RE: Albumen sensitiser question

[John Brewer <john@johnbrewerphotography.com>]

Thanks for all the info Eric. I did wonder if titration was the method used to test for AgNO3 depletion. For the moment I’ll stick with brush coating. So far I’ve not had any major issues, only idiot errors J.

 

Thanks,

 

John.

 

From: eric nelson [mailto:emanphoto@gmail.com]
Sent: 03 February 2009 05:29
To: alt-photo-process-l@usask.ca
Subject: Re: Albumen sensitiser question

 

The best source of albumen printing info is here.  The whole book is there and covers pretty much everything including the use of kaolin, salt printing etc..  Book is out of print, I've met w/the author years back, and I've only referred to historical books to compare info.  

 

Check chapter 6 for the kaolin stuff which is ONLY to remove the organics from the agno3 solution.  15% is a little strong to me but perhaps for brush it's better.  I'm a floater myself. 

 

Depletion of silver is checked by titration analysis.  HAVE FUN W/THAT!  Wheee!  A horrid process.  Reilly gives a timetable for that and a rule of thumb method.  I doubt one needs to be as meticulous w/albumen's agno3 as with sensitizers for wet plates, but it doesn't hurt.

 

There is another method of coating and sensitizing with 2 sheets back to back and sealing all 4 edges w/thin strips of dry mount tissue thereby preventing any solution from reaching the backs of the paper while submerged.  This allows for a thin vertical tank of albumen and agno3 to be used as opposed to floating in a tray.  Or you can wear gloves and submerge the paper in a tray and hold it there for the coating and sensitization times like I have done.  

 

Eric

 

On Mon, Feb 2, 2009 at 7:58 PM, John Brewer <john@johnbrewerphotography.com> wrote:

Hi Eric

 

Thanks for your input. The recipe I'm following comes from Christopher James book http://www.christopherjames-studio.com/build/thebookreviews.html .

 

Lots of questions I'm afraid!

 

I'm interested in the way you maintain you AgNO3 bath with kaolin, that sounds like it will save me a lot of agro. I practice wetplate photography and maintain meticulously a silver bath for that. It's wetplate negs I'm albumen printing. How do you maintain you bath? What is your recipe AgNO3/H20/kaolin/anything else? I understand why you use the kaolin but how do you measure the AgNO3 depletion? Is this by throughput, specific gravity and pH or by feeling/experience/sense? Can the same sensitiser be used for salt printing?

 

J.

 

From: eric nelson [mailto:emanphoto@gmail.com]
Sent: 02 February 2009 23:22
To: alt-photo-process-l@usask.ca

Subject: Re: Albumen sensitiser question

 

I wouldn't know if there are crystals at the bottom of my agno3 as there is a layer of kaolin at the bottom.  You will need that too if floating your sheets on the agno3 surface to sensitize.  This is because the organic materials in the paper and albumen will darken the solution over time and lower it's effectiveness.  After the solution begins to darken, shake the bottle and let the kaolin settle overnight taking the discoloration with it.  Reilly has a historical illustration of how to set up a siphon for that and mine is nearly identical except that I used a glass milk bottle. :)

 

When you say James, do you mean Reilly?  

 

Since it takes 2-3 minutes of floating the paper on the agno3 solution to properly sensitize albumen, brush or rod coating would be a very uneven coating.  I tried brush coating only once with inferior results UNLESS one wants that kind of look, which could be cool.  But for straight printing/imaging floating gives the best results.

Eric

 

On Sun, Feb 1, 2009 at 4:54 PM, John Brewer <john@johnbrewerphotography.com> wrote:

Hi folks

 

I made up some silver nitrate sensitiser according to James p 471, that is 15% silver nitrate plus 5% citric acid in distilled water.

I see there is now some crystals at the bottom of the bottle. They weren't there when I made the solution up and sensitised some paper. I can't seem to dissolve them, even with heat and vigorous shaking. What are they? Are they anything to worry about? Can I filter or decant them out?

 

One other thing, James says that coating with a rod is possible. This would be preferable for me at this moment. As the sensitiser is clear, coating under safelights is tricky to say the least. Can I do it under low ambient light as I do quite safely with gum? If not any tips or tricks would be most welcome.

 

Thanks,

 

John.