[Alt-photo] Re: Argyrotype on Fabriano Artistico Extra White Soft Press 300gsm (140lb)

[Keith Gerling]

Thanks, Loris.  This is very useful!


On Thu, May 16, 2013 at 7:27 AM, Loris Medici <mail at loris.medici.name>wrote:

> Hi all,
>
> For the last couple of days I was dealing with the calibration of
> Argyrotype process on Fabriano Artistico Extra White Soft Press 300gsm
> (140lb) paper (FAEW onwards...) acidified with sulfamic acid and wanted to
> share few notes for the records.
>
> I was having bleeding, grainness and all kinds of other problems with this
> paper / sensitizer combination, no matter how much Tween I was using.
>
> This paper has a remarkable amount of AKD sizing which makes application of
> the Argyrotype sensitizer pretty problematic. As you may already know,
> Argyrotype doesn't get easily absorbed into the paper's fibers easily,
> probably because it has a significant amount of ammonium iron(III) citrate
> (AFC onwards...) in the formula. Somehow, when the AFC content in the
> solution increases, the paper is less and less inclined to accept it
> readily. That's why it is advised to (additionally) use a surfactant such
> as Tween 20, in order to facilitate the take up of the emulsion into the
> paper's fibers.
>
> When you compare the AFC content of Argyrotype against some other
> sensitizers with it - which normally don't need any surfactant to work nice
> - you notice an interesting condition:
>
>
> AFC % AgNO3 %  Argyrotype 22 10.3  Trad. cyanotype (1+1) 10 - 12.5 N/A
> Vandyke 9 3.8
> Argyrotype contains approx. 1.8-2.4x more AFC than the comparison. (And
> 2.7x more silver!)
>
> Knowing Sam Wang's preference for using Argyrotype sensitizer diluted 1+1
> with water (an information shared here by Christina Anderson before...), I
> decided to dilute my sensitizer 2+1 (1 part water per 2 parts standard
> strength stock sensitizer solution). Even diluted 2+1, the sensitizer would
> still have 1.8x more silver than Vandyke, and my previous experience with
> pop Pd was that there's only a marginal difference in dmax between iron
> sensitizer strengths of 45% and (recommended) 60% - tested with matching
> strength of Pd solutions. Therefore, I assumed it wouldn't hurt much in the
> dmax department.
>
> Indeed, now the diluted sensitizer works like a charm (Pd quality I would
> say...) with this paper, and the resulting dmax leaves nothing to ask more!
>
> This dilution trick also made me (finally) able to get absolutely neutral
> to blue black and uniform results with gold-thiourea toner.
>
> Therefore, if you have problems with Argyrotype, also try it by diluting
> 2+1 or 1+1, and see if that works and/or you like the results!
>
> Regards,
> Loris.
>
> P.S. I still add 1d 10% Tween 20 per ml of sensitizer, FAEW has a very hard
> surface therefore still needs some help. (OTOH, I actually didn't try it
> w/o Tween, but I'm not going to fix it since it ain't broken!)
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