Argyrotype and Bergger COT 320

I had time to test Bergger COT 320 only. See the result here:

http://www.loris.medici.name/Argyrotype_on_COT320.jpg

Dmax is very nice - I think Argyrotype is a remedy for my "double
coating illness" with Vandyke. Kudos Dr. Ware.

I noticed two problems with Argyrotype + COT 320 combo:

1) Bleeding (albeit in a much lesser extent than Vandyke in many papers
- but it's there).

I drained the washed (about 3 minutes, 3 water changes) print for before
fixing for 1 min. and the paper stained in the direction of draining
(see the left / lower-left edge of the image).

2) Staining in the image area under dense parts of negative

I think most of the staining is due to bleeding. Will also try to use
less sensitizer. FWIW, I will also try to process in citric acid.

I used a brush to coat Argyrotype emulsion to COT 320. Absorption is
poor, the paper doesn't absorb Argyrotype as easily as it does with
Ziatype (or New Cyanotype) emulsion. I guess addition of something like
Tween can help in curing both problems 1 and 2. COT 320 is not an easy
to coat paper anyway (very very smooth)... Probably amnt. of sensitizer
also is critical. It took long time to coat paper, I made many passes.
Will try a glass rod + using less sensitizer next time.

When Argyrotype doesn't work on a specific paper, what problems you get?
According to what you see, do you think COT 320 can be made to work with
Argyrotype?

TIA,
Loris.

-----Original Message-----
From: Loris Medici [mailto:mail@loris.medici.name]
Sent: 03 Nisan 2006 Pazartesi 14:38
To: alt-photo-process-l@sask.usask.ca
Subject: Mixing Argyrotype (my experience)

I mixed a 200ml batch of Argyrotype yesterday evening.

...

Will try to print a couple of step tablets this evening (on Whatman
Watercolor and Bergger COT320). I'm very curious about the dmax I will
get. If it gives good Dmax (in my subjective terms) without double
coating, then will definitely use it.

...
Received on Tue Apr 4 00:09:00 2006