[alt-photo] Re: Collodion POP/ Collodio-Chloride/ Collodion Aristotype Paper - Instructions, Books, Resources?

[Clarence Rhymer]

Hello Francesco,

I have toned my prints in Gold/Borax, Gold/Bicarbonate and Gold/Ammonium 
Thiocyanate.  Yes, Gold is expensive, but one doesn't use all that much 
per print.  IIRC the Thiocyanate was more black/neutral, but that was 
not my goal, so I can't say for sure.  Remember, like wet-plate, these 
processes are done almost completely by inspection.  It is a lot like 
"cooking with your mother".  One adjusts the process until it looks 
right.  You should tone for between 2-10 minutes.  Any faster (more 
aggressive toner) and it does not tone well.  If it takes more than 10 
minutes you need to replenish.  Since in POP one exposes by inspection 
and tones by inspection the results are rarely the same twice, but with 
experience one can achieve the desired result for that negative.

As to which chloride to use (calcium, lithium, strontium, etc.) I 
believe it was claimed in the old literature that they resulted in 
different coloured prints. I don't recall seeing Sodium Chloride used.  
Mark would be able to give you a quick answer to that one.  Strontium 
Chloride is easily available and not expensive, so I have never tried 
anything else.  I have used both Sodium and Ammonium Chloride for 
albumen prints.

As to substituting Collodion for Gelatin in an developing out formula, I 
would be surprised if this were achievable by plugging it into the 
formula.  The former is made in Ether/Ethanol the latter in water.  It 
is the controlled growth of the Silver Halide crystal in gelatin that 
gives the possibility of a developing out product that is exposed dry.  
Having said that, there were collodion dry-plates produced for a time 
and even colour sensitized collodion plates (bromide IIRC) used until 
the early part of the 20th century.

Cheers,
Clarence

On 30/05/2012 12:05 PM, Francesco Fragomeni wrote:
> Clarence,
>
> One more question, do you tone your Collodio-Chloride POP prints? If I
> tone, I imagine I'd tone in a Gold Chloride/ Sodium Thiocyanate toner as
> was common in it's day. Toning is something that I haven't read much about
> in specific reference to Collodio-Chloride POP. I've just read that it uses
> the same toning procedures as Albumen. I would like as black and neutral of
> a tone as I can achieve. Most of the examples of Collodio-Chloride that
> I've seen have that characteristic but I'm unsure if it is the raw
> process's inherent tonal characteristic or if it is from toning. The Reilly
> book references Thiocyanate toners as most common with Collodion-based salt
> formulas. As I understand, Gold-Chloride/ Sodium Thiocyanate toners produce
> neutral blacks. If that is the key then the Gold-Chloride is going to be
> the most expensive component of the whole process.
>
> Let me know your thoughts.
>
> Best,
> Francesco