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

RE: Ferric Oxalate or Ferric Ammonium Oxalate

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.
> Sandy
> 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.
>>>  Loris,
>>>  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?
>>>  Sandy
>>>  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".
>>>>>   Regards,
>>>>>   Loris.