher ph and potency of
a modern developer (unused) would cause fog in a POP emulsion. Interesting
and I hadn't considered that but it makes sense as a possibility.

By the way, I'm not particularly interested in recreating the results of
historic literature or figuring out what works best for the purpose, hence
the question about using modern developers with POP emulsions. Its a
mismatch intentionally. My interest is simply in seeing what the results
might be simply for the sake of curiosity.

Has anyone actually tried this who can confirm Ryuji's fog hypothesis? Or,
do any of you Albumen practitioners have an extra test strip and some
Amidol or other print developer sitting around that you can test with next
time you print? I'm still setting up my space otherwise I'd try it.

Thanks for contributing Ryuji and anyone else who chimes in.

-Francesco


On Fri, Sep 7, 2012 at 8:43 PM, Ryuji Suzuki <rs at silvergrain.org> wrote:

> I've not done this myself but based on what's known about electrochemical
> model of development process, you'll get mostly fog if you process POP
> material in a modern print developer for developed out process.
>
> If you were to adjust formulation for POP, I'd suggest decreasing the
> developer pH significantly, and dilute the developer somewhat. I'd actually
> use standard print developer that's already fully used and exhausted in
> regular develop out printing process, dilute it, and perhaps further reduce
> the pH by adding baking soda or some mild acid.
>
> Historic gallic acid developer is often mixed with some silver nitrate
> solution (so called physical developer). When chemical development process
> became common use, that style of developer went out of fashion. This point
> is probably good to keep in mind when recreating the results of historic
> literature, but it is probably more important to use modern knowledge to
> figure out what works the best for the purpose.
>
> --
> Ryuji Suzuki
> "No matter how much you study or improve vacuum tubes, you will not arrive
> at a
> transistor." (Leo Esaki)
>
>
> Francesco Fragomeni wrote:
>
>> Hi all,
>>
>> It's been a little while since I've last written and I've been kept rather
>> busy with my move to NYC but I've been keeping a close eye on the
>> conversations.
>>
>> This question pertains to using chemical development for processes that
>> are
>> traditionally considered printing out processes. The literature tells us
>> that this was indeed a practiced technique albeit a rare one due to the
>> preference of the time for non-black toned prints. One practitioner I can
>> reference was the commercial printing operation of Blanquart-Evrard and
>> Fockedey outside of Lille, France in the 1850's. They used Albumen with
>> chemical development rather then as a printing out process in order to
>> mass
>> produce prints quite successfully.
>>
>> I'm particularly interested in silver-based POP processes like Albumen and
>> Collodio-Chloride which make use of silver-chloride as the light sensitive
>> agent. The presence of silver-chloride allows the possibility for chemical
>> development and I'm quite curious to hear if anyone has experimented with
>> this. Apparently, Blanquart-Evrard and Fockedey were able to produce
>> lovely
>> grey and black tones by developing Albumen paper (exposed much shorter
>> then
>> normally) with a gallic acid based developer. I'm curious what might
>> result
>> by developing in modern developers that are established to work quite well
>> with silver-chloride emulsions i.e. Amidol, Dektol, etc.
>>
>> I'm inclined to experiment with this but I'd love to hear about any
>> results
>> anyone else has had.
>>
>> Best,
>> Francesco Fragomeni
>> www.francescofragomeni.com
>> ______________________________**_________________
>> Alt-photo-process-list | http://altphotolist.org/**listinfo<http://altphotolist.org/listinfo>
>>
> ______________________________**_________________
> Alt-photo-process-list | http://altphotolist.org/**listinfo<http://altphotolist.org/listinfo>
>