Re: Vandyke Question
Scott,
I just mixed up a batch of this exact formula and no precipitate occurred.
BTW, we have used year old VDB and it works fine, so hopefully you didn't
throw the old stuff away?
This problem was reported to the list not too long ago and I cannot remember
what the consensus was but I seem to remember that if you let the stuff sit
for a while it'll go into solution, and that if you stirred the two
solutions together too quickly that could be the cause of the precipitate
falling out of solution. I did heat up my water, though, and perhaps that
is why I did not experience that precipitate.
Chris
----- Original Message -----
From: "Scott Wainer" <swphoto@verizon.net>
To: "Alt Photo List" <alt-photo-process-l@usask.ca>
Sent: Friday, February 22, 2008 4:19 PM
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