U of S | Mailing List Archive | alt-photo-process-l | RE: Vandyke Question

RE: Vandyke Question



I cannot give you an specific answer, but I have used 2+ year old Van Dyke chemistry and found it satisfactory. Age is probably not your problem - look for contamination. Joachim
-----Original Message-----
From: Scott Wainer [mailto:swphoto@verizon.net]
Sent: Friday, February 22, 2008 6:20 PM
To: Alt Photo List
Subject: Vandyke Question

Good day List,
 
I recently decided to print some images in vandyke and found a 2 year old bottle of sensitizer hidden on the shelf. Thinking it was too old to use, I mixed up a new batch only to find that when I added part c the sensitizer turned cloudy and eventually separated with a clear liquid on top and a grayish tan sludge on the bottom. I tried making a second batch thinking I added part c too fast but I got the same result. I thought the water I distilled might have been contaminated so I tried again with store bought distilled water and it happened again. Frustrated, I ordered all new chemicals from Artcraft and tried again today - same result. If I let the sensitizer sit for 24 hours then filter it I get a clear liquid which lacks contrast and is rather thin density wise. Anybody know what's going on here?
 
My formula is:
 
Part A
9 gm - Ferric Ammonium Citrate
33 ml - distilled water
 
Part B
1.5 gm - Tartaric Acid
33 ml - distilled water
 
Part C
3.8 gm - Silver Nitrate
33 ml - distilled water
 
Mix parts a, b, & c separately. Add part b to part a slowly with constant stirring. Add part C very slowly with constant stirring.
 
Any help would be greatly appreciated.
 
Best to all - Scott