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. Sandy 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. ClayClay, 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. ClayLoris, 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.caSubject: 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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