In the bleaching step it appears that atmospheric oxygen is somehow involved. I had a piece of paper sitting in a H202/CA bleach mixture, with part of it out in free air (though it had been coated with a small amount of the bleach). I was surprised to find that the submerged part had barely bleached at all by the time the part in open air was white.
I wonder if there's much "overhead" on paper. What I mean is, in some places there may be more AgBr than is necessary to reach black... if that's true ( I have no idea if it is ) then in your example it might be possible to bring out a little more detail with additional 2nd exposure. With H2O2 I don't think there could be any advantage that way... extra re-exposure will just add tone to the highlights, not bring out detail better than with dichromate. At least that's my guess!
you guys are blowing my mind
Yes absolutely - but only if you add enough CA. I've observed the same thing. If you stick a strip of black developed and washed paper in and let it sit, it will quickly form a pure white strip along the waterline where air is available while the part in the liquid will stay black. If you take it out and let it sit on your desk, it will turn white when it dries as air becomes available. This only happens if there is a large amount of CA. It will bleach a very little at first because there's a little dissolved air, but it will get used up and then proceed only as fast as air is introduced ( faster if agitated ). By the way, this proves that the silver is not dissolved in the liquid but is left on the paper in a "white" form... the one sitting on your desk had the liquid evaporate and no liquid to carry off the silver which is still there. The white silver "salt" that remains is quite light sensitive, but it's not rehalogenated ( or at least it doesn't redevelop into the original image ).
The process Joe and Don and Himself have been using uses less CA and high concentration of H2O2 and is driven more by the the decomposition of the H2O2. I think one of the reasons we're having inconsistent results is that it's a mixture of these two different reactions, and the amount of light sensitivity depends on how much of each reaction takes place. But for sure, if you use a consistent amount of CA:H2O2 and process consistently you get repeatable results with the same amount of light sensitivity each time.
I checked the MSDS for the paper developer I used (Adox neutol eco) - apparently it contains EDTA. That would explain the bleaching.
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