Calotype problems

[GCyberfish]

A few Weeks ago I tryed the Talbot´s Calotype Process - and completely failed.
I used paper for painting.
Washing the paper in silver nitrate solution, then iodizing - everything was okay. But when I washed the paper with Talbot´s "Silver-gallo-nitrate"
(I ve already used the recipe for toning prints), and the paper went totally black - all the silver chloride in the paper had been reduced.

recipes:
Bath one
silver nitrate 6,5g
Water to make 200ml

bath two - iodizing
potassium iodide 32,5g
Water to make 600ml


Silvergallonitrate

Bath a
silver nitrate 6,5g
Water 60ml
Acetic acid 60% 10ml

bath b

saturated solution [ acidum tannicum] - german "Tannin" - don´t know the english word for it-


I hope you can help me.

 

[Jim Noel]

I don't know if I can help or not, but-
I see no listing of gallic acid in your process and this is a necessary ingredient in the calotype process. Is this the "tannin" in part b?

What kind of light levels were you working under? I use a red safelight, 15 watt at 4+ feet.

Was each step dried in total darkness?

Was the silver-gallo-nitrate the same actual solution in which you had toned prints, or fresh solution. If previously used, this may be the culprit.

I hope these questions help you to track down your problem.

 

[GCyberfish]

the "Tannin", I found out, is simply tannic acid, and I used it as a substitution
for the gallic acid.
and I used red safelight...
...but is the drying in total darkness really nessesary for the Process?
I used a device for dry pressing paper as a heat source, so the paper is dry after a few minutes.

Could´nt it be the paper? Residual chemicals from the paper-bleaching process could be the causation for the undesired reaction.
To get further I have to get to know more about the production process of paper...

 

[markm]

I will admit up front that I have no hands on experience yet.

According to "Coming into Focus", the sensitized paper should be moist when exposed.

Prepare the paper with a 7.5% solution of silver nitrate and 5.6% solution of potassium iodide.

For sensitizing and developing, the book refers to 4 solutions:

A) 11.4% solution of silver nitrate
B) 28.4ml A, add 5.5ml glacial acetic acid
C) Using 100 ml water, make a saturaed solution of gallic acid
D) Add 3 drops B and 3 drops C to 4ml water

To sensitize the paper (under safelight), coat the prepared paper with D and let sit for 2 minutes. Blot the paper and let dry in the dark. "The paper will be slightly moist when put into the camera."

To develop (under safelight), mix equal parts B and C and brush onto the negative. An image should appear at once. With a clean brush apply C - do not over-wet. Allow the image to develop until it stops increasing in density - apply more C.

When you have a good contrasty image, rinse in plain tap water, fix with hypo for 5 minutes, then rinse for an hour.

- Mark

 

[cynan]

Calotype Club on Flickr

For any calotype related questions, check out the 'Calotype Club' on flickr.

http://www.flickr.com/groups/1384661@N22/

 

[Jerevan]

Do a search for Calotype here on APUG and you'll find some good info, for example this: (there was a url link here which no longer exists). Without having tried it myself, it seems to need a very clean working and orderly person to get things going. Many of the older processes are also very dependent on the quality of the paper.