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

RE: Ferric Oxalate or Ferric Ammonium Oxalate

OK, I will mix up the ammonium tetrachloropalladate this evening and have it on hand tomorrow when the FO you sending arrives. Sure are hopeful this will work. I am about to go up the wall trying to figure out why this all went so far south on me.

Thanks again for the FO and advice. I will let you know how it goes.


At 1:35 PM -0600 11/3/06, wcharmon@wt.net wrote:
The short answer is yes. You can use developer with FAO/AmPd. Particularly
when the ambient humidity is below 35%, you need developer to get a solid
image. As I may have mentioned, I have not used Na2 as a contrast control
agent for this process, and I am uncertain how the oxidizers used in DOP
affect FAO/POP prints. My instinctive, from the gut, hunch is that they
should behave similarly since the same redox reaction is occuring.

The one thing of which I am certain is that humidity control will be
essential to produce consistent results. I got some of the most beautiful
straight pd prints using the Ware chemistry, but found that changing the
humidity from 35% to 45% had a huge effect not only on print color, but
also contrast. I have some plexiglass in my garage that is ready to glue
up into a sealed up humidification box so I can investigate this approach.

In any case, I really like the combination of traditional FO and AmPd
using my usual techniques. I don't think you can go wrong mixing up some
ammonium tetrachloropalladate even if you decide not to pursue the full
Ware approach.


 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
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
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".