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

RE: Ferric Oxalate or Ferric Ammonium Oxalate

Clay, did you use the ammonium tetrachloropalladate with DOP printing with FAO or FO?. And how did you control contrast? I would really be more interested in using FAO with DOP than POP since visually evaluating density would be hard to do with a vaccum frame. So if the FAO works with ammonium tetrachloropalladate developing in potassium oxalate, and I can use dichromate contrast control in the developer, that would be a perfect solution for me.


At 12:35 PM -0600 11/3/06, wcharmon@wt.net wrote:

Yes, that is all you need to make the Ware formulations. You will notice
that his metal salt concentrations are slightly higher than is typically
used in DOP. I have used the ammonium tetrachloropalladate for DOP
printing as well. I think it has a visually deeper Dmax and a more neutral
tone than the sodium salt version.



 I have Palladium II Chloride powder on hand.
 Looking at Mike Ware's directions, it appears
 that I can  prepare Ammonium
 Tetrachloropalladate(II) by mising ammonium
 chloride with palladum II chrloride.  Would this
 be all I need, along with the FAO, to give Ware's
 POP method a try?  In other words, can a basic
 sensitizer be made with just  Ammonium
 Tetrachloropalladate(II) and Ammonium Ferric
 Oxalate, or do I need something else?

 Also Is it possible to control contrast with the
 Ware method  with dichromate? I would rather do
 this than attempt to do so by varying RH?


 At 9:01 AM +0200 11/3/06, Loris Medici wrote:
Hi Kerik,

Main salt: Li2PdCl4.
Metal additives (for color control - sometimes): K2PtCl4 and KAuCl4.
Non-metal additives: NaOW and Amm.Di. (for contrast and color control).


P.S. Your "reply-to" address is not empty, so I had to write the group's
address manually.

-----Original Message-----
From: Kerik [mailto:kerik@kerik.com]
Sent: 03 Kas×m 2006 Cuma 08:24
To: alt-photo-process-l@usask.ca
Subject: RE: Ferric Oxalate or Ferric Ammonium Oxalate


Which metal salts are you using with AFO?


  -----Original Message-----
  From: Loris Medici [mailto:mail@loris.medici.name]
  Sent: Thursday, November 02, 2006 10:10 PM
  To: alt-photo-process-l@usask.ca
  Subject: 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 2.9!).

  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".