Re: Vandyke Question
Another thing I mentioned last time was that sometimes "distilled water"
isn't... I had some checked at our chem lab & what was sold as distilled
was regular tap water.
J.
On Fri, 22 Feb 2008, Christina Z. Anderson wrote:
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
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