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Anyone tried kodak e6 patent(US5948604)?

Rudeofus

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As you probably know, E-6 FD is one of the best B&W developers out there, that's why Kodak formulated it this way. Ron told me, that unlike HQ the oxidation product of HQMS doesn't have developer properties, and this causes HQMS to give better sharpness than HQ.

The only issue with E-6 FD is, that it is a very very powerful developer, which would develop your B&W film to normal contrast within less than a minute. The way to handle this is dilution: E-6 FD working solution diluted 1+9 makes a very decent B&W developer. I typically use it at 26°C for 10-12 minutes, and this gives me at least normally developed negatives. I like the development at 26°C, since at summer time not even my cold water always comes out colder than that.

Since I have - I believe - already mentioned this at least once, you can consider this a formula in the public domain :-D
 

Raghu Kuvempunagar

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It seemed too simple to be true. Thanks for sharing your experience and perspectives.

Since I have - I believe - already mentioned this at least once, you can consider this a formula in the public domain :-D

 

River Mantis

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Hey. Nice to see you here. I used the information from these two patents. What I came to is redissolving the sulfonation product (it's almost solid at room temperature) in the 4x excess of sulphuric acid (in the described disilfonate synthesis process it's present from the beginning) at around 50º C and neutralising with stoichiometric amount of KOH in the form of 50% solution (yes, that's sketchy). After cooling to about 30º C the precipitate formed. Just filter it and wash with isopropyl alcohol. Got 47% this way, still not sure if I got any disulfonate contamination. And there is a hope that with the excess of acid (and some amount of water) sulfate just won't precipitate, as bisulfate is very soluble.
 

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River Mantis

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CZA is the easiest here to synthesize. The method from 1893 (!) paper works surprisingly well, except that I kept the temperature at 135º because there is a clue in some later paper that above 150º the CZA (amide) may not form at all. Got about 20% this way
 

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River Mantis

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BTW do you remember the exact book?
 

River Mantis

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As for potassium sulfate contamination, you can determine the amount by simply precipitating the sulfate with calcium chloride.
 

River Mantis

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Here are few samples what I got from Velvia 100 using homebrew HQMS-K and CZA. Everything else is as in the patent except the order of preparation of buffer solutions, the absence of any chelating agents and some occasional base substitutions like K<->Na. And there are no accelerators in the color developer. I'm going to try ethylenediamine but it's still on the way. The images are clearly underdeveloped, so I'm going to do some troubleshooting.
 

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czygeorge

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Hi Mantis
This patented product has been produced in my country and has been used to develop tens of thousands of rolls of reversal film.
We also used Fujifilm e6 control strips,shows diviation within ± 0.02D.

But because we produce according to this patent without modification at all (and we have a professional laboratory), we use the purest chemical raw materials, and use chemical analysis for testing, so the quality of the output is very good
But you may not have this condition, so you can consider buying the e6 chemical that Kodak is about to re produce.Or because you may need to use substitutes for many of the ingredients or the purity is insufficient, so you must also check the pH of the chemical
 

River Mantis

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Do you mean specifically the year 1999 patent mentioned in topic? Because it seems like at some point (according to 1993 patent) Kodak's first developer had slightly more developing agents and lower pH. I also checked Fuji patent and it asks for a double amount of Dimezone-S.
 

Child Ship

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Yes, they have been producing the E-6 chemical kit with this patented formula for over a year now, and it's exceptionally high-quality.
 
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czygeorge

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Yes the 1999 one is the only correct one(or the only one our lab has proved it is totally correct)
Here are the pH data of its working solution if it can help you
FD:9.81
RV:5.2-5.5
CD:12.05
PBL:6-7
BL:5.3-5.6