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 > 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: >>Sandy, >> >>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. >> >>Clay >> >>> >>> 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). >>>> >>>>Regards, >>>>Loris. >>>> >>>>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 Kasžm 2006 Cuma 08:24 >>>>To: alt-photo-process-l@usask.ca >>>>Subject: RE: Ferric Oxalate or Ferric Ammonium Oxalate >>>> >>>> >>>>Loris, >>>> >>>>Which metal salts are you using with AFO? >>>> >>>>Thanks, >>>>Kerik >>>> >>>>> -----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. >>> >
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