Dug said:
This longevity issue with Borax developers is something I have not heard of before. I have been using sodium citrate developer (like Steve and Sandy) but am interested in the Borax-based developers.
I checked out Dick Steven's Kallitype book from the library yesterday to satisfy my curiousity of his "exhaustive" treatment of the Kallitype process. Yep - it's all in there *EXCEPT* mention of sodium citrate during his developer parade. Every permutation and combination of other developers and especially Borax-based developers are discussed.
The literature - "Keepers of Light" and other historical process books never discuss longevity in terms of developer. They discuss the historical confusion over fixing times/processes.
Two questions - Is using Borax developers a really bad idea or just an unknown that needs to be explored further? Is experimenting with the ratio of Ferric Oxalate to Silver Nitrate a fruitful exercise (pursuant to the experiments in Dick Steven's book)?
Thanks!
Doug
My objection to borax developers is that the pH is quite high, certainly more than pH 7.0, and in that condition you can get the formation of iron hydroxide. If this stain forms it is very difficult to remove from the paper, even with very strong clearing agents. And if the stain remains in the paper, it will almost surely over time react with the silver.
I am not specifically aware of what Mike Ware has said about borax developers for silver iron processes, but if he questions their longetivity I am sure his reasons are sound.
BTW, I don't believe Dick Stevens mentions using either potassium oxalate or ammonium citrate as a developer for kallitype. But they both also work very well with kallitype, as they do with Pt./Pd. General thinking today is that since kallitype is so similar to Pt./Pd. the same materials should work well with either process. That has been my experience, especially with papers and with the importance of low pH developers. I am guessing that most of Steven's research was done well before much of what is considered today better practice for Pt./Pd. was known, and is therefore based mostly on historical literature, most of which dates from the first two or three decades of the 20the century since kallitype was not widely practiced from about 1945 to the rebirth of alternative processes in the late 1970s.
Sandy