Photo Engineer
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Charon was the proposed use of H2 and F2 as fuels for a new rocket with high specific impulse. The reaction is the highest energy chemical reaction possible, but would have contaminated the east coast from Georgia to Cuba.
Fortunately, an astute engineer pointed this out to NASA. One of their oversights I guess.
PE
Kodak found that early PPD developers were affected by the acid used to make the salt, and converted to either the Sulfate or the p-Tosyl salt which you see in use today. This is true to the present time in CD-6 and CD-3 for example. The chloride had varying adverse effects on early Cl/Br emulsions used in print films and papers. I don't know what all was affected, as the change was complete when I joined EK.
PE
My military manuals from the 50s do not describe any developer such as the one above nor does any Kodak manual. They basically describe Metol + HQ developers with 50 g/l or so of Sodium Sulfate, and that is the reason I asked the question.
PE
Just some thoughts on all of this recent activity. Mainly, who is going to "prove" efficacy of any old formula and who is going to point out which is most correct?
PE
Coincidentally, just a few hours ago I did a Metol version again, but somewhat differently. This time I did not bother to try to separate out the Metol base from the sulfate. I used KOH instead of NaOH. I haven't got my good K sulfite, so used Na. I put 41.5 grams of metol in about 750 ml water. I added 100 grams of Na2SO3 and added KOH until everything dissolved. The sulfate resulting from the neutralizing of thr H2SO4 is still in there. The solution is an amber color which is hardly seen in the measuring syringe. It appears that diluted 1+50 it is about a 10 minute developer for EDU 400 Ultra. Needless to say I have no idea how long it will last as stock, but the color of what I have is much different from what I had then. When I get a negative that I'm willing to show as a picture, I'll post it.Patrick, Ian;
In an earlier post, someone commented that the Metol version of Rodinal that Patrick had brought up some time back does not appear to have long shelf life.
This has been bothering me for 2 reasons. Metol is a very close relative to pAP. It should keep better as it is a less powerful reducing agent IIRC or less strong base in any event. Also, its properties with Sulfite are quite different than HQ and more like pAP. So, if it keeps poorly something else is going on here that might give clues to Rodinal.
Any thoughts?
PE
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