U of S | Mailing List Archive | alt-photo-process-l | RE: Ferric Oxalate or Ferric Ammonium Oxalate

RE: Ferric Oxalate or Ferric Ammonium Oxalate

Hi Eric,

I haven't done prints with FO other than few Kallitype tests so I can't
share personal experience w/ it as a sensitizer for Pt/Pd salts but I'm
quite sure that my prints don't exhibit any haze and/or highlight
fogging and/or low contrast. Probably yours is a paper/clearing and/or
negative DR problem - my usual coating mix gives me 29 steps in the
31-step tablet for instance (in other words my usual negative DR is log

I'm currently using the same AFO sensitizer that I mixed about 10 months
ago and it still works well without any fogging and/or speed change or
other negative effect. IME AFO is quite stable even when in solution -
you can almost think that it keeps indefinitely "especially when
compared to FO".


-----Original Message-----
From: Eric Neilsen [mailto:ejnphoto@sbcglobal.net] 
Sent: 03 Kasım 2006 Cuma 02:27
To: alt-photo-process-l@usask.ca
Subject: RE: Ferric Oxalate or Ferric Ammonium Oxalate

Sandy, Yes the AFO is indeed a much better defined chemical than the FO,
which can vary all over the place. POP pt/pd prints can most certainly
be made. One thing that I seemed to see in prints made from negs that
print well with FO when using AFO, are prints that look a little hazy.
That might be OK, if you were making prints of foggy or moody scenes but
for crisp images, not so hot. It may also be a paper pH issue, where
what works for FO will react differently for AFO prints. It does have a
shelf life after mixing but last at least as long as FO if not twice as